Search

To investigate the influence of maternal Se supply and plane of nutrition on lamb morbidity, mortality, and passive transfer of IgG, pregnant ewe lambs were used in 2 experiments with 2 x 3 factorial treatment arrangements. Supplementation of Se began at breeding and was either adequate Se (ASe, 9.5 µg/kg of BW) or high Se (HSe, 81.8 µg/kg of BW) in Exp. 1 or ASe (11.5 µg/kg of BW) or HSe (77.0 µg/kg of BW) in Exp. 2. On d 50 or 40 of gestation for Exp. 1 or 2, respectively, ewes were assigned randomly to 1 of 3 nutritional planes: 60% (RES), 100% (CON), or 140% (HIGH) of NRC requirements. This resulted in the following treatments: ASe-RES; ASe-CON; ASe-HIGH; HSe-RES; HSe-CON; and HSe-HIGH. Upon parturition, lambs were separated from their dams and serum samples obtained. Lambs were fed artificial colostrum for the first 20 h and then placed on milk replacer and grain pellets until completion of the study (Exp. 1, 57 d; Exp. 2, 21 d). Twenty-four hours after parturition, lamb serum samples were collected for IgG analysis. All lambs were reared similarly and morbidity and mortality assessed. Main effects were considered significant when P = 0.05. In Exp. 1, there was a Se x plane of nutrition interaction (P = 0.01) for lamb morbidity from birth to weaning and for 24-h IgG concentration. Lambs from ASe-RES and HSe-HIGH ewes were treated more frequently (P < 0.01) for respiratory and gastrointestinal disease, and lambs from HSe-HIGH ewes had the lowest (P < 0.01) 24-h serum IgG concentration. In Exp. 1, lambs from HIGH ewes also had the greatest (P < 0.01) mortality rates from birth to weaning compared to lambs from CON and RES ewes. In Exp. 2, there was an effect (P < 0.01) of maternal plane of nutrition with lambs from RES ewes having increased 24-h IgG compared to lambs from CON and HIGH ewes. There was no effect of maternal Se supplementation on lamb 24-h IgG in Exp. 2; however, there was a Se x plane of nutrition interaction (P < 0.01) for morbidity. From birth to 21 d of age, lambs from ASe-CON ewes had reduced (P < 0.01) treatment days compared to lambs from any of the other treatment groups. There also tended (P = 0.08) to be an effect of maternal Se supplementation on lamb mortality with increased mortality observed in lambs from HSe ewes. Results from the studies show a restricted maternal plane of nutrition can increase lamb serum IgG. Selenium results were not consistent between the two experiments and may be due to differences in maternal Se. [ABSTRACT FROM AUTHOR]

Malnutritional stress during gestation is a well-established driver of metabolic disfunction in offspring. Extended exposure to malnutrition requires metabolic plasticity as the animal shifts toward a catabolic state. In this paper we demonstrate the influence of malnutrition throughout gestation on uterine artery hemodynamics and the metabolism of the dam and neonate. We hypothesized that gestational malnutrition reduces blood flow of the maternal uterine artery and regulates the metabolic profile of the dam and offspring. Further, the combination of these factors consequently influences the concentration of metabolites in the cerebrospinal fluid of the neonate at birth. To test our hypotheses, pregnant cows caring a single female fetus were assigned to treatments by age and body condition score to one of three individually-fed dietary treatments: Underfed, Control, or Overfed throughout gestation. Uterine blood flow was measured via transrectal Doppler ultrasonography in late gestation. Blood samples were collected from dams throughout gestation, and blood and cerebrospinal fluid were collected from neonates at birth to analyze concentration of metabolites. In the current report, we reveal that maternal malnutrition regulates uterine artery hemodynamics and the maternal metabolic profile throughout gestation. This is the first report to demonstrate that maternal undernutrition leads to an increase in the concentration of urea nitrogen in neonates. Finally, a concentration gradient of metabolites from the dam to neonatal cerebrospinal fluid was observed, which may have potential implications for central nervous system development. These findings not only illustrate the complexity of the maternal-to-fetal interaction required to support the growth of the fetus and homeostasis of the dam but also reveals a novel avenue for investigating the influence of protracted maternal malnutrition on metabolic pathway preferences in offspring. Moreover, these findings are of paramount importance in the development of intervention strategies for morbid neonates. [ABSTRACT FROM AUTHOR]

This study aims to determine the impact of different GDF9 genotypes on feed intake, nutrient digestibility, and nitrogen balance in Kacang goats by examining various metabolic processes. Twenty-nine Kacang goats were genotyped using PCR-RFLP DNA at position g.3855A/C of the GDF9 gene in exon 2. A 2 x 2 factorial design with two factors, namely, diet type (diets 1 and 2) and genotype (homozygote AA and heterozygote AC), was adopted. Diet 1 group comprised 11 goats with the AA genotype and 4 goats with the AC genotype, and the diet 2 group consisted of 9 goats with the AA genotype and 5 goats with the AC genotype. Both diets had the same protein content (isoprotein) and consisted of free-choice Napier grass (Pennisetum purpureum). Diet 1 had an additional 400 g of concentrate containing 11.25% crude protein (CP) and 55.86% total digestible nutrients (TDN). Diet 2 was a total mixed ration (TMR) containing 12.46% crude protein and 67.92% TDN. Results demonstrated a significant interaction (p<0.05) effect between diet and genotype on crude protein (CP) digestibility, neutral detergent fiber (NDF) digestibility, fecal nitrogen (N feces), urinary nitrogen (N urine), nitrogen retention (%), and blood urea nitrogen (BUN). However, no significant interaction effect was observed on the consumption of dry matter (DM), CP, crude fiber (CF), nitrogen free extract (NFE), and NDF and the digestibility of DM, CF, and NFE. TMR resulted in a 9% higher consumption of NDF, higher nutrient digestibility, improved nitrogen balance, average daily gain (ADG), and elevated glucose levels compared with diet 1. Kacang goats with the AC genotype exhibited better CP digestibility and increased nitrogen intake than those with the AA genotype. In conclusion, the GDF9 genotype influences the nutrient digestibility in Kacang goats, and those with the AC genotype utilize feed nutrients more efficiently than those with the AA genotype. The AC genotype resulting from the GDF9 gene mutation at position g.3855A>C can be used for genomic marker selection of high-quality Kacang goats in nutrient digestibility. [ABSTRACT FROM AUTHOR]

Proper establishment of the placenta is important for fetal survival; however, placental adaptations to inadequate maternal nutrition or other stressors are imperative for fetal growth to be optimal. The effects of maternal nutritional status and activity level on placental vascular function and uteroplacental blood flows are important to understand as improper placental function leads to reduced growth of the fetus. In environments where fetal growth can be compromised, potential therapeutics may augment placental function and delivery of nutrients to improve offspring performance during postnatal life. Factors that could enhance placental function include supplementation of specific nutrients, such as protein, hormone supplements, such as indolamines, and increased activity levels of the dam. To understand the mechanism of how the maternal environment can impact uterine or umbilical blood flows, assessment of placental vascular reactivity has been studied in several large animal models. As we begin to understand how the maternal environment impacts uterine and umbilical blood flows and other uteroplacental hemodynamic parameters, development of management methods and therapeutics for proper fetal growth can be achieved. [ABSTRACT FROM AUTHOR]

To examine the effects of nutrient restriction during midgestation to late gestation on maternal and fetal digestive enzyme activities, 41 singleton ewes (48.3 ± 0.6 kg of BW) were randomly assigned to dietary treatments: 100% (control; CON; n = 20) or 60% of nutrient requirements (restricted; RES; n = 21) from day 50 until day 90 (midgestation). At day 90, 14 ewes (CON, n = 7; RES, n = 7) were euthanized. The remaining ewes were subjected to treatments of nutrient restriction or remained on a control diet from day 90 until day 130 (late gestation): CON-CON (n = 6), CON-RES (n = 7), RES-CON (n = 7), and RES-RES (n = 7) and were euthanized on day 130. The fetal and maternal pancreas and small intestines were weighed, subsampled, and assayed for digestive enzyme activity. One unit (U) of enzyme activity is equal to 1 µmol of product produced per minute for amylase, glucoamylase, lactase, and trypsin and 0.5 µmol of product produced per minute for maltase and isomaltase. Nutrient restriction during midgestation and late gestation decreased (P < 0.05) maternal pancreatic and small intestinal mass but did not affect fetal pancreatic or small intestinal mass. Maternal nutrient restriction during late gestation decreased (P = 0.03) fetal pancreatic trypsin content (U/pancreas) and tended to decrease (P < 0.08) fetal pancreatic trypsin concentration (U/g), specific activity (U/g protein), and content relative to BW (U/kg of BW). Nutrient restriction of gestating ewes decreased the total content of α-amylase (P = 0.04) and tended to decrease total content of trypsin (P = 0.06) and protein (P = 0.06) in the maternal pancreas on day 90. Nutrient restriction during midgestation on day 90 and during late gestation on day 130 decreased (P = 0.04) maternal pancreatic α-amylase-specific activity. Sucrase activity was undetected in the fetal and maternal small intestine. Nutrient restriction during late gestation increased (P = 0.01) maternal small intestinal maltase and lactase concentration and tended to increase (P = 0.06) isomaltase concentration. Realimentation during late gestation after nutrient restriction during midgestation increased lactase concentration (P = 0.04) and specific activity (P = 0.05) in the fetal small intestine. Fetal small intestinal maltase, isomaltase, and glucoamylase did not respond to maternal nutrient restriction. These data indicate that some maternal and fetal digestive enzyme activities may change in response to maternal nutrient restriction. [ABSTRACT FROM AUTHOR]

Poor maternal nutrition, both restricted-feeding and overfeeding, during gestation can negatively affect offspring growth, body composition, and metabolism. The effects are observed as early as the prenatal period and often persist through postnatal growth and adulthood. There is evidence of multigenerational effects demonstrating the long-term negative impacts on livestock production. We and others have demonstrated that poor maternal nutrition impairs muscle growth, increases adipose tissue, and negatively affects liver function. In addition to altered growth, changes in key metabolic factors, increased glucose concentrations, insulin insensitivity, and hyperleptinemia are observed during the postnatal period. Furthermore, there is recent evidence of altered metabolism in specific tissues (e.g. muscle, adipose, and liver) and stem cells. The systemic and local changes in metabolism demonstrate the importance of determining the mechanism(s) by which maternal diet programs offspring growth and metabolism in an effort to develop novel management practices to improve the efficiency of growth and health in these offspring. [ABSTRACT FROM AUTHOR]

Dried distiller grains with solubles (DDGS) are a popular byproduct used in the livestock feed industry as it is a cost-effective feedstuff that is rich in crude protein and minerals. However, a common concern related to the use of DDGS in livestock diets is the negative impact that affects animal dry matter intake (DMI) and growth. To further investigate this challenge, the experiments aimed to evaluate the effect of feeding 1) two different diets, control versus heat processed DDGS or 2) increasing the concentration of DDGS and its effect on body weight (BW), average daily gain (ADG), DMI, and gain to feed ratio (G:F) in finishing lambs. In experiment 1, both diets were the same except for the heat processing of DDGS; the control diet used a commercial DDGS source directly from the supplier and the processed diet contained the same commercial DDGS source that differed through additional heat processing. For DDGS heat processing, 40% moisture was added to the DDGS and heated at 150 °C for 70 min. After the heating process, the DDGS was placed in a second oven at 56 °C for 2 d to allow for humidity evaporation. Lambs (n  = 34), blocked by sex and BW, were housed in pens (2 to 3 lambs/pen, 6 pens/treatment) and were fed for 42 d. Lamb DMI was measured daily, and BW was measured every 14 d. In experiment 2, lambs (n = 75) were blocked by BW (5 lambs/ pen, 5 pens/treatment) and fed diets differing in inclusion rates of DDGS (10%, 20%, and 30%). The feeding period lasted for 56 d, and lamb DMI and BW were measured daily or every 28 d, respectively. In both experiments, diets were isonitrogenous, and the feeding procedure utilized slick bunk management. Data were analyzed in SAS using a mixed model considering the treatments as fixed effects and pen and block as random effects. In experiment 1, there were no treatment differences (P  ≥ 0.13) in ADG, DMI, and G:F in finishing lambs. In experiment 2, a linear and quadratic contrast were used to separate the mean and demonstrated that increasing the concentration of DDGS decreased lamb DMI (linear P  < 0.01; quadratic P  = 0.05), but did not affect lamb BW, ADG, or G:F (P  ≥ 0.26). Despite that previous research shows differences in animal growth because of an increase in DDGS concentration, our experiments illustrated that heat processing or increased concentrations of DDGS up to 30% in finishing lamb diets are not responsible for a decrease in lamb performance. [ABSTRACT FROM AUTHOR]

The objective of this study was to analyze the effects of immunological suppression of ovarian function and estrus (Improvest®; Zoetis Inc.) on carcass cutting yields and meat quality. A total of 1,080 gilts were allocated by weight and assigned to pens of 27 pigs/pen. Pens were then randomly selected to be managed with or without immunological suppression of ovarian function and estrus (IMP vs. CON). Improvest was administered to each IMP gilt on days 7 and 67 of the study. Pigs were marketed on day 89 (n  = 8 heaviest gilts per pen), 103 (n  = 8 next heaviest gilts per pen), and 117 (remaining pigs/pen) of the study. The heaviest 47 to 50 carcasses for each treatment from each marketing group were selected for carcass cutting tests and evaluation of meat quality the day following slaughter (approximately 32-h postmortem). A smaller subset of 18 to 20 pork loins per treatment from each marketing group were selected for meat quality evaluation following 14 d of postmortem storage. Carcasses were fabricated according to institutional meat purchase specifications (IMPS) and meat quality analyses included pH and instrumental color at 32-h postmortem and purge loss, pH, instrumental color, intramuscular fat (IMF), cooking loss, and star probe following 14 d of postmortem storage. Live performance data were analyzed using the pen as the experimental unit, while carcass data were analyzed using the individual carcass as the experimental unit. During the post-second dose period (measured from days 70 to 85), IMP gilts consumed 10.8% more feed (P  < 0.01) and grew 13.5% faster (P  < 0.01) compared with CON gilts. Hot carcass weight (HCW), and the weights of many cuts, were significantly influenced by the interaction of Improvest management and marketing group. Therefore, the focus was directed toward primal weights and merchandized cut weights when expressed as a percentage of HCW. When expressed as a percentage of HCW, primal-cut yield and merchandized-cut yield calculations were not different (P  = 0.33 and P  = 0.65, respectively) between CON and IMP gilts. Meat quality traits did not differ (P  > 0.05) between CON and IMP gilts, with the exception of instrumental a* at 32-h postmortem which was 0.32 units greater for CON gilts compared with IMP gilts. In summary, managing market gilts with immunological suppression of ovarian function and estrus improves the rate of weight gain through increased feed intake; however, carcass-cutting yields were not significantly changed. [ABSTRACT FROM AUTHOR]

Poor maternal nutrition of F0 ewes impairs F1 offspring growth, with minimal differences in glucose tolerance or select metabolic circulating factors, and independent of differences in residual feed intake (RFI). To determine if poor maternal nutrition in F0 ewes alters F2 offspring growth, circulating leptin, feed efficiency, or glucose tolerance, F0 ewes (n  = 46) pregnant with twins were fed 100% (control), 60% (restricted), or 140% (over) of National Research Council requirements from days 30 ± 0.02 of gestation until parturition. At 16 to 19 mo of age, female F1 (n  = 36) offspring were bred to generate F2 offspring [CON-F2 (n  = 12 ewes; 6 rams), RES-F2 (n  = 7 ewes; 13 rams), or OVER-F2 (n  = 13 ewes; 9 rams) corresponding to diets of the granddam (F0)]. Lamb body weights (BW) and blood samples were collected weekly from days 0 to 28 and every 14 d until day 252 of age. Circulating leptin was measured in serum at days 0, 7, 14, 56, 210, and 252. An intravenous glucose tolerance test was performed at days 133 ± 0.28. At days 167 ± 0.33, individual daily intake was recorded over a 77-d feeding period to determine RFI. Rams were euthanized at days 285 ± 0.93, and body morphometrics, loin eye area (LEA), back fat thickness, and organ weights were collected and bone mineral density (BMD) and length were determined in the right hind leg. During gestation, OVER-F1 ewes tended to be 8.6% smaller than CON-F1 ewes (P  ≤ 0.06). F2 offspring were of similar BW from birth to day 70 (P  ≥ 0.20). However, from days 84 to 252, RES-F2 offspring tended to be 7.3% smaller than CON-F2 (P  ≤ 0.10). Granddam diet did not influence F2 ram body morphometrics, organ or muscle weights, LEA, adipose deposition, or leg BMD (P  ≥ 0.84). RES-F2 (−0.20) and CON-F2 (−0.45) rams tended to be more feed efficient than CON-F2 ewes (0.31; P  ≤ 0.08). No effects of granddam diet were observed on glucose or insulin average or baseline concentrations, area under the curve, first-phase response, or ratio (P  ≥ 0.52). However, CON-F2 rams (297 mg/dL ± 16.5) had a greater glucose peak compared with RES-F2 rams (239 mg/dL ± 11.2; P  = 0.05). Peak insulin concentrations were not influenced by granddam diet (P  = 0.75). At d 56, RES-F2 and OVER-F2 offspring had 53.5% and 61.8% less leptin compared with CON-F2 offspring, respectively (P  ≤ 0.02). These data indicate that poor maternal nutrition impacts offspring growth into the second generation with minimal impacts on offspring RFI, glucose tolerance, and circulating leptin. [ABSTRACT FROM AUTHOR]

Despite rigorous vaccination protocols, calf morbidity is the primary contributor to economic loss in the calf sector of the dairy industry. Melatonin has modulated immune response in other mature animal species. We hypothesized that exogenous melatonin may improve the cellular response to vaccination in dairy calves. Our objective was to evaluate the effect of exogenous melatonin on polymorphonuclear leukocyte (PMN) function in Holstein heifer calves during immunization. Sixty neonatal Holstein heifers were enrolled by birth cohort (block) and randomized to one of four treatments: control (CON), vaccination of 0.5 mg ovalbumin on days 0 and 21 (VAC) , implantation of 24 mg melatonin on day 0 (MEL), or both melatonin and vaccine treatments (MVAC). Jugular blood was collected on days 0, 21, 42, and 63 to measure circulating melatonin, anti-ovalbumin immunoglobulin-G, and PMN function. Calves implanted with melatonin had greater circulating melatonin than non-implanted on day 21 (P  < 0.01). Anti-ovalbumin IgG was greater for vaccinated than non-vaccinated calves (P  < 0.01). Anti-ovalbumin IgG was greater for MVAC than VAC calves on day 63. Percent of cells and mean florescence intensity of cells performing oxidative burst decreased from day 0 to day 63 (P  < 0.01) but were not affected by treatment (P ≥  0.26). There was a tendency (P  = 0.10) for an interaction of melatonin, vaccination, and day for the mean florescence intensity of cells performing phagocytosis where MVAC was greater than all other treatments on d 42. Exogenous melatonin may alter PMN function of calves during vaccination. Further research is needed to define the effect of melatonin on development of antigen-specific IgG during programmed vaccination protocols. [ABSTRACT FROM AUTHOR]

The objective was to determine the effects of net energy (NE) during the grow-finish period on live performance and carcass characteristics of market gilts managed with immunological suppression of ovarian function and estrus (Improvest®; IMP) compared with market gilts not managed with Improvest (CON). The 104-d study began when 1,008 gilts (11 wk old; average starting weight of 30.8 kg) were allocated by weight to 48 pens with 21 gilts/pen. Half of the pens were randomly selected to be managed with Improvest while the other half of the pens were not managed with Improvest. Three dietary programs differing in their NE were formulated over five dietary phases (according to standardized ileal digestible lysine requirements) to provide an average of 2,218 kcal/kg (low NE), 2,343 kcal/kg (medium NE), or 2,468 kcal/kg (high NE). The experiment was designed as a 2 × 3 factorial with main effects of Improvest management and NE. For the overall study period, there were no significant interactions (P  ≥ 0.20) for average daily feed intake (ADFI), average daily gain (ADG), or Gain:Feed (G:F). There were also no significant interactions between Improvest management and NE (P  ≥ 0.30) for carcass characteristics. However, IMP gilts consumed more feed (6.8% greater ADFI; P  < 0.01), grew faster (5.0% greater ADG; P  < 0.01), were less efficient (1.8% lower G:F; P  < 0.01), heavier (3.5 kg hot carcass weight; P  < 0.01), and fatter (1.9 mm greater backfat thickness and 1.26% less predicted lean carcass yield; P  < 0.01). No difference (P  = 0.21) in carcass dressing percentage between IMP and CON gilts was reported. For the overall study period, gilts fed low NE and medium NE diets consumed more feed compared with gilts fed high NE diets (6.8% more ADFI for low NE and 5.7% more for medium NE; P  < 0.01), and gilts fed low NE diets grew 2.5% slower (P  < 0.01) than gilts fed medium NE diets, while gilts fed high NE diets were intermediate and not different from the other NE treatments. This resulted in gilts fed Low NE diets being the least efficient (3.8% lower G:F than medium NE and 7.1% lower G:F than High NE; P  < 0.01). Overall, these data indicate that typical Improvest response levels were sustained at each of the NE treatments evaluated in this study as there were no significant interactions for Improvest management and NE; however, consideration should still be provided to the known production impacts of low NE diets. [ABSTRACT FROM AUTHOR]

The objective was to evaluate the effects of Improvest on the performance and carcass characteristics of gilts from two different genetic sire lines and the performance of Improvest gilts with castrated male pigs. It was hypothesized that performance parameters observed for Improvest gilts would be similar to barrows, thus narrowing the performance gaps between traditionally managed gilts and barrows. Pigs were from Large White/Landrace dams and either Duroc–Pietrain (DP) or Duroc (D) sires. Females within each genetic sire line were randomized by weight to receive the first dose of Improvest (IMP) on day 25 of the study or to serve as a nontreated control (DP IMP gilt (n  = 6 pens; 19 pigs/pen), D IMP gilt (n  = 6 pens; 19 pigs/pen), DP CON gilt (n  = 6 pens; 19 pigs/pen), D CON gilt (n  = 6 pens; 19 pigs/pen). The second dose of Improvest was administered 6 wk later (i.e. day 67). Barrows did not receive Improvest (DP barrow [ n  = 10 pens; 19 to 20 pigs/pen], D barrow [ n  = 10 pens; 19 to 20 pigs/pen]). Average daily gain (ADG), average daily feed intake (ADFI), and gain-to-feed ratio (G:F) were measured at 21 d intervals throughout the duration of the study. The targeted weight for pigs to be marketed was 133 ± 2.5 kg. Carcass characteristics and loin quality parameters were evaluated on a subset of pigs (n  = 283). Improvest-treated gilts of both genetic lines had increased (P  ≤ 0.05) ADG and ADFI compared to untreated gilts during the post-second dose intervals with values exceeding that of barrows from day 84 to marketing. Overall, DP IMP gilts had increased (P  ≤ 0.05) G:F post-second dose compared to DP CON gilts and DP barrows, yet all other treatments were similar. As pigs were marketed at a similar weight, there was no difference in the final weight, however, DP IMP gilts and DP barrows reached market weight sooner (P  ≤ 0.05) than DP CON gilts (109.9 and 111.8 vs. 114.3 ± 0.8 d). Backfat and loin weight were greater (P  < 0.01) in IMP gilts versus CON gilts, while IMP gilts and barrows had similar values within each respective genetic sire line. There were no differences between treatments (P  ≥ 0.08) for pH and instrumental color of the loins. When the pass rate of loins (Japanese color score ≥ 3.0 and marbling ≥ 2.0) was evaluated, IMP gilts were at intermediate values between CON gilts and barrows for each respective genetic sire line. Overall, Improvest within a genetic line improved gilt carcass measurements so that they were more similar to barrows. [ABSTRACT FROM AUTHOR]

The neuroendocrine hormone melatonin is associated with circadian rhythms and has antioxidant and vasodilative properties. In cattle, melatonin rescues fetal growth during maternal nutrient restriction in a seasonally dependent manner, but melatonin research in swine is limited. The objective of this study was to evaluate the effects of dietary melatonin supplementation during mid to late gestation on circadian rhythm and muscle growth and development of the longissimus dorsi in utero and postnatally. Sows received 20 mg of dietary melatonin daily (MEL) or no melatonin supplement (CON). Experiment 1 supplemented sows from gestational age (dGA) 38 ± 1 to 99 ± 1, experiment 2 supplemented sows from 41 to 106 ± 1 dGA, and experiment 3 supplemented sows from 60 dGA to farrowing. At harvest, morphometric measurements of all fetuses were taken, while the small (SM), medium (MED), and large (LG) piglets from each litter were used for further analysis. Prenatal data were analyzed using the MIXED procedure of SAS, and postnatal data were analyzed using the GLIMMIX procedure. Fetal morphometrics were analyzed for fixed the effect of treatment, and transcript abundance was analyzed for treatment, time, and size. Postnatal parameters were analyzed for fixed effects of treatment, size, and production stage. In experiment 1, MEL increased (P  = 0.016) Period 1 (PER1) transcript abundance in the evening (PM) compared to the morning (AM). In experiment 1, myogenin (MYOG) transcript abundance was increased (P  = 0.033) in MEL fetuses in the AM compared to MEL in the PM. Myogenic factor 5 (MYF5) and paired box 7 (PAX7) were increased (P  = 0.016) in the PM. Fetuses from MEL-treated sows had increased (P  < 0.05) BW, curve crown-rump length, and head circumference in experiment 2. In experiment 2, MEL increased (P  = 0.012) PER1 and Period 2 (PER2) transcript abundance in the PM. In experiment 2, myoblast differentiation 1 (MYOD) was increased (P  = 0.016) in SM and MED fetuses, while MYF5 and PAX7 were increased (P  = 0.019) in SM fetuses. Postnatal BW was increased (P  = 0.025) in MED and LG MEL-treated offspring compared to CON. Insulin-like growth factor 1 (IGF1) was downregulated (P  = 0.050) in MEL-treated offspring, while insulin-like growth factor 1 receptor (IGF1R) was upregulated (P  = 0.009) in MEL offspring. These results indicate that maternal melatonin supplementation during gestation modulates fetal circadian regulatory genes and alters myogenic genes during growth. [ABSTRACT FROM AUTHOR]

The mechanistic target of rapamycin (mTOR) predominantly regulates the expression and activity of placental nutrient transporters. The mTOR pathway can be activated by several nutrients, including the essential amino acid methionine. Additionally, previous research in nonruminant animals suggests that mTOR is influenced in a sexually dimorphic manner. In bovine, there is limited understanding of how maternal nutrition and offspring sexual dimorphism affect the placental transfer of nutrients. Thus, we investigated the effects of increasing the supply of dietary methionine to beef cattle heifers during mid-gestation on mTOR signaling, placental nutrient transporters, and fetal growth in male and female offspring. Forty purebred Angus heifers were used in a randomized complete block design experiment. From days 90 to 180 of gestation, heifers received a basal diet with no added methionine (CON , n  = 20), or the basal diet plus 8.3 g of rumen-protected methionine (MET , n  = 20) per animal daily. All animals received a basal diet in the first and third trimesters of gestation. Cotyledonary tissue samples were collected at parturition and utilized to examine the mTOR pathway and nutrient transporters through protein and gene expression analysis. The offspring's body weight was measured at birth. Data were analyzed using a mixed model that included the fixed effect of treatment, offspring sex, their interactions, and the random effect of block. At day 170 of gestation, MET-supplemented heifers showed higher plasma concentrations of methionine and glutamate (P  < 0.01) and lower glycine and proline levels (P  ≤ 0.01) compared to the CON group. A treatment × sex interaction was observed for calf birth weight (P  = 0.03). In heifers that delivered male calves, MET supplementation increased the birth weight of the calves (P  < 0.01). However, the dietary treatments had no effect on the birth weight of female calves (P  = 0.32). The increase in birth weight of male calves from MET-fed heifers resembles the upregulation of placental mTOR and phosphorylated mTOR (P  ≤ 0.03), as well as the amino acid transporters SLC1A5 , SLC7A5 , SLC38A6, and SLC38A11, and the glucose transporters SLC2A1 and SLC2A8 (P ≤  0.05). Our findings suggest that increasing the supply of methionine to beef heifers during mid-gestation can modulate placental nutrient transport and fetal growth in a sex-dependent manner and that these effects are mediated, at least in part, by the mTOR pathway. [ABSTRACT FROM AUTHOR]

Rambouillet rams were managed on either a positive (POS ; gain 12% body weight [ BW ]; n  = 8), maintenance (MAINT ; maintain BW; n  = 8), or negative (NEG ; lose 12% BW; n  = 8) plane of nutrition before breeding. Rams were bred to ewes (n  = 10 per ram) that were managed similarly throughout gestation, and lambs were fed a common diet postnatally. Two ewe lambs (7.6 ± 0.02 mo of age, BW = 47.1 ± 1.17 kg) from each sire were selected and within-pair, randomly assigned to be managed for a moderate (MOD , 0.11 kg/d; n  = 23) or accelerated (ACC , 0.20 kg/d; n = 22) rate of gain for 56 d. Ewe lamb BW was recorded on a weekly basis and blood was collected on days 0, 28, and 56 for analysis of insulin-like growth factor 1 (IGF-1), triiodothyronine (T 3 ), thyroxine (T 4 ), glucose, blood urea nitrogen (BUN), and non-esterified fatty acids (NEFA). Intravenous glucose tolerance tests (IVGTT) were conducted from days −7 to −4 and days 57 to 64. A unilateral ovariectomy was performed and ovarian follicles were staged and counted macro and microscopically. Sire treatment × day and ewe treatment × day interactions were present for BW (P  ≤ 0.05), where POS had slower growth than MAINT and NEG, and tended (P  = 0.10) to have reduced average daily gain (ADG) when managed at an accelerated rate of gain. By design, ACC had greater BW and ADG than MOD (P  < 0.05). Concentrations of IGF-1 and T4 were greater in ACC than MOD (P  ≤ 0.05), and NEG tended to have greater concentrations of IGF-1 than POS and MAINT (P  = 0.08). At the first IVGTT, the concentration of insulin was influenced by a sire treatment × time interaction (P  ≤ 0.05), suggesting impaired secretion in NEG-sires ewes, but no differences in area under the curve (AUC) for glucose, insulin, or their ratio (P  ≥ 0.11). No interactive effects of sire and ewe treatment (P  ≥ 0.52) were observed at the second IVGTT, but insulin and insulin:glucose ratio were influenced by sire treatment × time (P  ≤ 0.02), as NEG had greater insulin concentration at 60 min than MAINT (P  = 0.03) and greater AUC than POS and MAINT (P  ≤ 0.04). No differences in ovary size, weight, or total counts of macro and microscopic follicles were observed (P  ≥ 0.23). Ewes-fed ACC had a greater number of small surface follicles (P  = 0.02), whereas MOD tended to have a greater number of large surface follicles and tertiary follicles (P  < 0.06). These findings suggest that the paternal plane of nutrition influences female offspring physiology, particularly at varying growth rates. [ABSTRACT FROM AUTHOR]

Seminal plasma uterine priming is important for pregnancy and offspring phenotype in mice and swine; however, impacts on the uterus of the dam and her offspring in cattle are unknown. We sought to determine the effects of seminal plasma uterine priming at estrus on uterine transcriptomics, early gestation (days 35, 40, and 45) embryo morphometrics, mid- to late-gestation (days 140 to 220) uterine artery hemodynamics, birth morphometrics, and liver transcriptomics in offspring at 30 d of age. Multiparous Angus-based commercial beef cows were randomly assigned to receive treatment at estrus: 0.5 mL pooled seminal plasma in the uterine body (n  = 31, seminal plasma primed) or no treatment (n  = 31, control). Seven days later a subset of cows (n  = 4/treatment) underwent uterine biopsies, and the remaining cows underwent embryo transfer. Embryo crown-rump length and uterine artery hemodynamics were measured during gestation using ultrasonography. Morphometrics of the calf were collected within 24 h of parturition. Liver biopsies were collected at 30 d of age. Data were analyzed by analysis of variance (ANOVA) in a completely randomized design for the effect of treatment. Myosin heavy chain I (JSP.1) was downregulated [Benjamin–Hochberg adj P (BH) ≤ 0.05] and ABO alpha 1-3-N-acetylgalactosaminyltransferase and alpha 1-3-galactosyltransferase (ABO) was upregulated (BH adj P ≤ 0.05) in the uterus of seminal plasma primed cows 7 d after treatment. Embryo crown-rump length was less (P  < 0.05) in seminal plasma primed cows. Mid- to late-gestation (days 140 to 220) uterine artery resistance was increased (P  < 0.05) in seminal plasma primed cows. Seminal plasma priming did not alter birth weights or curve-crown-rump length, but heart girth was increased (P  < 0.05) in offspring from seminal plasma primed cows. There were no differentially expressed genes (BH adj P ≤ 0.05) in offspring liver at 30 d of age; however, myosin light chain, phosphorylatable, fast skeletal muscle (MYLPF) was absent in all liver samples from calves from seminal plasma primed cows. In contrast, vomeronasal 1 receptor bosTauV1R414 (BOSTAUV1R414) was present in 6 of the 7 liver samples from calves from seminal plasma primed cows. Seminal plasma uterine priming alters uterine transcriptomics, negatively impacts early gestation embryo growth, and mid- to late-gestation uterine artery resistance suggesting downstream vascular anomalies. However, these in utero conditions did not impact offspring from birth to 30 d of age. [ABSTRACT FROM AUTHOR]

With global warming, there are growing challenges for raising taurine and composite beef cattle populations in tropical regions, including elevated temperatures, limited forage availability, parasite infestation, and infectious diseases. These environmental factors can trigger specific physiological responses in the developing fetus, which may have long-term implications on its performance. Therefore, the main objective of this study was to assess the influence of naturally induced thermal stress during the gestation period on the subsequent performance of tropical composite beef cattle progeny. Furthermore, we aimed to investigate the impact of genotype-by-gestational thermal environment interaction (G×Eg) on traits under selection pressure in the breeding population. A total of 157,414 animals from 58 farms located in various Brazilian states were recorded for birth weight (BW), preweaning weight gain (PWG), yearling weight (YW), hip height (HH), scrotal circumference (SC), and days to first calving (DFC). We first applied a linear regression model to the BW data, which revealed that the last 40 d of gestation were suitable for calculating the mean temperature humidity index (THIg). Subsequent regression analyses revealed that for every 10-unit increase in THIg, detrimental effects of approximately 1.13% to 16.34% are expected for all traits evaluated. Genetic parameters were estimated through a reaction norm model using THIg as the environmental descriptor. The posterior means of heritability estimates (SD) were 0.35 (0.07), 0.25 (0.03), 0.31 (0.03), 0.37 (0.01), 0.29 (0.07), and 0.20 (0.09) for the direct effect of BW, PWG, YW, HH, SC, and DFC, respectively. These estimates varied along the range of THIg values, suggesting a variable response to selection depending on the thermal environment during gestation. Genetic correlation estimates between more divergent THIg values were low or negative for YW, PWG, and DFC, indicating that the best-performing individuals at low THIg values may not perform as well at high THIg values and vice versa. Overall, thermal stress during gestation impacts the future performance of beef cattle offspring. Our results indicate the need for developing effective breeding strategies that take into account G×Eg effects and the re-ranking of breeding animals along the THIg scale, particularly for traits such as DFC that are highly sensitive to thermal stress. [ABSTRACT FROM AUTHOR]

Consumption of toxic endophyte-infected tall fescue (EI) results in poor reproductive performance in domestic livestock. In this study, the objective was to evaluate the effects of ergovaline exposure during mid-gestation (days 93 through 188 of gestation) on dam performance, the growing female fetus, and the subsequent growth and reproductive performance of the gestationally exposed heifer calves. Pregnant Angus and Simmental-Angus cows were blocked by age (2 to 3, to 7, and >7 y), body weight (BW), and breed; and then randomly assigned to graze either novel endophyte-infected tall fescue (EN ; <5% infection rate; n  = 27 year 1, n  = 16 year 2) or toxic EI (99% infection rate; n  = 27 year 1, n  = 17 year 2). Weekly BW, body condition scores (BCS), hair coat scores, hair shedding scores (HSS), and blood samples for progesterone (P4) analysis were collected from mid-April through July of 2017 (year 1) and 2018 (year 2). Gestation length, birth weight, placental characteristics, heifer calf growth, onset of puberty, ovarian characteristics, and artificial insemination pregnancy rates were measured. Data were analyzed using the MIXED procedure of SAS. Cows grazing EI pastures had reduced average daily gain, reduced BCS, greater HSS, and decreased P4 concentrations compared to cows on EN pasture (P  < 0.01). Birth weights were decreased for heifers whose dams were exposed to EI pastures during their second trimester (P  < 0.01). Heifer pregnancy rates were not impacted by EI pasture exposure during gestation for either year of the study. However, a treatment-by-year effect was seen for the pregnancy rate for EI-exposed heifers in year 2; EI-exposed heifers in year 2 had increased pregnancy rates at two of the inseminations. Combined, these data reinforce that consumption of toxic EI during gestation can negatively impact both dam and offspring performance. More studies are needed to evaluate more parameters in an effort to elucidate the possible life-long impacts of ergovaline exposure during gestation. [ABSTRACT FROM AUTHOR]

One-carbon metabolites (OCM) are metabolites and cofactors which include folate, vitamin B12, methionine, and choline that support methylation reactions. The objectives of this study were to investigate the effects of moderate changes in maternal body weight gain in combination with OCM supplementation during the first 63 d of gestation in beef cattle on (1) B12 and folate concentrations in maternal serum (2) folate cycle intermediates in maternal and fetal liver, allantoic fluid (ALF), and amniotic fluid (AMF) and (3) metabolites involved in one-carbon metabolism and related metabolic pathways in maternal and fetal liver. Heifers were either intake restricted (RES) and fed to lose 0.23 kg/d, or fed to gain 0.60 kg/d (CON). Supplemented (+ OCM) heifers were given B12 and folate injections weekly and fed rumen-protected methionine and choline daily, while non-supplemented (-OCM) heifers were given weekly saline injections. These two treatments were combined in a 2 × 2 factorial arrangement resulting in 4 treatments: CON-OCM, CON + OCM, RES-OCM, and RES + OCM. Samples of maternal serum, maternal and fetal liver, ALF, and AMF were collected at slaughter on day 63 of gestation. Restricted maternal nutrition most notably increased (./  ≤ 0.05) the concentration of vitamin B12 in maternal serum, 5,10-methylenetetrahydrofolate and 5,10-methenyltetrahydrofolate in maternal liver, and cystathionine in the fetal liver; conversely, maternal restriction decreased (P  = 0.05) 5,10-methylenetetrahydrofolate concentration in fetal liver. Supplementing OCM increased (P  ≤ 0.05) the concentrations of maternal serum B12, folate, and folate intermediates, ALF and AMF 5-methyltetrahydrofolate concentration, and altered (P  ≤ 0.02) other maternal liver intermediates including S-adenosylmethionine, dimethylglycine, cystathionine Glutathione reduced, glutathione oxidized, taurine, serine, sarcosine, and pyridoxine. These data demonstrate that OCM supplementation was effective at increasing maternal OCM status. Furthermore, these data are similar to previously published literature where restricted maternal nutrition also affected maternal OCM status. Altering OCM status in both the dam and fetus could impact fetal developmental outcomes and production efficiencies. Lastly, these data demonstrate that fetal metabolite abundance is highly regulated, although the changes required to maintain homeostasis may program altered metabolism postnatally. [ABSTRACT FROM AUTHOR]

Endometrial-derived uterine histotroph is a critical component of nutrient supply to a growing conceptus throughout gestation; however, the effect of nutritional plane on histotroph nutrient composition remains unknown in multiparous cows. We hypothesized that differing planes of nutrition would alter histotroph and serum nutrient composition in beef cattle. Thus, we evaluated serum and histotroph amino acid and glucose composition, and serum non-esterified fatty acids (NEFA) and blood urea nitrogen (BUN) in cows individually fed to maintain body weight (BW; 0 kd/d, n  = 9; CON) compared with those losing moderate BW (−0.7 kg/d, n  = 9; NEG). After 49 d of differing nutritional planes, cows were subjected to the 7-d CoSynch + controlled internal drug release device estrus synchronization protocol and then slaughtered on day 62. Blood serum (days 0 and 62) and uterine histotroph [day 62; from uterine horns ipsilateral and contralateral to the corpus luteum (CL)] were collected and analyzed for concentrations of amino acids, glucose, and NEFA. Performance characteristics, body composition via ultrasound (days 0 and 62), and carcass characteristics were collected. Body condition score, change in BW, average daily gain, dry matter intake, and gain:feed were decreased (P  ≤ 0.05) in NEG vs. CON cows. There were no differences in body composition or carcass characteristics, except an increase (P  ≤ 0.05) in dressing percentage in NEG cows due to differences in gut fill, consistent with study design. Serum NEFA increased (P  ≤ 0.05) in the NEG group, but there were no differences between NEG vs. CON in glucose or BUN. Serum histidine increased (P  ≤ 0.05) and alanine, isoleucine, and tryptophan decreased (P  ≤ 0.05) in NEG vs. CON cows. Compared with that of the uterine horn ipsilateral to the CL, histotroph from the uterine horn contralateral to the CL had increased (P  ≤ 0.05) isoleucine, asparagine, and proline concentrations in NEG cows, and decreased (P  ≤ 0.05) tryptophan as a proportion of essential and total amino acids. There were no differences in glucose concentrations of histotroph contralateral or ipsilateral to the CL. Cow nutritional plane does alter serum and histotroph amino acid composition, although the presence of an embryo may be necessary to fully elucidate these changes. Differences in serum and histotroph tryptophan should be given consideration in future studies due to its importance as an essential amino acid in protein synthesis and bioactive affects. [ABSTRACT FROM AUTHOR]

Our study objectives were to evaluate the effects of divergent rates of body weight (BW) gain during early gestation in beef heifers on F0 performance, metabolic and endocrine status, colostrum immunoglobulins, and subsequent F1 calf characteristics, growth performance, concentrations of hormones and metabolites, and response to vaccination. Angus-based heifers (n  = 100; BW = 369 ± 2.5 kg) were adapted to individual feeding for 14 d and bred using artificial insemination with female-sexed semen. Heifers were ranked by BW and assigned to either a basal diet targeting 0.28 kg/d gain (low [ LG ], n  = 50) or the basal diet plus an energy/protein supplement targeting 0.79 kg/d gain (moderate gain [ MG ], n  = 50) until day 84 of gestation. Dam BW and blood samples were collected at 6 time points during gestation; body composition was evaluated on days −10 and 84; and fetal measurements were taken on days 42, 63, and 84. At calving (LG, n  = 23; MG, n  = 23), dam and calf BW were recorded; and colostrum, calf body measurements, and blood samples were collected. Cow–calf pairs were managed on a common diet from calving to weaning, followed by a common postnatal development period for all F1 female offspring. Growth performance, hormone and metabolite profiles, feeding behavior, and reproductive performance were assessed from birth to prebreeding in F1 heifers. Offspring were vaccinated against respiratory disease and bovine viral diarrhea pathogens on days 62.3 ± 4.13 and 220.3 ± 4.13 postcalving. By design, MG dams were heavier (P  < 0.0001) than LG on day 84, and the BW advantage persisted until subsequent weaning of F1 calves. Concentrations of serum IGF-1 and glucose were increased throughout gestation (P  < 0.001) in MG dams, whereas concentrations of NEFA were decreased (P  < 0.001) in LG dams. Calves from MG dams were 2.14 kg heavier (P  = 0.03) and had larger chest circumference (P  = 0.04) at birth compared with LG cohorts. Heifers from MG dams continued to have greater (P  ≤ 0.03) BW gain and feed efficiency during the development period, but no differences were observed (P  ≥ 0.13) in body composition, concentrations of hormones and metabolites, feeding behavior, puberty attainment, and response to vaccination in F1 offspring. Hence, early gestation rate of gain impacted BW and concentrations of glucose and IGF-1 throughout gestation in the F0 dam, resulting in altered F1 calf BW and measurements at birth and increased gain and efficiency during the development period. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the dose-dependent response of one-carbon metabolite (OCM : methionine, choline, folate, and vitamin B12) supplementation on heifer dry matter intake on fixed gain, organ mass, hematology, cytokine concentration, pancreatic and jejunal enzyme activity, and muscle hydrogen peroxide production. Angus heifers (n  = 30; body weight [ BW ] = 392.6 ± 12.6 kg) were individually fed and assigned to one of five treatments: 0XNEG : total mixed ration (TMR) and saline injections at days 0 and 7 of the estrous cycle, 0XPOS : TMR, rumen-protected methionine (MET) fed at 0.08% of the diet dry matter, rumen-protected choline (CHOL) fed at 60 g/d, and saline injections at days 0 and 7, 0.5X : TMR, MET, CHOL, 5-mg B12, and 80-mg folate injections at days 0 and 7, 1X : TMR, MET CHOL, 10-mg vitamin B12, and 160-mg folate at days 0 and 7, and 2X : TMR, MET, CHOL, 20-mg vitamin B12, and 320-mg folate at days 0 and 7. All heifers were estrus synchronized but not bred, and blood samples were collected on days 0, 7, and at slaughter (day 14) during which tissues were collected. By design, heifer ADG did not differ (P  = 0.96). Spleen weight and uterine weight were affected cubically (P  = 0.03) decreasing from 0XPOS to 0.5X. Ovarian weight decreased linearly (P  < 0.01) with increasing folate and B12 injection. Hemoglobin and hematocrit percentage were decreased (P  < 0.01) in the 0.5X treatment compared with all other treatments. Plasma glucose, histotroph protein, and pancreatic α-amylase were decreased (P  ≤ 0.04) in the 0.5X treatment. Heifers on the 2X treatment had greater pancreatic α-amylase compared with 0XNEG and 0.5X treatment. Interleukin-6 in plasma tended (P  = 0.08) to be greater in the 0XPOS heifers compared with all other treatments. Lastly, 0XPOS-treated heifers had reduced (P  ≤ 0.07) hydrogen peroxide production in muscle compared with 0XNEG heifers. These data imply that while certain doses of OCM do not improve whole animal physiology, OCM supplementation doses that disrupt one-carbon metabolism, such as that of the 0.5X treatment, can induce a negative systemic response that results in negative effects in both the dam and the conceptus during early gestation. Therefore, it is necessary to simultaneously establish an optimal OCM dose that increases circulating concentrations for use by the dam and the conceptus, while avoiding potential negative side effects of a disruptive OCM, to evaluate the long-term impacts of OCM supplementation of offspring programming. [ABSTRACT FROM AUTHOR]

Fall-calving primiparous beef females [body weight (BW): 451 ± 28 (SD) kg; body condition score (BCS): 5.4 ± 0.7] were individually-fed either 100% (control; CON; n  = 13) or 70% (nutrient restricted; NR; n  = 13) of metabolizable energy and metabolizable protein requirements for maintenance, pregnancy, and growth from day 160 of gestation to parturition. Doppler ultrasonography of both uterine arteries was conducted pre-treatment and every 21 d from days 181 to 265 of gestation. Expelled placentas were collected, and ipsilateral cotyledonary tissue was sampled to assess relative messenger ribonucleic acid (mRNA) expression. Placentas were separated into ipsilateral and contralateral sides, dissected (cotyledonary vs. intercotyledonary), and dried. Data were analyzed with nutritional plane, treatment initiation date, and calf sex (when P  < 0.25) as fixed effects. Uterine blood flow included day and nutritional plane × day as repeated measures. We previously reported that post-calving, NR dams weighed 64 kg less and were 2.0 BCS lower than CON, but calf birth weight was not affected. Maternal heart rate was less (P  < 0.001) for NR dams than CON after nutritional planes began. Nutritional plane did not affect (P  ≥ 0.20) uterine artery hemodynamics, but all variables were affected (P  ≤ 0.04) by day. Contralateral cotyledonary and placental weight were less (P  ≤ 0.04) and contralateral intercotyledonary weight and number of cotyledons tended to be less (P  ≤ 0.10) for NR dams than CON, but ipsilateral and whole placental weights were not affected (P  ≥ 0.13). Ipsilateral placental weight as a percentage of total placental weight was greater (P  = 0.03) for NR dams than CON. Whole placental cotyledonary: intercotyledonary weight was less (P  = 0.01) for NR dams than CON. Placental efficiency was not affected (P  = 0.89) by nutritional plane. Cotyledonary relative mRNA expression of GLUT3 and SNAT2 was greater (P  ≤ 0.05) and relative expression of GLUT1, GLUT4, and NOS3 tended to be greater (P  ≤ 0.07) for NR dams than CON. Nutritional plane did not affect (P  ≥ 0.13) relative mRNA expression of GLUT5, 4F2hc, CAT1, LAT1, LAT2, VEGFA, FLT1, KDR, GUCY1B3, and PAG2. Despite less contralateral placental growth, beef heifers experiencing late gestational nutrient restriction maintained uterine artery blood flow and total placental mass and had 4 nutrient transporters and 1 angiogenic factor upregulated in cotyledons, all of which likely contributed to conserving fetal growth. [ABSTRACT FROM AUTHOR]

To examine the effects of feeding a vitamin and mineral supplement to beef heifers throughout gestation on mineral status and hormone/endocrine profiles in the dam and calf, and morphometric characteristics and organ mass of the calf at 30 h after birth, Angus-based heifers (n  = 72, 14 to 15 mo of age, initial body weight [ BW ] = 380.4 ± 50.56 kg) were estrus synchronized and artificially inseminated (AI) with female-sexed semen. Heifers were blocked by BW and randomly assigned to receive either a basal diet (CON; n  = 36) or a basal diet plus a vitamin and mineral supplement (VTM ; n  = 36) via an individual feeding system beginning at breeding, with both diets targeting BW gains of 0.45 kg heifer−1·d−1. Heifers not pregnant after the first AI (CON, n  = 19; VTM, n  = 18) were rebred via AI 60 d after treatment initiation, and heifers gestating female fetuses (CON, n  = 7; VTM, n  = 7) received treatments throughout gestation and were experimental units for this study. Calves were separated from their dams and fed colostrum replacer within 2 h of birth and euthanized 30 h after the first feeding. Calf morphometrics were recorded, and tissues were weighed and sampled. Serum from the dam at calving and serum, liver, and muscle from the calf at 30 h were analyzed for concentrations of minerals. Serum from the dam and calf were analyzed for concentrations of leptin, vitamins A, D, and E, cortisol, growth hormone, and insulin-like growth factor 1. All response variables were analyzed using the MIXED procedure of SAS. Calf body morphometrics and BW of the dam at calving (P  ≥ 0.32), calf organ weights (P  ≥ 0.21), and calf ovarian follicle counts (P  ≥ 0.13) were not affected by maternal treatment. Concentrations of Se and Co in calf serum and Se in calf liver were increased (P  ≤ 0.02) in VTM. Serum concentrations of Co and vitamin A in the dam were greater (P  ≤ 0.01) in supplemented compared with nonsupplemented dams, and serum concentrations of vitamin D were greater (P  ≤ 0.0003) in supplemented dams and calves compared with the nonsupplemented cohort. Maternal supplementation supported vitamin and mineral status in the neonate, yet had no discernable impact on BW, organ mass, or circulating hormones/metabolites in the calf. Evaluating offspring at later postnatal time points is warranted to determine if prenatal vitamin and mineral supplementation affects performance, health, metabolism, and efficiency of energy utilization in key metabolic tissues in the calf. [ABSTRACT FROM AUTHOR]

This study evaluated if vasoactive intestinal polypeptide (VIP) influences growth performance, nutrient digestibility, nitrogen balance, and digestive enzyme activity. Sixteen weather lambs (69.6 ± 1.9 kg) were housed in individual pens, adapted to a corn grain-based diet, and randomly assigned to 2 treatment groups. Lambs were injected intraperitoneally every other day for 28 d with saline (0.9% NaCl) containing no VIP (n  = 8; control) or containing VIP (n  = 8; 1.3 nmol/kg body weight [ BW ]). All lambs were transferred to individual metabolic crates for the final 7 d of the experiment to measure nitrogen balance and nutrient digestibility. At the end of the treatment period, lambs were slaughtered, and pancreatic tissue, small intestinal tissue, and rumen fluid were collected for protein, digestive enzymes, ruminal pH, and volatile fatty acid (VFA) analyses. Lambs treated with VIP had greater final BW, average daily gain, and gain:feed (P  = 0.01, 0.05, 0.03, respectively). No differences between treatment groups were observed (P  ≥ 0.25) for nutrient intake, digestibility, nitrogen retention, ruminal pH, and VFA concentrations. Moreover, VIP treatment did not influence (P  ≥ 0.19) plasma glucose, urea N, and insulin concentrations. Treatment with VIP increased (P  = 0.03) relative cecum weight (g/kg BW) and decreased (P  = 0.05) relative brain weight. Pancreatic and intestinal digestive enzyme activities, except for duodenal maltase (P  = 0.02), were not influenced (P  ≥ 0.09) by VIP treatment. These data suggest that the administration of VIP may have potential to improve average daily gain and gain:feed in lambs fed grain-based diets. [ABSTRACT FROM AUTHOR]

Fall-calving primiparous beef females [body weight (BW): 451 ± 28 (SD) kg; body condition score (BCS): 5.4 ± 0.7] were individually-fed 100% (control; CON; n  = 13) or 70% (nutrient restricted; NR; n  = 13) of estimated metabolizable energy and metabolizable protein requirements from day 160 of gestation to calving. Post-calving, all dams were individually-fed tall fescue hay supplemented to meet estimated nutrient requirements for maintenance, growth, and lactation until day 149 of lactation. Four-hour milk yields were collected on days 21, 42, 63, 84, 105, and 147 of lactation, and milk nutrient composition was determined. Doppler ultrasonography of both pudendoepigastric arterial trunks was conducted every 21 d from days 24 to 108 of lactation. Total mammary blood flow was calculated, and hemodynamics from both sides were averaged. Data were analyzed as repeated measures with nutritional plane, day of lactation, their interaction, calving date, and calf sex (if P  < 0.25) as fixed effects. We previously reported that post-calving, NR dams weighed 64 kg less and were 2.0 BCS lower than CON, but calf birth weight was not affected. Milk weight and volume were 15% less (P  = 0.04) for NR dams than CON. Milk protein concentration was lower (P  = 0.008) for NR dams than CON, but triglyceride and lactose concentrations were not affected (P  ≥ 0.20) by nutritional plane. Milk urea N concentration of NR dams tended to be greater (P  = 0.07) on day 42 but was lower (P  = 0.01) on day 147 of lactation than CON. Total milk protein, triglyceride, and lactose yields were less (P  ≤ 0.05) for NR dams than CON. Total milk urea N yield was less (P  ≤ 0.03) for NR dams than CON on days 21, 63, and 147 of lactation. Maternal heart rate was greater (P  = 0.008), but pudendoepigastric arterial trunk peak systolic velocity, resistance index, and cross-sectional area were less (P  ≤ 0.04) and pulsatility index tended to be less (P  = 0.06) for NR dams than CON. Mammary blood flow was 19% less (P  = 0.004) for NR dams than CON, but mammary blood flow relative to milk weight or dam BW was not affected (P  ≥ 0.14) by nutritional plane. Most milk yield, milk nutrient composition, and mammary blood flow variables were affected (P  ≤ 0.04) by day of lactation. In summary, first-parity beef females that were nutrient restricted during late gestation and then fed to meet estimated nutrient requirements during lactation had decreased milk nutrient yield and a similar reduction in mammary blood flow. [ABSTRACT FROM AUTHOR]

We hypothesized that restricted maternal nutrition and supplementation of one-carbon metabolites (OCM; methionine, folate, choline, and vitamin B12) would affect placental vascular development during early pregnancy. A total of 43 cows were bred, and 32 heifers successfully became pregnant with female calves, leading to the formation of four treatment groups: CON − OCM (n  = 8), CON + OCM (n  = 7), RES − OCM (n  = 9), and RES + OCM (n  = 8). The experimental design was a 2 × 2 factorial, with main factors of dietary intake affecting average daily gain: control (CON; 0.6 kg/d ADG) and restricted (RES; −0.23 kg/d ADG); and OCM supplementation (+OCM) in which the heifers were supplemented with rumen-protected methionine (7.4 g/d) and choline (44.4 g/d) and received weekly injections of 320 mg of folate and 20 mg of vitamin B12, or received no supplementation (−OCM; corn carrier and saline injections). Heifers were individually fed and randomly assigned to treatment at breeding (day 0). Placentomes were collected on day 63 of gestation (0.225 of gestation). Fluorescent staining with CD31 and CD34 combined with image analysis was used to determine the vascularity of the placenta. Images were analyzed for capillary area density (CAD) and capillary number density (CND). Areas evaluated included fetal placental cotyledon (COT), maternal placental caruncle (CAR), whole placentome (CAR + COT), intercotyledonary fetal membranes (ICOT, or chorioallantois), intercaruncular endometrium (ICAR), and endometrial glands (EG). Data were analyzed with the GLM procedure of SAS, with heifer as the experimental unit and significance at P  ≤ 0.05 and a tendency at P  > 0.05 and P  < 0.10. Though no gain × OCM interactions existed (P  ≥ 0.10), OCM supplementation increased (P  = 0.01) CAD of EG, whereas nutrient restriction tended (P  < 0.10) to increase CAD of ICOT and CND of COT. Additionally, there was a gain × OCM interaction (P  < 0.05) for CAD within the placentome and ICAR, such that RES reduced and supplementation of RES with OCM restored CAD. These results indicate that maternal rate of gain and OCM supplementation affected placental vascularization (capillary area and number density), which could affect placental function and thus the efficiency of nutrient transfer to the fetus during early gestation. [ABSTRACT FROM AUTHOR]

Fall-calving primiparous beef females [body weight (BW): 451 ± 28 (SD) kg; body condition score (BCS): 5.4 ± 0.7] were individually-fed 100% (control; CON; n  = 13) or 70% (nutrient restricted; NR; n  = 13) of estimated metabolizable energy and metabolizable protein requirements from day 160 of gestation to calving. Post-calving, all dams were individually-fed tall fescue hay supplemented to meet estimated nutrient requirements for maintenance, growth, and lactation in Calan gates until day 149 of lactation, which limited calves to milk only. From day 150 of lactation until weaning at day 243, dams and calves were group-fed in drylots. Dam BW and metabolic status were determined every 21 d, and BCS and backfat (BF) were determined every 42 d of lactation until weaning. Pre-weaning calf BW, size, and metabolic status were determined every 21 d. Data were analyzed with nutritional plane, calving date, and calf sex (when P  < 0.25) as fixed effects. Circulating metabolites included day and nutritional plane × day as repeated measures. We previously reported that post-calving, NR dams were 64 kg and 2.0 BCS less than CON, but calf BW and size at birth were not affected. During the first 147 d of lactation, NR dams gained more (P  < 0.01) BW than CON and increased (P  < 0.01) BCS, while CON decreased (P  ≤ 0.01) BCS and BF. Previously, NR dams had lower (P  < 0.01) circulating triglycerides on day 1 of lactation, tended to have lower (P  = 0.08) triglycerides on day 21, and had lower (P  ≤ 0.04) non-esterified fatty acids (NEFA) on days 21 and 243 than CON. Maternal glucose and urea N were not affected (P  ≥ 0.73). At weaning, NR dams weighed 17 kg less (P  = 0.15), were 0.67 BCS lower (P  < 0.01), and tended to have less (P  = 0.06) BF. Calves born to NR dams weighed less (P  = 0.02) than CON by day 42 of age and were 13% smaller (P  < 0.01) at weaning. Calf girth measures diverged (P  ≤ 0.05) by day 21 of age, and skeletal size measures were less (P  ≤ 0.08) for calves born to NR dams at most timepoints after day 63 of age. Calves born to NR dams tended to have lower (P  = 0.09) circulating urea N pre-weaning than CON, but glucose, triglycerides, and NEFA were not affected (P  ≥ 0.16). In summary, first-parity beef females that were nutrient restricted during late gestation experienced compensatory growth and gained body condition during lactation but were still thinner at weaning. Nutrient restriction reduced pre-weaning calf growth, likely due to decreased milk production. [ABSTRACT FROM AUTHOR]

We evaluated the effects of feeding a vitamin and mineral supplement to nulliparous beef heifers throughout gestation on the mineral status of the dam, calf, placenta, and colostrum; offspring growth performance; and physiological responses of offspring raised as replacement heifers. Angus-based heifers (n  = 31, initial body weight [BW] = 412.5 ± 53.68 kg) were adapted to an individual feeding system for 14 d, estrus synchronized and bred with female-sexed semen. Heifers were ranked by BW and randomly assigned to receive either a basal diet (CON ; n  = 14) or the basal diet plus 113 g heifer−1 d−1 of the vitamin and mineral supplement (VTM ; n  = 17). Targeted BW gains for both treatments was 0.45 kg heifer−1 d−1. Liver biopsies were obtained from dams at breeding, days 84 and 180 of gestation. At calving, liver biopsies were taken from dams and calves; colostrum, placenta, and blood samples were collected; and calf body measurements were recorded. After calving, all cow-calf pairs received a common diet through weaning, and F1 heifer calves were managed similarly after weaning. Offspring growth performance, feeding behavior, blood metabolites, and hormones were evaluated from birth through 15 mo of age. Data were analyzed using the MIXED procedure in SAS with repeated measures where appropriate. Hepatic concentrations of Se decreased in VTM dams (P  ≤ 0.05) from day 84 to calving, while concentrations of Cu decreased in VTM and CON (P  ≤ 0.05) from day 84 to calving. Calf liver concentrations of Se, Cu, Zn, and Co at birth were greater for VTM than CON (P  ≤ 0.05), but calf birth BW and body measurements were not different (P  = 0.45). Placental Se, colostrum quantity, total Se, Cu, Zn, and Mn in colostrum were greater (P  ≤ 0.04) in VTM dams than CON. Finally, offspring from VTM dams were heavier than CON (P  < 0.0001) from weaning through 15 mo of age. These results were coupled with greater (P  ≤ 0.04) blood glucose at birth, decreased (P  ≤ 0.05) blood urea nitrogen at pasture turn out and weaning, and altered feeding behaviors in VTM offspring compared with CON. Maternal gestational vitamin and mineral supplementation enhanced mineral status in dams and F1 progeny, augmented postnatal offspring growth and blood metabolites. Consequently, in utero vitamin and mineral supplementation may exert programming outcomes on the performance and productivity of females raised as herd replacements and should be considered when developing diets for gestating cows and heifers. [ABSTRACT FROM AUTHOR]

The objective of the current study was to examine the effects of supplemental melatonin implants on uterine artery blood flow from mid to late gestation in beef cattle and subsequent development of their male offspring. Commercial beef heifers (n = 32) and cows (n = 25) were bred via artificial insemination and assigned to 1 of 2 groups supplemented with melatonin implants (MEL) or without (CON) at day 180, 210, and 240 of gestation. Uterine artery blood flow was determined using color Doppler ultrasonography. A subset of 12 crossbred heifers (n = 6 MEL; n = 6 CON) underwent Cesarean sections on day 243 ± 2 of gestation to allow for placentome collection. Maternal and fetal serum were collected to analyze melatonin concentrations. The remaining cattle were allowed to calve and at weaning (195 ± 2 d of age), bull calves (n = 15) were castrated and testicular tissue harvested for seminiferous tubule analysis. Heifer uterine artery blood flow was increased (P = 0.009) at day 240 of gestation in MEL compared with CON heifers. Cow uterine artery blood flow was increased (P = 0.003) in MEL compared with CON cows irrespective of gestational day. Maternal and fetal concentrations of melatonin were increased (P < 0.05) in MEL compared with CON heifers. The percent of placentome capillary area per mm2 was decreased (P = 0.019) in MEL compared with CON heifers, while cotyledonary ANGPT1 mRNA tended to increase (P = 0.095) in MEL compared with CON heifers. At weaning, body weight of male offspring and their scrotal circumference were increased (P < 0.05) in calves born to MEL compared with CON dams, while seminiferous tubule diameter and area were not different (P > 0.40) between treatments. In summary, melatonin supplementation increased uterine artery blood flow in mid to late gestating cattle, but this was not accompanied by an increase in fetal weight. Alterations in postnatal development of bulls, including increased body weight and scrotal circumference, warrants future investigations related to attainment of puberty and subsequent fertility of offspring born to melatonin supplemented dams. [ABSTRACT FROM AUTHOR]

Increased colostrum lactose concentration is also associated with greater colostrum yield and reduced protein and Brix% in dairy cattle ([83]), supporting the concept that colostrum yield may dilute component concentrations. Imposing mid to late-gestation nutrient restriction reduced first-milking colostrum yield (within 1 h postcalving) in beef cattle ([56]; [72]) without altering colostrum IgG concentration ([56]; [72]) but compromised total IgG yield ([72]). Colostrum IgG yield is often not reported in dairy and beef cattle, although one study noted that there was no difference in colostrum IgG output between treatments, despite colostrum IgG concentration being decreased ([84]). By contrast to cattle, colostrum yield in sheep appears more sensitive to protein supplementation during late gestation, with most studies indicating that increased protein intake (at times, in conjunction with greater RUP intake) increases colostrum yield ([38]; [3]). Keywords: cattle; colostrum; immunoglobulin G; prepartum; nutrition; sheep EN cattle colostrum immunoglobulin G prepartum nutrition sheep 24 36 13 06/20/23 20230601 NES 230601 Implications Many cattle and sheep do not produce enough colostrum for their offspring. [Extracted from the article]

The objective of this study was to investigate the effects of supplementing dried distillers’ grains plus solubles (DDGS) during late gestation on uterine blood flow (BF), circulating steroid hormones and hepatic steroid metabolizing enzymes, and calf and placental weights. Multiparous beef cows were randomly divided into a control group (CON; n = 15) consuming a diet containing 90% corn stover and 10% corn silage (DM basis) for ad libitum intake and a treatment group (SUP; n = 12) consuming the same diet and DDGS (0.3% of BW). Corn silage inclusion was increased to 30% as gestation progressed to meet increasing caloric requirements. Ipsilateral and contralateral uterine BF and cross-sectional area (CSA) of each uterine artery were measured by Doppler ultrasonography on d 180, 216, and 246 of pregnancy. Contralateral BF and CSA increased (P < 0.01) as gestation advanced. Ipsilateral BF and CSA was affected by a treatment × day of gestation interaction (P < 0.05). A main effect of treatment (P = 0.02) and day (P < 0.01) was observed for total BF; BF increased over time and SUP cows had greater BF than CON cows. Circulating concentrations of both progesterone (P4) and estradiol-17β (E2) were affected by an interaction of treatment and day (P < 0.01). Concentrations of circulating E2 steadily increased throughout the study and were greater in CON cows than in SUP cows by d 242. Concentrations of P4 also increased over time; P4 of CON cows was greater than that of SUP cows by d 242. Uridine 5′-diphospho-glucuronosyltransferase (UGT) and cytochrome P450 1A (CYP1A) activity increased with advancing gestation (P < 0.01). There was greater UGT activity (P < 0.05) and a trend for greater CYP1A activity (P = 0.06) in SUP cows than in CON cows. Activity of cytochrome P450 3A was greater (P < 0.01) in SUP cows and decreased (P < 0.05) with advancing gestation. Supplementing DDGS to cows fed low-quality forage during late gestation increased uterine BF but decreased circulating E2 and P4 concentrations and altered hepatic steroid metabolizing enzyme activity. It was anticipated that enzyme activity would reflect circulating hormone levels; however, our data suggests the observed increases in BF are not driven by alterations in hormone concentration. Therefore, further research is warranted to elucidate the underlying mechanisms. [ABSTRACT FROM AUTHOR]

Our objectives were to evaluate the impacts of providing vitamin and mineral (VTM) supplements to cow-calf pairs during the summer grazing period on cow and calf performance and liver concentrations of minerals. During a two-year period, 727 crossbred cows and their calves (initial cow BW = 601.7 ± 48.1 kg; calf BW = 87.8 ± 5.0 kg; n = 381 in year 1, n = 346 in year 2) from the Central Grasslands Research Extension Center (Streeter, N.D.) were blocked by parity (young [parity 1 to 3], and old [parity 4+]) and randomly assigned to pastures at the beginning of the grazing season (16 in year 1 and 14 in year 2). Pastures were assigned to receive a free-choice VTM supplement (SUPP) or no VTM supplement (CON) from pasture turnout to pasture removal (158 and 156 days in year 1 and 2, respectively). Consecutive day weights were taken from cows and calves at pasture turnout and removal and liver biopsies were collected from a subset of cows at both timepoints and from calves at weaning. Cows were bred via AI 37 to 41 d after pasture turnout and by natural service cleanup bulls for a 70 to 80 d breeding season. Calving and weaning data were collected from the calf conceived and gestated during treatments. Data were analyzed for the effect of VTM treatment (SUPP vs. CON), block of parity, and their interaction using the GLM procedure of SAS with pasture as the experimental unit. Year was considered a random effect in the final analysis. Cow pregnancy success was evaluated using the GLIMMIX procedure in SAS with model terms of VTM treatment, parity, and their interaction with year as a random effect. In year 2, cows in differing days postpartum (DPP) groups at pasture turnout (66.1, 48.8, and 34.5 ± 1.04 DPP for EARLY, MID, and LATE groups, respectively) were selected for liver biopsies with cow as the experimental unit. Cow and calf BW and BW change were not impacted (P ≥ 0.20) by VTM access. Pregnancy rate to AI, overall pregnancy rate, gestating calf birth BW and calving distribution were not affected (P ≥ 0.11) by treatment. Liver concentrations of Se, Cu, and Co were greater (P ≤ 0.002) at pasture removal and weaning for cows and suckling calves that had access to VTM. Cows considered EARLY calving had greater (P = 0.05) concentrations of liver Se compared with LATE calving cows. Although VTM supplementation enhanced concentrations of key minerals in the liver of cow-calf pairs, reproductive and growth performance was not affected. [ABSTRACT FROM AUTHOR]

To determine the effects of poor maternal nutrition on the growth and metabolism of offspring into maturity, multiparous Dorset ewes pregnant with twins (n = 46) were fed to either 100% (control; n = 13), 60% (restricted; n = 17), or 140% (over; n = 16) of National Research Council requirements from day 30 ± 0.02 of gestation until parturition. Offspring of these ewes are referred to as CON (n = 10 ewes; 12 rams), RES (n = 13 ewes; 21 rams), or OVER (n = 16 ewes; 13 rams), respectively. Lamb body weights (BW) and blood samples were collected weekly from birth (day 0) to day 28 and then every 14 d until day 252. Intravenous glucose tolerance test (infusion of 0.25 g dextrose/kg BW) was performed at day 133 ± 0.25. At day 167 ± 1.42, individual daily intake was recorded over a 77 d feeding period to determine residual feed intake (RFI). Rams were euthanized at day 282 ± 1.82 and body morphometrics, loin eye area (LEA), back fat thickness, and organ weights were collected. The right leg was collected from rams at necropsy and dual-energy x-ray absorptiometry was used to determine bone mineral density (BMD) and length. Averaged from day 0 until day 252, RES and OVER offspring weighed 10.8% and 6.8% less than CON offspring, respectively (P ≤ 0.02). When adjusted for BW, liver and testes weights tended to be increased and decreased, respectively, in RES rams compared with CON rams (P ≤ 0.08). Additionally, RES BMD and bone length were less than CON rams (P ≤ 0.06). Treatment did not influence muscle mass, LEA, or adipose deposition (P ≥ 0.41). Rams (−0.17) were more feed efficient than ewes (0.23; P < 0.01); however, no effect of maternal diet was observed (P ≥ 0.57). At 2 min post glucose infusion, glucose concentrations in OVER offspring were greater than CON and RES offspring (P = 0.04). Concentrations of insulin in CON rams tended to be greater than OVER and RES ewes at 5 min (P ≤ 0.07). No differences were detected in insulin:glucose or area under the curve (AUC) for glucose or insulin (P ≤ 0.29). Maternal diet did not impact offspring triglycerides or cholesterol (P ≤ 0.35). Pre-weaning leptin tended to be 70% greater in OVER offspring than CON (P ≤ 0.07). These data indicate that poor maternal nutrition impairs offspring growth throughout maturity but does not affect RFI. Changes in metabolic factors and glucose tolerance are minimal, highlighting the need to investigate other mechanisms that may contribute to negative impacts of poor maternal diet. [ABSTRACT FROM AUTHOR]

The objective was to evaluate the effects of peripartum supplementation of a methionine hydroxy analogue (MHA) to primiparous, spring-calving beef females on dam and progeny performance. Angus heifers (n  = 60) were blocked by expected parturition date, stratified by body weight (BW) and body condition score (BCS), and randomized to 1 of 15 pens. Pens were randomly assigned to 1 of 3 dietary treatments: a basal diet supplemented with 0 (M0), 15 (M15), or 30 (M30) g/animal/d of MHA (provided as MFP feed supplement, Novus International Inc. St. Charles, MO). Diets were fed from 45 ± 13 (SD) d pre-calving through 81 ± 13 d postpartum (DPP), after which all cow–calf pairs were managed as a single group on pasture until weaning (199 ± 13 DPP). Dam BW, BCS, and blood samples were taken at 6 predetermined timepoints. Progeny data were collected at birth, 2 intermediate timepoints, and at weaning. Milk samples were collected for composition analysis at 7 ± 2 DPP and at 55 ± 5 DPP. Serial progesterone samples were analyzed to establish resumption of cyclicity, and ultrasonography was performed at 55 ± 5 DPP to evaluate ovarian function. Cows were bred via artificial insemination at 82 ± 13 DPP and subsequently exposed to bulls for a 55-d breeding season. Pen was the experimental unit, and preplanned orthogonal contrasts were tested (linear effect and M0 vs. M15 + M30). Dam BW and BCS were not affected by treatment (P  ≥ 0.29) throughout the study. Week 1 milk fat concentration increased linearly (P  = 0.05) and total solids tended to increase linearly (P  = 0.07) as MHA increased; however, no other milk components were affected (P  ≥ 0.16). Treatment did not affect (P  ≥ 0.16) dam reproductive parameters or progeny growth from birth until weaning. Post-calving, circulating methionine equivalents tended to linearly increase (P  = 0.10) with increasing MHA supplementation. At breeding, plasma urea N linearly decreased (P  = 0.03) with increased supplementation of MHA, and plasma non-esterified fatty acids were less (P  = 0.04) in MHA-supplemented dams compared with dams receiving no MHA. Maternal circulating glucose, glutathione peroxidase, and thiobarbituric acid-reactive substances were not affected (P  ≥ 0.15) by treatment at any point. These data indicate that peripartum supplementation of MHA may increase milk fat composition shortly after calving, but MHA supplementation did not improve progeny growth or dam reproductive performance in the current study. [ABSTRACT FROM AUTHOR]

This experiment evaluated the effects of supplementing narasin during late-gestation and lactation on productive and physiological responses of Bos indicus beef heifers and their offspring. Pregnant, nulliparous Nelore heifers (N = 88) that conceived under the same fixed-time artificial insemination protocol and to the same sire were used. Heifers were ranked by maternal ability genomic score, body weight (BW) and body condition score (BCS) and allocated to 44 drylot pens (2 heifers per pen; 10 × 25 m). Pens were ranked by these traits and alternatively assigned to receive (NAR) or not (CON) 0.260 mg of narasin/kg of heifer BW daily (Elanco Saúde Animal, São Paulo, Brazil). Narasin was mixed into a supplement offered at 0.30% of heifer BW from day 0 until heifers weaned their calves (day 316), whereas CON heifers received the same supplement without narasin addition. Heifers received Urochloa brizantha hay and water for ad libitum consumption (days 0 to 316) and calved between days 97 to 112 of the experiment. After calving, heifers and offspring had access to hay and supplement; hence, supplements and narasin were offered according to heifer + calf BW beginning on day 162. No treatment differences were detected (P ≥ 0.18) for heifer BW and BCS during the experiment, although BW loss from day 0 to calving was less (P = 0.04) in NAR compared to CON heifers. Hay intake during the experiment did not differ (P = 0.79) between treatments. Serum IGF-I concentrations were greater (P = 0.05) for NAR heifers on day 60 of the experiment and did not differ (P ≥ 0.28) between treatments 24 h and 30 d after calving (treatment × day interaction; P = 0.04). No treatment effects were detected (P ≥ 0.58) for calf birth BW. Serum concentrations of total protein 24 h after birth were greater (P = 0.04) in calves from NAR compared with CON heifers, and a tendency (P = 0.10) for a similar outcome was noted for serum IgG concentrations. Diarrhea incidence did not differ (P = 0.16) between treatments, although the number of total diarrhea cases per calf were greater (P = 0.03) in the CON offspring. Growth rate of calves from NAR heifers tended (P = 0.08) to be greater, resulting in heavier calves at weaning (P ≤ 0.04) compared with CON offspring. Collectively, these outcomes indicate narasin supplementation to beef heifers as a nutritional alternative to improve cow–calf productivity via developmental programming effects during gestation, as well as direct consumption by their nursing offspring. [ABSTRACT FROM AUTHOR]

Feeding rumen-protected choline (RPC) to late gestation dairy cows has potential to affect growth in offspring. The objective of this study was to evaluate the effects of in utero choline exposure on the growth, feed efficiency (FE), metabolism, and carcass quality of Angus × Holstein cattle. Multiparous Holstein cows pregnant with male (N = 17) or female (N = 30) Angus-sired calves were enrolled 21 d prepartum and randomly assigned to one of four dietary treatments varying in quantity and formulation of RPC. The treatments included a control with 0 g/d supplemental RPC (CTL), supplemental RPC fed at the recommended dose (RD) of 15 g/d from either an established RPC product (RPC1RD; ReaShure; Balchem Corp.) or choline ion from a concentrated RPC prototype (RPC2RD; Balchem Corp.), or a high dose (HD) of RPC2 fed at 22 g/d (RPC2HD). From 2 to 6 mo of age, calves were group housed and offered 2.3 kg grain/hd/d (42% CP) with ad libitum grass hay, and stepped up to a complete finishing diet by 7 mo (12.0% CP; 1.34 Mcal/kg NEg). Weight and height were measured monthly. Animal FE was measured in individual pens for 35 d at 8 mo. Feed intake was measured daily, and blood was obtained on day 18 during the FE period. Afterwards, cattle were group housed and offered a free-choice finishing diet until slaughter, where carcass yield and quality characteristics were measured. Mixed models were used in PROC MIXED (SAS, 9.4) with the fixed effects of treatment, sex, time, their interactions, and the random effect of calf. Month was the repeated measure, and preplanned contrasts were used. Blood and FE data were analyzed with the fixed effect of dam choline treatment, calf sex, and the interaction. Increasing dose of RPC tended to increase weight over the entire study period. Feeding any RPC increased hip and wither height compared with CTL, and increasing RPC dose linearly increased hip and wither height. Treatment and sex interacted on DMI whereby increasing RPC intake linearly increased DMI for males but not females. Compared with control, feeding any RPC decreased plasma insulin, glucose, and an insulin sensitivity index (RQUICKI). In utero choline exposure increased kidney–pelvic–heart fat and marbling score. Mechanisms of action for intrauterine choline exposure on offspring growth, metabolism, and carcass characteristics should be explored as they have direct implications for profitability for cattle growers and feeders. [ABSTRACT FROM AUTHOR]

Fall-calving primiparous beef females [body weight: 451 ± 28 (SD) kg; body condition score: 5.4 ± 0.7] were individually-fed either 100% (control; CON; n = 13) or 70% (nutrient restricted; NR; n = 13) of metabolizable energy and metabolizable protein requirements for maintenance, pregnancy, and growth from day 160 of gestation to parturition. Calves were reared naturally by their dams and monitored for latency times from birth to first sternal recumbency, attempt to stand, and stand; vigor scores were assigned at 2, 5, 10, and 20 min of age. Rectal temperatures and jugular blood were obtained at 0 (pre-suckling), 6, 12, 24, and 48 h of age, and blood chemistry, hematology, cortisol, and insulin were determined. Data were analyzed with fixed effects of late gestational nutritional plane (single data point) or nutritional plane, hour, and their interaction (data over time, repeated measures). Calving date was a fixed effect; calf sex was included when P < 0.25. We previously reported that late gestational nutritional plane did not affect gestation length or calf size at birth, but calving assistance and fetal malpresentation occurred more often in NR. Nutritional plane did not affect (P = 0.65) duration of parturition, but calves born to NR dams had slower times to attempt to stand (P = 0.09), slower times to stand (P = 0.02), and poorer 20 min vigor scores (P = 0.05). Serum immunoglobulin G and A concentrations at 48 h were greater (P ≤ 0.03) for NR calves. Rectal temperature of NR calves was less (P = 0.02) at 0 h, but greater (P = 0.04) at 24 h compared with CON. Circulating glucose, non-esterified fatty acids, triglycerides, cortisol, and insulin were not affected by nutritional plane (P ≥ 0.18). Total protein and globulin from 6 to 48 h were greater (P ≤ 0.02) in NR calves. Calves from NR dams had greater (P ≤ 0.08) gamma-glutamyl transferase at 6, 12, and 48 h. Serum aspartate aminotransferase was greater (P ≤ 0.07) from 0 to 24 h and creatine kinase was greater (P ≤ 0.04) from 6 to 24 h in NR calves. At 0 h, potassium was greater (P = 0.03) in NR calves. Calves born to CON had greater chloride (P = 0.08; main effect), sodium (P ≤ 0.09) from 0 to 48 h, and anion gap (P = 0.02) at 6 h. Hematocrit from 6 to 24 h and red blood cells and hemoglobin at 6 and 12 h were greater (P ≤ 0.09) in CON calves. These data indicate that nutrient restriction during late gestation resulted in less vigorous calves with more indicators of trauma in early life. [ABSTRACT FROM AUTHOR]

Fall-calving primiparous crossbred beef females [body weight (BW): 451 ± 28 (SD) kg; body condition score (BCS): 5.4 ± 0.7] were allocated by fetal sex and expected calving date to receive either 100% (control; CON; n = 13) or 70% (nutrient restricted; NR; n = 13) of metabolizable energy and metabolizable protein requirements for maintenance, pregnancy, and growth from day 160 of gestation to calving. Heifers were individually-fed chopped poor quality hay and supplemented to meet targeted nutritional planes based on estimated hay intakes. Dam BW, BCS, backfat, and metabolic status were determined pre-treatment, every 21 d (BW and metabolic status) or 42 d (BCS and backfat) during gestation, and post-calving. At birth, calf BW and size were measured, and total colostrum from the most full rear quarter was collected pre-suckling. Data were analyzed with nutritional plane, treatment initiation date, and calf sex (when P < 0.25) as fixed effects. Gestational metabolites included day and nutritional plane × day as repeated measures. During late gestation, CON dams gained (P < 0.01) maternal (non-gravid) BW and maintained (P ≥ 0.17) BCS and backfat, while NR dams lost (P < 0.01) maternal BW, BCS, and backfat. Circulating glucose, urea N, and triglycerides were less (P ≤ 0.05) in NR dams than CON at most late gestational timepoints after treatment initiation. Circulating non-esterified fatty acids were greater (P < 0.01) in NR dams than CON. Post-calving, NR dams weighed 63.6 kg less (P < 0.01) and were 2.0 BCS less (P < 0.01) than CON. At 1 h post-calving, NR dams had less (P = 0.01) plasma glucose and tended to have less (P = 0.08) plasma triglycerides than CON. Nutrient restriction did not affect (P ≥ 0.27) gestation length, calf birth weight, or calf size at birth. Colostrum yield was 40% less (P = 0.04) in NR dams than CON. Protein and immunoglobulin concentrations were greater (P ≤ 0.04), but free glucose and urea N concentrations were less (P ≤ 0.03), in colostrum of NR dams than CON. Colostrum total lactose, free glucose, and urea N were less (P ≤ 0.03) in NR dams than CON, but total protein, triglycerides, and immunoglobulins were not affected (P ≥ 0.55). In summary, beef heifers experiencing late gestational nutrient restriction prioritized partitioning nutrients to fetal growth and colostrum production over maternal growth. During undernutrition, fetal and colostral nutrient demands were largely compensated for by catabolism of maternal tissue stores. [ABSTRACT FROM AUTHOR]

Changes in the environment, including nutritional changes, can influence fetal and postnatal development of the offspring, which can result in differences in growth, metabolism, reproduction, and health later in life. In beef cattle research on energy and protein restriction during late gestation appears to be contradictory. Therefore, in this review, we will examine the nutrient requirements recommended for this period. We are summarizing contradictory data on effects on offspring performance with possible explanations of the reason for why the data seems contradictory. We will finish by discussing some areas that we consider important for further research to increase the knowledge on how maternal nutrition influences offspring development. In particular, suggestions are provided on the need for more accurately measuring nutrient and energy supply and use and the impact on subsequent epigenetic effects. This will improve understanding of nutritional effects during gestation on offspring performance. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine whether a high‐fat diet (HFD) fed to goats for a brief period during peri‐conception would optimize reproductive and foetal responses. Thirty‐four Anglo‐Nubian crossbred adult goats were allocated into three groups: control (n = 11), fed with a total mixed ration (TMR) based on chopped elephant grass and concentrate; HFBM (n = 11), given TMR supplemented with soybean oil on a 0.5% dry matter basis for 11 days starting nine days before mating (BM); and HFAM (n = 12), fed with soybean oil included in the TMR for 15 days after mating (AM). The TMR diets differed in their fat content (7.5% vs. 2.9%). All goats had oestrus synchronized for 14 days BM by intravaginal administration of 60 mg MPA sponge for 12 days. Forty‐eight hours BM, the sponge was removed and 0.075 mg PGF2α was applied intramuscularly. After 36 h, 1 ml GnRH was administered intramuscularly, and goats were mated after sponge removal. The fat groups showed lower feed intake (p <.001) and higher cholesterol levels (p <.001) when HFD was administered. Doppler and B‐mode ultrasound evaluations revealed a greater (p <.05) number of small (<3 mm, 10 ± 0.6 vs. 8 ± 0.5) and large (≥3 mm, 6 ± 0.4 vs. 5.0 ± 0.2) follicles and intraovarian blood area (p <.05) in the HFBM group during sponge removal (57.6%) and mating (24.2%) than those of the no‐fat group. During AM, the fat‐fed groups exhibited higher glutathione peroxidase levels (p <.05) and a reduction (p <.001) in corpus luteum size (19%) and vascularized Doppler area (41%). No difference (p >.05) between groups was found in foetal traits, placentome and umbilical vascular development, except for the embryonic vesicle where HFAM twin pregnancy showed a smaller size than the control (26.1 ± 3.5 cm vs. 33.7 ± 2.7 cm; p <.01). Thus, HFD applied during peri‐conception of goats has no impact on later foetal development but improved the follicular growth when given before the mating. Thus, the use of HFD in periconception has no impact on foetal development but increases follicular growth before breeding time. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effect of mixed feed sorghum-Indigofera on Garut ewes reproductive performance stimulated with Pregnant Mare Serum Gonadotropin (PMSG) hormone. Twenty-eight multiparous Garut ewes were grouped based on feed type (local forage (LF) vs. mixed feed sorghum-Indigofera (SI)), for a 30-day acclimatization period with a completely randomized design. Following acclimatization, all animals were synchronized with PGF2a (i.m.) twice, 11 days apart. Half the population of each group was stimulated with 500 IU PMSG after the second injection. Estrous characteristics were observed for seven days, followed by natural mating. Pregnancy status and the number of fetuses were detected 30 days after mating using ultrasound (USG), and reproductive efficiency was evaluated after parturition. Data during acclimatization were analyzed using a two-sample t-test, while the reproductive performances used a General Linear Model (GLM). Estrous characteristics showed no interaction (p>0.05) between feed types and PMSG stimulation. The onset of estrous in the SI treatment occurred 9.33 hours faster (p<0.05) than in the LF treatment. Meanwhile, the duration of estrous in the group stimulated with PMSG was 18.67 hours longer (p<0.05) than without PMSG. The vulva temperature at standing heat was 38.16±0.69 °C (p>0.05), with the pregnancy rate ranging 42.85%-100%. Interestingly, the SI group treated with or without PMSG had a larger litter size (1.43-4.50) compared to the LF group (1.25-1.33). It is concluded that feeding with SI had improved reproductive success, with the highest number of ewes giving birth. Additionally, the ewes fed SI with PMSG had the largest litter size. [ABSTRACT FROM AUTHOR]

To determine the effect of calving season on perinatal nutrient availability and neonatal beef calf vigor, data were collected from 4 spring- (average calving date: February 14; n = 203 total) and 4 fall- (average calving date: September 20; n = 179 total) calving experiments. Time to stand was determined as minutes from birth to standing for 5 s. After birth, calf weight and size (length, heart and abdominal girth, and cannon circumference) were recorded. Jugular blood samples and rectal temperatures were obtained at 0, 6, 12, and 24 h postnatally in 6 experiments and at 48 h postnatally in Exp. 2 to 8. Data were analyzed with fixed effects of season (single point) or season, hour, and their interaction (over time, using repeated measures). Experiment was a random effect; calf sex was included when P ≤ 0.25. Within calving season, correlations were determined between calf size, vigor, and 48-h serum total protein. Fall-born calves tended to have lighter (P = 0.09) birth weight and faster (P = 0.05) time to stand than spring-born calves. Season did not affect (P ≥ 0.18) gestation length, other calf size measures, or 48-h serum total protein. Fall-born calves had greater (P ≤ 0.003) rectal temperature at 0, 24, and 48 h postnatal. Spring-born calves had greater (P ≤ 0.009) circulating glucose at 0 h, serum non-esterified fatty acids at 0 and 6 h, and plasma triglycerides at 0, 6, 12, and 48 h. Fall-born calves had greater (P ≤ 0.03) sodium from 6 to 48 h and magnesium from 0 to 24 h of age. Phosphorus was greater (P ≤ 0.02) at 6 and 12 h of age in spring-born calves. Spring-born calves had greater (P ≤ 0.04) aspartate aminotransferase at 12 and 24 h and creatine kinase at 0 and 12 h of age. Fall-born calves had greater (P ≤ 0.03) albumin, calcium, and chloride, had lower (P ≤ 0.03) bicarbonate and direct bilirubin, and tended to have greater (P = 0.10) anion gap (all main effects of calving season). Calf birth weight had a weak positive relationship (P ≤ 0.03) with 48-h serum total protein and time to stand in fall-born, but not spring-born, calves. Overall, fetal growth was restricted and neonatal dehydration was increased by warm conditions for fall-born calves, but vigor and metabolism were negatively affected by cold conditions in spring-born calves. These data suggest that calving season influences perinatal nutrient availability, which may impact the transition of beef calves to postnatal life. [ABSTRACT FROM AUTHOR]

The circadian system is an inbuilt timekeeping mechanism that tracks the 24-h day through the generation of circadian rhythms. Circadian rhythms enable animals to forecast and anticipate regular changes in their environment, and orchestrate biochemical, physiological and behavioral events so that the right process occurs at the right time. The 24 h rhythms generated by circadian clocks are integrated into homeostatic feedback loops and repair pathways. Metabolic and reproductive systems are highly integrated with the circadian timing system and demonstrate reciprocal regulation. Circadian clocks set the timing of circadian rhythms by gathering temporal information from external and internal signals to include light and nutrients. Exogenous and endogenous factors that function as inputs to the circadian clocks can disrupt their timing when applied at unusual and inappropriate times, and are referred to as chronodisruptors. Changes in the natural light-dark cycle perturb the circadian system. Other chronodisrupters include inappropriately timed food intake and physical activity and biological stress. Knowledge of the biology underlying circadian clock timing is critical to understanding how to maximize health and production effciency of cattle. Here we review circadian clocks and their function in the regulation of metabolic and reproductive systems as well as the consequence of circadian disruption on mammary development and lactation with a particular focus on recent research fndings from studies of dairy cows. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of a flushing diet containing docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) from lemuru fish oil in ewe ration on colostrum quality and lamb performance. Twenty Garut ewes were divided into four treatments of flushing concentrate: control concentrate (P1), flushing concentrate containing 6% palm oil (P2), flushing concentrate containing 3% lemuru oil and 3% palm oil (P3), flushing concentrate containing 6% lemuru oil (P4). The animal consumed Napier grass and concentrate with a diet ratio of 30%:70% based on dry matter. The experimental ewes were fed flushing rations two weeks before and two weeks after mating continued with 2 weeks before and two weeks after lambing. The ewes and their lambs were put together until weaning time with around two months. The parameters observed in ewes were nutrient consumption and their colostrum qualities. Meanwhile, the lamb parameters measured were nutrient consumption, lamb blood metabolites at birth, and lamb performance. The experimental design used a randomized blocked design (RBD). Analysis of variance (ANOVA) followed by Duncan test was used to analyze data. The results showed that treatment did not significantly affect dry matter consumption in ewe and lamb, ewe's colostrum quality, and lamb's blood metabolites. However, the treatment significantly improved (p<0.05) average daily gain and weaning weights of lambs. In conclusion, the flushing ration did not affect the quality of colostrum produced. Feeding of experimental ewes 2 weeks before and 2 weeks after mating continued with 2 weeks before and 2 weeks after parturition with flushing rations of 6% lemuru oil containing EPA and DHA can produce twin lambs with good growth performances such as daily gain and weaning weight similar to the control, which has single litter size. [ABSTRACT FROM AUTHOR]

We hypothesized that gestational nutrition would affect calf feed efficiency and small intestinal biology, which would be correlated with feed efficiency. Multiparous beef cows (n = 36) were individually fed 1 of 3 diets from d 45 to 185 of gestation: native grass hay and supplement to meet NRC recommendations (control [CON]), 70% of CON NEm (nutrient restricted [NR]), or a NR diet with a RUP supplement (NR+RUP) to provide similar essential AA as CON. After d 185 of gestation, cows were managed as a single group, and calf individual feed intake was measured with the GrowSafe System during finishing. At slaughter, the small intestine was dissected and sampled. Data were analyzed with calf sex as a block. There was no effect (P ≥ 0.33) of maternal treatment on residual feed intake, G:F, DMI, ADG, or final BW. Small intestinal mass did not differ (P ≥ 0.38) among treatments, although calf small intestinal length tended (P = 0.07) to be greater for NR than NR+RUP. There were no differences (P ≥ 0.20) in calf small intestinal density or jejunal cellularity, proliferation, or vascularity among treatments. Jejunal soluble guanylate cyclase mRNA was greater (P < 0.03) for NR+RUP than CON and NR. Residual feed intake was positively correlated (P ≤ 0.09) with small intestinal mass and relative mass and jejunal RNA content but was negatively correlated (P ≤ 0.09) with jejunal mucosal density and DNA concentration. Gain:feed was positively correlated (P≤0.09) with jejunal mucosal density, DNA, protein, and total cells and was negatively correlated (P < 0.05) with small intestinal relative mass, jejunal RNA, and RNA:DNA. Dry matter intake was positively correlated (P ≤ 0.09) with small intestinal mass, relative mass, length, and density as well as jejunal DNA and protein content, total cells, total vascularity, and kinase insert domain receptor and endothelial nitric oxide synthase 3 mRNA and was negatively correlated (P = 0.02) with relative small intestinal length. In this study, calf performance and efficiency during finishing as well as most measures of small intestinal growth were not affected by maternal nutrient restriction during early and midgestation. Results indicate that offspring small intestinal gene expression may be affected by gestational nutrition even when apparent tissue growth is unchanged. Furthermore, small intestinal size and growth may explain some variation in efficiency of nutrient utilization in feedlot cattle. [ABSTRACT FROM AUTHOR]

Poor maternal nutrition during gestation can result in reduced offspring muscle growth and altered muscle metabolism. We hypothesized that over- or restricted-nutrition during gestation would alter the longissimus dorsi muscle (LM) proteome of offspring. Pregnant ewes were fed 60% (restricted), 100% (control), or 140% (over) of National Research Council requirements for total digestible nutrients from day 30 of gestation until parturition. Fetal (RES, CON, OVER) LM were collected at days 90 and 135 of gestation, or from offspring within 24 h of birth. Sarcoplasmic proteins were isolated, trypsin digested, and subjected to multiplexed, label-based quantitative mass spectrometry analysis integrating tandem mass tag technology. Differential expression of proteins was identified by ANOVA followed by Tukey's HSD post hoc tests, and regularized regression via the elastic net. Significance was set at P < 0.05. Over-represented pathways containing differentially expressed proteins were identified by Reactome and included metabolism of proteins, immune system, cellular response to stress/external stimuli, developmental biology, and infectious disease. As a result of maternal diet, a total of 312 proteins were differentially expressed (day 90 = 89 proteins; day 135 = 115 proteins; birth = 131 proteins). Expression of eukaryotic initiation factor (EIF) 2S3, EIF3L, and EIF4G2 was lower in OVER fetuses at day 90 of gestation (P < 0.05). Calcineurin A and mitogen-activated protein kinase 1 were greater in RES fetuses at day 90 (P < 0.04). At day 135 of gestation, pyruvate kinase and lactate dehydrogenase A expression were greater in OVER fetuses than CON (P < 0.04). Thioredoxin expression was greater in RES fetuses relative to CON at day 135 (P = 0.05). At birth, proteins of the COP9 signalosome complex were greater in RES offspring relative to OVER (P < 0.05). Together, these data indicate that protein degradation and synthesis, metabolism, and oxidative stress are altered in a time and diet-specific manner, which may contribute to the phenotypic and metabolic changes observed during fetal development and postnatal growth. [ABSTRACT FROM AUTHOR]