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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]

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]

Objectives of this experiment were to characterize the effects of ram plane of nutrition on body composition, concentrations of hormones and metabolites, sperm characteristics, and offspring outcomes. Mature Rambouillet rams (n  = 24, BW = 82.9 ± 2.63 kg) were individually housed and randomly assigned to either a positive (POS ; n  = 8), maintenance (MAINT ; n  = 8), or negative (NEG ; n  = 8) plane of nutrition for an 84-day feeding period. Rams were fed a common diet, with daily feed allocations adjusted weekly based on body weight (BW) to achieve the targeted weight gain or loss (approximately 12% of initial BW). On 0, 28, 56, and 84-d, body condition score (BCS) and scrotal circumference (SC) were recorded, and blood and semen were collected. Following the feeding period, rams were placed in pens with 10 ewes each for a 28-d breeding period. Ewes were managed similarly throughout gestation and body weight and measurements were recorded at birth and weaning. Data were analyzed as repeated measures in time where appropriate with the mixed procedure of SAS, and individual ram was the experimental unit for all analysis. Ram BW was influenced by a treatment × day interaction (P  < 0.001), with POS (0.12 ± 0.01 kg) having greater daily weight change than MAINT (0.1 ± 0.01 kg), which was greater than NEG (-0.12 ± 0.01 kg). Ram BCS and SC were influenced by treatment × day interactions (P  ≤ 0.01), being similar on day 0 but POS being greater than NEG by day 56. Concentrations of triiodothyronine (T3) and T3:T4 ratio exhibited treatment × day interactions (P  ≤ 0.02), as POS had greater values than NEG by day 84 (P  ≤ 0.02). Concentration of insulin-like growth factor-1 was greater in POS than MAINT and NEG (P  ≤ 0.02), and non-esterified fatty acids and thyroxine (T4) were influenced by a day effect (P  ≤ 0.01), but testosterone was unaffected (P  ≥ 0.09). Minimal differences in semen volume, sperm concentration, motility, or morphology were observed among treatments (P  ≥ 0.31). A similar proportion of ewes bred by rams in the respective treatments lambed and weaned lambs (P  ≥ 0.54). Birth weight, chest circumference, and shoulder-hip length were greater (P  ≤ 0.05) in NEG lambs compared with POS and MAINT; however, no differences were detected in weaning weight and weaning body measurements (P ≥ 0.40). Findings suggest paternal nutrition during the period of sperm development may influence offspring outcomes, potentially as a result of in-utero programming of paternal origin. [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]