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Simple Summary: The nutritional management of pregnant females can have lasting impacts on offspring growth, health, and well-being during postnatal life. Providing supplemental vitamins and minerals during pregnancy may influence offspring development and immune function. In two experiments, we investigated the impacts of supplementing vitamins and minerals to pregnant beef heifers on immunological components of maternal colostrum and resultant calf immunoglobulins in serum after consuming maternal colostrum or a colostrum replacement product. Antibody titers in blood from calves were also evaluated in response to receiving vaccinations through weaning. We observed no influence of maternal supplementation on colostral immunoglobulins or calf serum immunoglobulins 24 h after consuming colostrum, but calves receiving colostrum from their dams had greater immunoglobulin concentrations in their serum compared with calves receiving a colostrum replacer. Additionally, calves born to vitamin and mineral supplemented dams had increased titer responses to vaccination at weaning compared with calves born to non-supplemented dams. These data indicate that supplementary vitamins and minerals to gestating beef heifers may be a critical factor in programming offspring immune system development, ensuing animal health, and supporting profitability in beef operations. Two experiments assessed the effects of providing a vitamin and mineral supplement to gestating beef heifers on concentrations of immunoglobulins (Ig) in colostrum and calf serum 24 h after feeding maternal colostrum (Exp. 1) or a colostrum-replacement product (Exp. 2). Angus-based heifers (n = 31, Exp. 1; n = 14, Exp. 2) were fed a basal diet (CON) or were fed a basal diet plus a vitamin and mineral supplement (VTM) from breeding (Exp. 1) or 60 d pre-breeding (Exp. 2) through calving. Colostrum was collected at calving, and serum was collected from calves 24 h after colostrum consumption to evaluate passive transfer. Serum was collected from calves in Exp. 1 to determine serum titers in response to vaccination at birth, pasture turn out, weaning, and 14 d after vaccination. Concentrations of IgG, IgM, or IgA in colostrum or in calf serum at 24 h were not impacted by dam treatment (p ≥ 0.21); however, concentrations of Ig in calf serum at 24 h were greater (p ≤ 0.01) in calves receiving maternal colostrum than those receiving a colostrum replacer. Calves born to VTM heifers had greater antibody titers at birth, pasture turn out, and weaning for infectious bovine rhinotracheitis (IBR), bovine viral diarrhea virus type 2 (BVD-2), and bovine respiratory syncytial virus (BRSV), respectively. Our results suggest that the programming of immune function in calves via prenatal nutrition appears to extend postnatally in CON and VTM offspring. [ABSTRACT FROM AUTHOR]

Background: Sustainable rangeland management balances production and conservation. While a broad literature describesthe conservation benefits of prescribed fire, benefits for livestock production have emerged more slowly. Mineral nutrition is important for livestock health and performance, but the impact of prescribed fire on mineral concentration of forages, especially in the northern US Great Plains, remains unknown. Aims: We investigated how burning affects the mineral concentration of forage early and late in the growing season. Methods: Data were collected on mixed-grass prairie in south-central North Dakota, USA. Vegetation was clipped from recently burned, 1 year post-fire, 2 years post-fire, and not-yet-burned patches at the same sampling points in spring and late summer. Samples were analysed for calcium, phosphorus, magnesium, potassium, copper, iron, manganese, and zinc concentration. Key results: Burning increased forage mineral concentration across most minerals. Phosphorous, potassium, copper and zinc were higher in burned areas in late spring and summer; calcium, magnesium and manganese were only higher during the late summer; Late-season iron levels increased with time since fire. Conclusions: Prescribed fire has a positive effect on forage mineral content. Implications: Prescribed fire has the potential to reduce mineral supplementation costs and improve cow performance. Prescribed fire has a positive effect on forage mineral content and has the potential to reduce mineral supplementation costs and improve cow performance. [ABSTRACT FROM AUTHOR]

Our aim was to investigate the effects of maternal (F0) body weight (BW) gain during the first 84 d of gestation on body composition, ovarian reserve, and hormonal and metabolic parameters of breeding-age F1 heifers, as well as the BW and morphometry of F2 fetuses. The study also evaluated the effect of maternal BW gain (F0) on the mRNA relative abundance of the small intestine of both F1 heifers and F2 fetuses. Crossbred Angus heifers (F0; n  = 100) were managed to gain 0.20 kg/d (low gain [ LG ], n  = 50) or 0.75 kg/d (moderate gain [ MG ], n  = 50) for the first 84 d of gestation. Subsequently, F0 dams were managed on a common forage-based diet for the rest of gestation until the weaning of the F1 offspring. At 15 mo of age, a subset of F1 heifers was randomly selected for the current experiment (n  = 8 LG and n  = 8 MG). Heifers were bred via artificial insemination (AI ; day 0), then harvested on day 84 of gestation. On days −10, 42, and 84, BW was recorded, and blood was collected and analyzed for concentrations of glucose, non-esterified fatty acids, progesterone, insulin, and insulin-like growth factor-1. The weight of F1 carcasses, organs, gravid uteri, and F2 fetuses and organs were recorded at harvest. Visible follicles were counted on F1 ovaries at harvest, and histology was used to count microscopic follicles. Liver and jejunal samples from F1 heifers were collected to measure tissue oxygen consumption and jejunal samples from F1 heifers and F2 fetuses were collected for mRNA relative abundance analysis. BW of F1 heifers from MG dams tended to be 12 kg greater (P  = 0.06) than for F1 heifers from LG dams. Concentrations of glucose were greater (P  = 0.03) in F1 heifers from the MG group, with no differences in other blood metabolites or follicular populations (P  ≥ 0.16). Interestingly, mammary glands were heavier (P  = 0.05), and placentas and body depth tended to be heavier and greater, respectively (P  ≤ 0.10), for F2 fetuses from F0 LG heifers. Oxygen consumption in the liver and jejunum, as well as mRNA relative abundance in the jejunum of F1 heifers, were not affected by F0 rate of gain (P  ≥ 0.16). However, the NDUFC1 , SDHA , UQCR1 , and PPARG genes were upregulated (P  ≤ 0.05) in the jejunum of F2 fetuses from the LG group. In conclusion, BW gain of F0 heifers during early gestation exerts subtle effects on pre-breeding BW and blood metabolites in F1 offspring, with impacts present in F2 placenta, mammary gland, and intestine. [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]

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]

We evaluated the effects of feeding 60% dried corn distillers' grains plus solubles (DDGS) or the equivalent sulfur as CaSO4 on sperm characteristics and transcript abundance. Thirty-six half-sibling Angus bulls (256 ± 8.5 d; initial BW = 320 ± 2.7 kg) were assigned to one of three treatments: (1) 60% concentrate as corn (CON); (2) 60% DDGS as corn replacement (60DDGS); and (3) CON diet + equivalent sulfur of 60DDGS added as CaSO4 (SULF). The acrosome/cell membrane integrity, mitochondrial energy potential, oxidation status, DNA integrity, and zinc signatures were analyzed via flow cytometry. Sperm-specific gene expression was assessed via RNA sequencing. The flow cytometry data were analyzed using PROC MIXED in SAS to determine the effects of treatment. Pairwise comparisons based on edgeR were used to identify differentially expressed genes. The percentage of polarized mitochondria tended to be greater (p = 0.08) for SULF compared with CON and 60DDGS. Protamine 1 was upregulated (p < 0.01; FDR = 0.10) in 60DDGS compared to CON. Zinc signature 1 in 60DDGS and SULF was reduced (p = 0.03) compared to CON. This study suggests that feeding bulls diets containing 60% DDGS had little effect on DNA integrity and gene expression. [ABSTRACT FROM AUTHOR]

Field pea production in North Dakota has increased significantly over the past 20 yr with hectares planted increasing by more than 68% over that period. With the increase in supply of field peas, there is interest in evaluating whether using field peas in beef cattle finishing rations is economical compared with commonly used ingredients such as corn DDGS. This 2-yr study was conducted to a) determine the economic potential of field peas relative to corn DDGS in growing heifer diets, and b) identify price points for competitive utilization of field peas as an alternative to corn DDGS in growing heifer diets. Each year, 162 heifers were kept in six dry lot pens and fed isocaloric and isonitrogenous corn DDGS-based or field peabased total mixed rations in the fall and winter. Heifer performance data analysis considered the fixed effects of diet (corn DDGS or field peas), season (fall and winter), and diet x season interaction. Economic evaluation of feed costs for each total mixed ration (TMR) was based on the 2-yr average measures of dry matter intake (DMI) and total body weight (BW) gain. Sensitivity analysis was conducted to calculate relative total cost of feeding field peas versus corn DDGS for a number of combinations of prices of corn DDGS and field peas. Heifer final BW, total BW gain, and daily BW gains (ADG) were not impacted (P > 0.05) by diet when 0.33 kg. d-1 and 0.48 kg. d-1 of corn DDGS and field peas were incorporated into corn DDGS-based and field peas-based TMR, respectively. Seasonal differences in heifer performance showed greater (P < 0.001) DMI in winter relative to fall and greater (P < 0.001) total BW gain and ADG in the fall relative to winter. The relative value of field peas was mainly driven by amount of field peas incorporated into diets and price of field peas relative to corn DDGS. Overall, for a base-case average price of $325 MT-1 for corn DDGS, the breakeven price for field peas was equal to $231.15 MT-1, which was 36.8% less than the base-case price of $366 MT-1 for field peas, and 71% of the base-case price of corn DDGS. Conversely, for the base-case price of field peas of $366, the breakeven price of corn DDGS was equal to $514.60 MT-1, which was 58.3% more than the base-case price of $325 MT for corn DDGS and 140.6% more than the base-case price for field peas. Results show that there are economic benefits of including field peas in cattle rations when there is excess field peas production available at competitive prices and offer useful economic information to the field pea processing industry about the range of prices that beef cattle producers can afford to pay for field peas relative to corn DDGS. [ABSTRACT FROM AUTHOR]

Despite the increased appreciation of the involvement of maternal nutrition in fetal development, its effects on jejunum programming remain largely unexplored. Here, we investigated the impact of maternal vitamin and mineral supplementation throughout gestation on the differential gene expression and underlying biological pathways in the jejunum of neonatal calves. For this, beginning 60 d before breeding and continuing throughout gestation, crossbred Angus heifers (n = 14) were fed either a basal diet (CON; n = 7) or the basal diet plus 113 g•heifer-1•d-1 of VTM supplement (VTM; n = 7). All heifers were gestating female calves, which were euthanized 30 h after birth. Samples of jejunum mucosa were collected, stored at -80°C, then subjected to total RNA isolation and RNA sequencing. After quality control, the reads were mapped using STAR aligner and differentially expressed genes (DEGs) were identified using DESeq2. Maternal VTM supplementation did not affect calf organ mass, including jejunum weight. However, high-resolution respirometry analysis revealed greater mitochondrial efficiency in jejunum of calves from VTM supplemented dams. Additionally, we identified 528 DEGs between the VTM and CON calves (P-value ≤ 0.05 and |log2FC| > 0.5). Among them, the genes IGFBP2 and IGFBP6, which are key genes in insulin pathway and involved in regulation of insulinlike growth factors (IGF), IGF transport, and uptake, were upregulated in the VTM group. Additional pathways were identified using ShinyGO, which included the pancreatic secretion pathway, over-represented by genes such as PLCB1, CCK, and SLC26A3. The gene PLCB1 has been associated with feed efficiency, growth, and carcass traits in multiple species. Likewise, the SLC26A3 gene encodes a key intestinal chloride anion exchanger associated with enhanced feed efficiency in cattle. Genes encoding signaling molecules involved with immune response, T cell activation, and defense response were also among the DEGs upregulated in the VTM calves, including the TNFSF18 and TNFRSF4 genes. Our findings suggest that maternal prenatal vitamin and mineral supplementation throughout gestation affects the expression of genes involved in the jejunum function of offspring at a neonatal time point. The long-term consequences of these changes, however, warrant further investigation. [ABSTRACT FROM AUTHOR]

Vitamins and minerals have key roles in hormone production and action, enzyme activity, tissue synthesis, oxygen transport, and energy production. These micronutrients are efficiently transferred from the dam to the fetus during gestation to be partitioned for metabolic use and stored as postnatal mineral reserves. Maternal nutrient intake is one of the main factors that influence the availability of vitamins and minerals to the fetus. Thus, an inadequate supply of these critical nutrients can have a long-lasting impact on offspring growth and health. Evidence suggests that biological processes regulating normal growth, development, and nutrient utilization are programmed in utero, even during the earliest developmental stages. Therefore, there is a critical need to evaluate the effects of micronutrient supplementation during gestation on fetal physiology and metabolic programming. Our research group has developed research models examining the impact of maternal vitamin and mineral supplementation (VTM, supplemented vs. NoVTM, not supplemented) during the periconceptual period or throughout gestation in beef heifers. A metabolomic analysis revealed that metabolites in the oxidative phosphorylation pathway were more abundant in the liver of fetuses from VTM than NoVTM dams, suggesting that a greater supply of micronutrients during the periconceptual period and first trimester of pregnancy may positively modulate mitochondrial energy metabolism in offspring. These changes in the abundance of metabolites suggested physiological adaptations to meet fetal metabolic needs. Further, high-resolution respirometry analysis revealed greater efficiency of energy utilization in small intestinal samples of neonatal calves from VTM dams. In fact, VTM offspring were heavier from weaning to breeding phase than NoVTM offspring, suggesting that maternal nutrition affects physiological mechanisms in utero that modulate offspring energetics and efficiency of nutrient utilization in the postnatal period. Furthermore, we reported increased concentrations of histidine, aspartate, and 12 out of 14 neutral amino acids in the allantoic fluid of VTM-supplemented dams. Finally, genes involved with amino acid transport in fetal liver were upregulated in response to VTM supplementation, highlighting the intricate relationship between maternal and fetal nutrition. Vitamin and mineral supplementation were also associated with changes in gene expression, biological processes and pathways in placental tissue at d 83 of gestation. We observed an upregulation of genes in the calcium signaling and cyclic guanosine monophosphate (CGMP)-PKG signaling pathways in response to micronutrient supplementation. Calciummediated systems may modulate cell proliferation and steroidogenic activity in bovine placentomes, while CGMP-PKG plays a key role in vascular homeostasis. Placental blood vessel vascularity at term was indeed increased in heifers supplemented throughout gestation, emphasizing the importance of micronutrient supplementation beyond early pregnancy. Altogether, our findings suggest that vitamin and mineral supplementation in the periconceptual period and during gestation play a pivotal role in fetal metabolic programming with consequences extending to the postnatal period. [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]

Maternal nutrition in the periconceptional period influences gene regulation in the fetal liver across generations, affecting long-term metabolism. This study aimed to examine the effects of the rate of body weight (BW) gain of the dam (F0) during early gestation on the differential gene expression of the liver of first (F1) and second-generation (F2) offspring. Crossbred Angus heifers (F0) were assigned into two groups based on their targeted rate of BW gain during the first 84 d of gestation: low gain (LG; 0.28 kg/d; n = 8) or moderate gain (MG; 0.79 kg/d; n = 8). Following this period, all heifers (F0) were kept on a forage-based diet until the F1 offspring were weaned at 8 mo. The F1 heifers underwent estrus synchronization and were artificially inseminated at 15 mo of age. Liver samples were obtained from the F1 heifers at birth and later when harvested at 84 d of gestation, along with liver samples from their F2 fetuses, for a comprehensive multigenerational RNA-Seq analysis. Differentially expressed genes (DEGs) were identified using the DESeq2 R-package, focusing on significant genes determined by a P-value ≤ 0.05 and a log2 fold change |0.5|. Metabolic pathways and biological processes were analyzed using the WebGestalt tool to understand the implications of the observed gene expression changes. At birth, F1 heifers from MG dams exhibited 281 DEGs, comprising 152 downregulated and 129 upregulated genes compared with the offspring of LG dams. These genes were over-represented in lipid metabolism, cellular homeostasis, and signaling pathways, such as MAPK and chemokine signaling. At harvest, 159 DEGs were identified in F1 heifers, with 67 genes downregulated and 92 genes upregulated in the MG group. These genes were related to cellular morphogenesis and biogenesis processes, with a notable downregulation of metabolic pathways. For the F2 fetuses, 192 DEGs were identified, where 71 genes were downregulated, and 121 genes were upregulated. These genes were involved in biological functions such as peptide secretion to cell proliferation and signaling pathways, including PI3KAkt and Hippo signaling. The analysis of DEGs shared between F1 heifers and F2 fetuses highlighted the influence of the moderate BW weight gain of the F0 dams. At birth and harvest, F1 heifers shared three genes (NAV2, FAM131C, SH3D21). F1 heifers at birth and F2 fetuses shared five genes (CD3E, H1-12, SLC7A11, PIP4P2, ENSBTAG00000051730). From the harvest at d 84 in F1 heifers and F2 fetuses, five genes were shared (DCDC2, RIN1, ENSBTAG00000008911, ENSBTAG00000040518, ENSBTAG00000048049). No DEGs were shared across all comparisons. These findings emphasize the multigenerational impact of early gestational BW gain of the dam on liver gene expression, influencing metabolic pathways and signaling across generations. [ABSTRACT FROM AUTHOR]

Two experiments were conducted to evaluate the impacts of feeding a vitamin/mineral supplement to beef heifers throughout gestation on concentrations of immunoglobulin (Ig) in colostrum and in calf serum 24 h after consumption of maternal colostrum (Exp. 1) or a colostrum replacement product (Exp. 2). Angusbased beef heifers [n = 72, initial body weight (BW) = 380.4 ± 50.56 kg] were managed in an individual feeding system and randomly assigned to a basal diet targeting gain of 0.45 kg·heifer-1·d-1 (CON; n = 36) or the basal diet plus 113 g·heifer-1·d-1 of a vitamin/mineral supplement (VTM; n = 36). For Exp. 1 treatments began at the time of artificial insemination (AI) to sexed semen, and heifers becoming pregnant after first service AI (CON, n = 14; VTM, n = 17) continued treatments throughout gestation. At calving, heifer calves were allowed to nurse their dams and remained alongside their dams until weaning. For Exp 2. non-pregnant heifers were rebred 60 d after initial dietary treatments began and continued treatments throughout gestation, with resultant heifer calves (CON, n = 7; VTM, n = 7) being removed from their dams at birth and receiving 1.5 L of colostrum replacer containing 150 g globulin protein via an esophageal feeder, followed every 12 h by 1.9 L of milk replacer. In both experiments samples of colostrum were collected after completely milking the rear-right quarter of the udder. Blood samples were collected from calves before (within 2 h of birth) and 24 h after colostrum consumption. Concentrations of IgG, IgM, and IgA were quantified in colostrum and serum via bovine radial immunodiffusion plates. Data for both experiments were analyzed for the effect of treatment using the MIXED procedure in SAS, with additional analysis of data from Exp. 1 using the CORR procedure to determine correlations among dam colostrum and calf serum Ig concentrations at 24 h. In both experiments, maternal treatment did not affect (P = 0.21) concentrations of IgG, IgM, or IgA in colostrum at calving or in calf serum at 24 h. All calves from both experiments had undetectable concentrations of these respective immunoglobulins at birth. Concentrations of IgG at 24 h in calves that received maternal colostrum were 2,595.8 ± 535.38 mg/dL (Exp. 1), whereas those that received colostrum replacer were 1,610.6 ± 335.09 mg/dL (Exp. 2). Concentrations of IgG, IgM, and IgA were positively correlated (r = 0.34; P = 0.05) with concentrations of calf serum IgG, IgM, and IgA at 24 h after suckling. Our results suggest that maternal vitamin/mineral supplementation throughout gestation did not impact Ig concentrations in colostrum or the resultant serum Ig concentrations in calves either 24 h after suckling or after delivery of a commercial colostrum replacer. [ABSTRACT FROM AUTHOR]

During gestation, alterations in maternal nutrition during fetal development may alter growth trajectory and metabolic function in the developing fetus. Additionally, there is increasing evidence that the fetal microbiome also influences developmental outcomes. Research in this area is limited, and gastrointestinal microbiota has been the primary focus in cattle. Our objective was to assess the whole-body biogeography of the newborn calf microbiota and the response of these microbial communities and the calf immune system to prenatal vitamin and mineral (VTM) supplementation. Samples were collected from the hoof, liver, lung, nasal cavity, eye, rumen (tissue and fluid), and vagina of female beef calves that were born from dams that received either prenatal VTM or no VTM (Control; n = 7/group) throughout gestation. Calves were separated from their dams immediately after birth and fed colostrum replacement until euthanasia at 30 h post-initial colostrum feeding. The microbiota from swab and tissue samples were assessed using 16S rRNA gene sequencing (V4) and qPCR. Serum samples were processed for multiplex quantification of 15 cytokines and chemokines. Sequencing revealed the presence of a relatively diverse and complex microbiota in each of the 7 anatomical locations. The community structure of the hoof, liver, ocular, and vaginal microbiota were significantly different from the ruminal microbiota (0.64 = R2 = 0.12, P = 0.003). The respiratory. (nasal and lung) had similar community structures to that of ocular, vaginal, and ruminal fluid microbiota (P > 0.11). The ocular, hoof, and vagina had the greatest microbial richness (observed ASVs; P < 0.05) but similar diversity (Shannon; P > 0.05) compared with other samples. The liver and ruminal fluid had the least microbially rich communities, the latter also being the least diverse (P < 0.05). Firmicutes, Actinobacteriota, and Proteobacteria were the dominant phyla across all sample types, but their abundance varied by location. The ruminal fluid and hoof had the greatest bacterial concentration, while the liver, lung and ruminal tissue had reduced bacterial abundance as estimated by qPCR. An influence of VTM supplementation on microbial community structure was only detected in the ruminal fluid microbiota (P < 0.01). While prenatal VTM supplementation did not affect the nasal, lung, liver, and hoof microbiota, differences (P < 0.05) were detected in microbial richness (vagina), diversity (ruminal tissue and fluid, ocular), composition at the phylum level (ruminal tissue, ocular, and vagina), and total bacterial abundance (ocular and vagina). Among the 15 cytokines evaluated, the concentration of IP-10 was increased (P = 0.02) while IL-4 and IL-17A were reduced (P < 0.05). [ABSTRACT FROM AUTHOR]

Emerging evidence suggests that urogenital microbiome-targeted approaches may provide a novel opportunity to reduce the incidence of reproductive failures in cattle. The objectives of this study were to: 1) characterize the vaginal and uterine microbiota between beef cattle that became pregnant via artificial insemination (AI) and those that did not; 2) identify differentially abundant taxa between pregnant and non-pregnant cattle; and 3) characterize the culturable fraction of the vaginal and uterine microbiota using extensive culturing. Vaginal and uterine swab samples were collected from two cohorts of Angus-crossbred cattle: mature cows (n =100) and heifers (n = 72, vaginal swab only) at the time of AI. At 35 days post-AI, pregnancy diagnoses were made via ultrasound. A subset of vaginal and uterine swabs from cows (27 non-pregnant and 31 pregnant) and heifers (26 non-pregnant and 33 pregnant) were selected and processed for microbiota assessment using 16S rRNA gene (V3-V4) sequencing. For culturing, a subset of cryopreserved vaginal and uterine swabs (128) were plated onto three different agar types and cultured, and isolates were identified by nearfull length 16S rRNA gene sequencing. Sequencing results revealed 11 taxa that were more abundant in the vaginas of heifers that failed to become pregnant via AI than heifers that did become pregnant. While there was no significant difference in vaginal microbiota community structure (P = 0.21) between pregnant and non-pregnant cows, non-pregnant cows tended to have greater microbial richness and Shannon diversity (P ≤ 0.08) compared with pregnant cows. No differentially abundant taxa were detected in the vaginas of pregnant versus non-pregnant cows. Pregnant cows had a distinct uterine microbiota community structure (R² = 0.032, P = 0.008) but similar alpha diversity (P > 0.1) compared with non-pregnant cows. Twenty-eight differentially abundant taxa were observed in the uterine microbiota between pregnant and non-pregnant groups, with 11 of them more abundant in pregnant cows. Methanobrevibacter ruminantium (archaea) and Fusobacterium necrophorum were among these 11 positive pregnancy-associated taxa. Although community structure was significantly different between the vagina and uterus, 277 "core taxa" (present in = 80% of all samples) were shared between the two communities. A total of 733 bacterial isolates were recovered from vaginal (512) and uterine (221) swabs under aerobic (n = 363, 83 different species) and anaerobic (n = 370, 69 species) culturing. Potential pathogenic isolates within the Trueperella, Mannheimia and Histophilus genera were most exclusively identified from vaginal swabs. Only two Lactobacillus isolates were recovered. Overall, our results indicate that pregnancy-associated taxonomic signatures are present in the bovine uterine and vaginal microbiota. Among 39 pregnancy statusassociated taxa, 41% were unclassified at the genus level, suggesting that shotgun metagenomics and culturomics are needed to identify and characterize the pregnancy-associated taxa in cattle. [ABSTRACT FROM AUTHOR]

Objectives were to evaluate the effects of feeding a vitamin and mineral (VTM) supplement to beef heifers during gestation on calf performance, body measurements, trace mineral status, and organ weights at 30 h after birth. We hypothesized that VTM supplementation during gestation would improve mineral status in the neonatal calf but not impact calf performance parameters and body and organ weights at 30 hours after birth. Fourteen Angus-based heifers [initial body weight (BW)] = 273.7 ± 1.10 kg) were randomly assigned to receive either a basal diet (CON; n = 7) or a basal diet plus a VTM supplement (VTM; n = 7; 113 g•heifer-1•d-1, targeting gain of 0.45 kg/day) from 60 d pre-breeding through gestation. Immediately after parturition, blood samples were collected from dams and calves, then calves were separated from their dams. Calves were fed one feeding of colostrum replacer, followed by milk replacer every 12 h, then euthanized at 30 h. Body weight and measurements were recorded, then organs and viscera were removed, weighed, and sampled. Dam serum and neonatal serum, liver, and blood were analyzed for concentrations of minerals. Data were analyzed using the GLM Procedure of SAS with individual animal as the experimental unit. Dietary treatments did not impact calf weight (0 h or 30 h), calf body measurements, or body weight of the dam at calving (P ≥ 0.32). Further, neonatal organ weights were not influenced (P ≥ 0.21) by maternal VTM treatment. Concentrations of Se and Co in calf serum and Se in calf liver were increased (P ≤ 0.02) by VTM treatment; however, concentrations of Cu, Mn, Mo, and Zn in calf muscle, liver, and serum were not impacted (P ≥ 0.07) by VTM treatment. Concentrations of Co in serum of the dam was the only mineral affected by dietary treatments, being greater (P = 0.001) in VTM than CON dams. In the current experiment providing trace mineral supplementation throughout gestation did not impact calf weight or body measurements at birth. However, the implications of altered mineral status of the neonatal calves at birth, and presumably throughout gestation, may have additional postnatal effects that warrant further investigation. [ABSTRACT FROM AUTHOR]