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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 (T3), thyroxine (T4), 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 T4were 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.Undernutrition in mature rams prior to conception impaired insulin secretion and altered hormone concentrations in female offspring in a growing state. In addition, overnutrition in sires influenced the growth of female offspring, particularly when managed at an accelerated rate of gain. Thus, our results suggest that nutritional management of sires prior to breeding can impact offspring metabolism and endocrine profiles postnatally.Recent literature suggests that exposure of the sire to excess or inadequate nutrition before breeding could contribute to altered growth, metabolism, and reproduction of their offspring. Exposure of the offspring to postnatal environmental stressors may further exacerbate the effects of sire nutrition on growth and metabolism. Utilizing a divergent plane of nutrition model in mature rams, our results demonstrated that female offspring exhibited differences in growth and glucose metabolism based on paternal nutritional status. Overnutrition in sires influenced growth in female offspring, particularly when ewes were managed at a greater rate of gain. Additionally, a glucose tolerance test following a period of weight gain revealed that insulin secretion was impaired in ewe lambs sired by undernourished rams. Minimal differences in ovarian characteristics and ovarian reserve were observed in offspring for either sire or ewe lamb dietary treatments, but the potential for epigenetic modifications to the gametes remains to be explored. These findings suggest a role of prebreeding paternal nutrition in the metabolic programming of their female offspring during in utero development.

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 PPARGgenes 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.Moderate maternal body weight gain during early gestation in beef heifers improved pre-breeding body weight and concentrations of blood glucose in F1 offspring during early gestation. Maternal rate of gain impacted intestinal gene expression and placental and mammary gland mass in the F2 offspring.Early gestation is a period of rapid development of the placenta and fetal organs. In some species, impacts of nutrition during gestation persist across generations. Thus, adequate nutrition is crucial for the offspring’s future productivity and reproductive success. This study aimed to assess the impact of 2 rates of body weight gain (0.20 and 0.75 kg/d) in F0 dams during early gestation on the productive and reproductive outcomes of F1 progeny and the development of F2 fetuses. The results indicate that a moderate rate of body weight gain during early gestation did not affect the development of ovarian follicles in F1 offspring but increased the body weight of F1 heifers in the pre-breeding period and concentrations of blood glucose during gestation. There were tendencies of F0 nutrition to impact placental weight, F2 mammary gland weight, and intestinal mRNA relative abundance, which could have implications on nutrient supply to the developing fetus and on future lactation and metabolism. These findings highlight the complexity of multigenerational interactions in the context of maternal nutrition and provide valuable insights to optimize productivity and reproductive performance in livestock systems.Graphical Abstract

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:T4ratio 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.Alterations to ram nutrition before the breeding season change their body composition and hormone concentrations, but not semen characteristics or reproductive performance when mated to ewes. However, differences in lamb birth weights and body measurements suggest paternal programming affects on offspring are elicited as a result of ram nutrition during spermatogenesis.This study was conducted to evaluate whether ram nutrition during the spermatogenesis impacts their body composition, concentrations of circulating hormones and metabolites, semen characteristics, fertility, and subsequent offspring growth and development. Rams were managed on treatments to gain, lose, or maintain body weight over an 84-day period. The changes in ram body weight that were imposed by our treatments resulted in changes in body condition score, scrotal circumference, and concentrations of several metabolic hormones, including thyroid hormones and insulin-like growth factor-1. However, no differences in sperm concentration or motility were observed. After the 84-d feeding period, rams were placed with ewes for a 28-d breeding period and ewes were monitored throughout gestation, lambing, and until weaning of the resulting lambs. Although no differences in ewe pregnancy rates were observed after the breeding period, lamb birth weight and body measurements were greater in rams that lost weight during spermatogenesis. Thereafter, body weight and growth performance of offspring were similar among sire treatments, but continued evaluation of offspring throughout the postnatal period is necessary. These findings indicate that paternal nutrition during spermatogenesis can impact offspring outcomes, potentially through epigenetic alterations to the sperm and subsequent in-utero programming of paternal origin.

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.A moderate rate of maternal body weight (BW) gain in beef heifers for the first 84 d of gestation altered body composition and concentrations of hormones and metabolites throughout gestation. Consequently, this led to greater BWs and measurements of F1 heifer calves at birth compared with cohorts from dams managed at a low rate of BW gain. Daily gain and feed efficiency were greater during a development period for F1 heifers exposed to enhanced gain in utero, indicating a postnatal developmental programming response elicited by maternal nutrition during early gestation.Generally, beef heifers are managed on grazing pastures during early gestation, which are subject to fluctuations in forage quantity and quality. Variations in the nutrients available to the dam can impact the developing offspring during early gestation. Providing energy/protein supplements to grazing cattle is a method to ensure nutrient requirements are being met and to enhance the rate of gain. This study modeled the effects of pasture supplementation in beef heifers during early gestation to determine whether 2 rates of body weight (BW) gain alter maternal body composition and concentrations of hormones and metabolites, as well as changes to postnatal characteristics of the subsequent F1 generation heifer calves. The rate of gain affected the heifer’s BW, body composition, and concentrations of key metabolites and hormones, which likely altered the nutritional environment experienced by the fetus. Subsequently, F1 offspring from supplemented dams had greater morphometric characteristics at birth and had greater BW gain, feed efficiency, and eating rate during the postweaning development period. However, body composition, concentrations of hormones and metabolites, other feeding behaviors, puberty attainment, and response to vaccination of offspring were not affected. Further research is warranted to investigate how the early gestational rate of BW gain impacts key metabolic organs and mechanisms involved in transferring programming outcomes to subsequent generations.

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.Vitamin and mineral supplementation to beef heifers throughout gestation resulted in greater concentrations of Co, Se, and vitamin D in the blood of offspring at birth. Neonatal calves were harvested 30 h after birth and no differences were observed in BW, organ weight, or ovarian reserve.Vitamins and minerals are essential for the reproduction, performance, skeletal support, and overall health of beef cattle. During pregnancy, vitamins and minerals are critical for proper fetal growth, development, and establishment of postnatal micronutrient reserves. The study objectives were to evaluate the impacts of vitamin and mineral supplementation to beef heifers throughout gestation on female offspring morphometric characteristics at birth, mineral status and blood metabolite/endocrine profiles of the dam and calf, histological evaluation of calf ovaries, and organ weights of the neonate at 30 h of age. We hypothesized that vitamin and mineral supplementation to the dam during pregnancy would increase calf size and organ masses, mineral status, and blood metabolite and hormone profiles. We observed no differences in calf body measurements, organ masses, and offspring ovarian reserve between calves from supplemented and nonsupplemented dams. However, Co, Se, and vitamin D status was increased in the supplemented dam and calf, and we propose that enhanced vitamin and mineral status at birth may support the underdeveloped immune system, growth performance, and overall health of the neonate in the postnatal period. Further research is warranted to investigate postnatal offspring health, performance, and efficiency of energy utilization in key metabolic tissues in the calf.