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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]

Herein, we evaluated the hepatic lipid metabolic profiles of bovine fetuses in response to maternal vitamin and mineral supplementation (VMSUP; supplemented (VTM) or not (NoVTM)) and two different rates of gain (GAIN; low gain (LG), 0.28 kg/d, or moderate gain (MG), 0.79 kg/d). Crossbred Angus heifers (n = 35; initial BW = 359.5 ± 7.1 kg) were randomly assigned to a 2 × 2 factorial arrangement, resulting in the following treatment combinations: NoVTM-LG (n = 9), NoVTM-MG (n = 9), VTM-LG (n = 9), and VTM-MG (n = 8). Heifers received their treatments until d 83 of gestation, when they were ovariohysterectomized. Fetuses were harvested and liver samples were analyzed via ultrahigh-performance liquid chromatography–tandem mass spectroscopy to characterize lipid profiles and abundances. We identified 374 biochemicals/metabolites belonging to 57 sub-pathways of the lipid metabolism super-pathway. The majority of the biochemicals/metabolites (n = 152) were significantly affected by the main effect of GAIN. Maternal moderate rates of gain resulted in greater abundances (p ≤ 0.0001) of ω-3 fatty acids (eicosapentaenoate, docosapentaenoate, and docosahexaenoate) and lower abundances (p ≤ 0.0001) of ω-6 fatty acids. Further, MG resulted in the accumulation of several diacylglycerols and depletion of the majority of the monoacylglycerols. Concentrations of nearly all acylcarnitines (p ≤ 0.03) were decreased in VTM-LG fetal livers compared to all other treatment combinations, indicating a greater rate of complete oxidation of fatty acids. Levels of secondary bile acids were impacted by VMSUP, being greater (p ≤ 0.0048) in NoVTM than in VTM fetal livers. Moreover, NoVTM combined with lower rate of gain resulted in greater concentrations of most secondary bile acid biochemicals/metabolites. These data indicate that maternal diet influenced and altered fetal hepatic lipid composition in the first trimester of gestation. Maternal body weight gain exerted a greater influence on fetal lipid profiles than vitamin and mineral supplementation. Specifically, lower rate of gain (0.28 kg/d) resulted in an increased abundance of the majority of the biochemicals/metabolites identified in this study. [ABSTRACT FROM AUTHOR]

We hypothesized that maternal nutrition during the first 50 d of gestation would influence the abundance of hexose transporters, SLC2A1, SLC2A3, and SLC2A5, and cationic amino acid transporters, SLC7A1 and SLC7A2, in heifer uteroplacental tissues. Angus-cross heifers (n = 43) were estrus synchronized, bred via artificial insemination, and assigned at breeding to 1 of 2 dietary intake groups (CON = 100% of requirements to achieve 0.45 kg/d of BW gain or RES = 60% of CON intake) and ovariohysterectomized on day 16, 34, or 50 of gestation (n = 6 to 9/d) in a completely randomized design with a 2 × 3 factorial arrangement of treatments. Uterine cross-sections were collected from the horn ipsilateral to the corpus luteum, fixed in 10% neutral buffered formalin, sectioned at 5 µm, and stained via immunofluorescence for transporters. For each image, areas of fetal membrane (FM ; chorioallantois), luminal epithelium (ENDO), superficial glands (SG), deep glands (DG), and myometrium (MYO) were analyzed separately for relative intensity of fluorescence as an indicator of transporter abundance. Analysis of FM was only conducted for days 34 and 50. No transporters in target areas were influenced by a day × treatment interaction (P ≥ 0.06). In ENDO, all transporters were differentially abundant from days 16 to 50 of gestation (P ≤ 0.04), and SLC7A2 was greater (P = 0.05) for RES vs. CON. In SG, SLC7A1 and SLC7A2 were greater (P ≤ 0.04) at day 34 vs. day 16. In DG, SLC2A3 and SLC7A1 were greater (P ≤ 0.05) for CON vs. RES heifers; furthermore, SLC7A1 was greater (P < 0.01) at day 50 vs. days 16 and 34 of gestation. In MYO, SLC7A1 was greater (P < 0.01) for CON vs. RES and was greater (P = 0.02) at days 34 and 50 vs. day 16. There were no differences in FM (P ≥ 0.06). Analysis of all uterine tissues at day 16 determined that SLC2A1, SLC2A3, and SLC7A2 were all differentially abundant across uterine tissue type (P < 0.01), and SLC7A1 was greater (P = 0.02) for CON vs. RES. Analysis of all uteroplacental tissues at days 34 and 50 demonstrated that all transporters differed (P < 0.01) across uteroplacental tissues, and SLC7A1 was greater (P < 0.01) for CON vs. RES. These data are interpreted to imply that transporters are differentially affected by day of gestation, and that hexose and cationic amino acid transporters are differentially abundant across utero-placental tissue types, and that SLC7A1 is responsive to maternal nutritional treatment. [ABSTRACT FROM AUTHOR]

To determine the effects of maternal supplementation on the mRNA abundance of genes associated with metabolic function in fetal muscle and liver, pregnant sows (Landrace × Yorkshire; initial body weight (BW) 221.58 ± 33.26 kg; n = 21) fed a complete gestation diet (corn–soybean meal based diet, CSM) were randomly assigned to 1 of 4 isocaloric supplementation treatments: control (CON , 378 g/d CSM, n = 5), sucrose (SUGAR , 255 g/d crystalized sugar, n = 5), cooked ground beef (BEEF , 330 g/d n = 6), or BEEF + SUGAR (B+S , 165 g/d cooked ground beef and 129 g/d crystalized sugar, n = 5), from days 40 to 110 of gestation. Sows were euthanized on day 111 of gestation. Two male and 2 female fetuses of median BW were selected from each litter, and samples of the longissimus dorsi muscle and liver were collected. Relative transcript level was quantified via qPCR with HPRT1 as the reference gene for both muscle and liver samples. The following genes were selected and analyzed in the muscle: IGF1R , IGF2 , IGF2R , GYS-1 , IRS-1 , INSR , SREBP-1C , and LEPR ; while the following were analyzed in the liver: IGF2 , IGF2R , FBFase , G6PC , PC , PCK1 , FGF21 , and LIPC. No effect of fetal sex by maternal treatment interaction was observed in mRNA abundance of any of the genes evaluated (P > 0.11). In muscle, the maternal nutritional treatment influenced (P = 0.02) IGF2 mRNA abundance, with B+S and SUGAR fetuses having lower abundance than CON, which was not different from BEEF. Additionally, SREBP-1 mRNA abundance was greater (P < 0.01) for B+S compared with CON, BEEF, or SUGAR fetuses; and females tended (P = 0.06) to have an increased abundance of SREBP-1 than males. In fetal liver, IGF2R mRNA abundance was greater (P = 0.01) for CON and BEEF than SUGAR and B+S; while FBPase mRNA abundance was greater (P = 0.03) for B+S compared with the other groups. In addition, maternal nutritional tended (P = 0.06) to influence LIPC mRNA abundance, with increased abundance in CON compared with SUGAR and B+S. These data indicate limited changes in transcript abundance due to substitution of supplemental sugar by ground beef during mid to late gestation. However, the differential expression of FBPase and SREBP-1c in response to the simultaneous supplementation of sucrose and ground beef warrants further investigations, since these genes may play important roles in determining the offspring susceptibility to metabolic diseases. [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]

Thirty-five crossbred Angus heifers (body weight = 359.5 >± 7.1 kg) were randomly assigned to a 2 × 2 factorial design to evaluate the effects of vitamin and mineral supplementation [VMSUP; supplemented (VTM) vs. unsupplemented (NoVTM)] and rate of gain [GAIN; low gain (LG), 0.28 kg/d vs. moderate gain (MG), 0.79 kg/d] during the first 83 d of gestation on trace mineral concentrations in fetal liver, muscle, and allantoic (ALF) and amniotic (AMF) fluids. The VTM treatment (113 g supplement•heifer-1•d-1) was initiated a minimum 71 d before breeding. At breeding, heifers were either maintained on the basal diet (LG) or received the MG diet by adding a protein/energy supplement to the basal diet. On d 83 of gestation, samples of fetal liver, muscle, ALF, and AMF were collected and analyzed for trace mineral concentrations. In fetal liver, Se, Cu, Mn, and Co concentrations were greater (P ≤ 0.04) for VTM than NoVTM, while Mo and Co greater (P ≤ 0.04) for LG than MG. In fetal muscle, VTM increased (P ≤ 0.02) concentrations of Se and Zn, whereas LG increased (P < 0.01) Zn. In ALF, Mo concentrations were affected (P = 0.03) by a VMSUP × GAIN interaction, with VTM-MG greater than NoVTM-MG; while VTM increased (P < 0.01) concentrations of Se and Co. Trace mineral concentrations were not affected (P ≥ 0.13) in AMF. In conclusion, VTM increased fetal liver Se, Cu, Mn, and Co concentrations; fetal muscle Se and Zn; and ALF Se and Co; while LG increased fetal liver Mo and Co concentrations and fetal muscle Zn. Our results confirm that managerial decisions associated with vitamin and mineral supplementation and rate of gain can alter fetal reserves of trace elements during early pregnancy. [ABSTRACT FROM AUTHOR]

In the present study, we evaluated whether the nasopharyngeal, ruminal, and vaginal microbiota would diverge (1) in virgin yearling beef heifers (9 months old) due to the maternal restricted gain during the first trimester of gestation; and (2) in pregnant beef heifers in response to the vitamin and mineral (VTM) supplementation during the first 6 months of pregnancy. As a secondary objective, using the microbiota data obtained from these two cohorts of beef heifers managed at the same location and sampled at the same time, we performed a holistic assessment of the microbial ecology residing within the respiratory, gastrointestinal, and reproductive tract of cattle. Our 16S rRNA gene sequencing results revealed that both α and β-diversity of the nasopharyngeal, ruminal and vaginal microbiota did not differ between virgin heifers raised from dams exposed to either a low gain (targeted average daily gain of 0.28 kg/d, n = 22) or a moderate gain treatment (0.79 kg/d, n = 23) during the first 84 days of gestation. Only in the vaginal microbiota were there relatively abundant genera that were affected by maternal rate of gain during early gestation. Whilst there was no significant difference in community structure and diversity in any of the three microbiota between pregnant heifers received no VTM (n = 15) and VTM supplemented (n = 17) diets, the VTM supplementation resulted in subtle compositional alterations in the nasopharyngeal and ruminal microbiota. Although the nasopharyngeal, ruminal, and vaginal microbiota were clearly distinct, a total of 41 OTUs, including methanogenic archaea, were identified as core taxa shared across the respiratory, gastrointestinal, and reproductive tracts of both virgin and pregnant heifers. [ABSTRACT FROM AUTHOR]

We evaluated effects of rate of gain during the first 84 d of gestation on composition of colostrum and milk. At breeding, forty-five Angus-based heifers received either a basal total mixed ration allowing 0.28 kg/d gain [low gain (LG), n = 23] or basal diet plus starchbased supplement allowing 0.79 kg/d gain [moderate gain (MG), n = 22] for 84 days. Heifers were then managed on a common diet until parturition. Colostrum samples (50 mL) were collected before first suckling. Milk samples (50 mL) were collected 6 hours after calf removal on d 62 ± 10 and 103 ± 10 postpartum. Samples were collected by stripping each teat 15 to 20 times after discarding the first 5 strips. At d 103 sampling techniques were compared by collecting a second sample after 1 mL oxytocin administration and 90 sec lag. Data were analyzed using the GLM procedure of SAS. Fat, protein, somatic cell count (SCC), milk urea nitrogen, and other solids were analyzed in colostrum for effect of treatment, whereas milk was evaluated for effects of treatment, day and their interaction. Heifer was experimental unit and significance was set at P ≤ 0.05. Colostrum SCC was greater (P = 0.05) in LG (6,949 ± 739 cells/mL) than MG (4,776 ± 796 cells/mL). In milk, protein and other solids were greater (P ≤ 0.03) in MG (3.02 ± 0.03 and 6.20 ± 0.02 %, respectively) than LG (2.87 ± 0.03 and 6.14 ± 0.02 %, respectively). On d 103, oxytocin administration and extended lag time after teat stimulation (0.96 ± 0.05 %) increased fat content in milk (P < 0.01) compared with immediate milk sample collection (0.34 ± 0.05 %). Nutrition during early gestation had a sustained impact on milk composition and techniques of oxytocin administration results in greater milk fat content. [ABSTRACT FROM AUTHOR]