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ObjectivesTo determine the influence of corn supplementation of beef cows during winter and their impact on offspring beef quality attributes.Materials and MethodsForty-seven multiparous Angus beef cows carrying male calves were assigned randomly to two dietary treatments: corn supplementation at 0.2% BW (SUP; n = 24) vs. non-supplementation (NSUP; n = 23) at d 110 d of gestation for 22 wks. Ad-libitum access to low-quality forage was provided to both groups. At 7 d post-calving, a muscle biopsy was collected from the longissimus dorsi muscle (LD) of each calf for muscle fiber typing. Offspring were managed as a single group from nursing through to the backgrounding phase. Thereafter, the steers were placed in the feedlot and assigned to 4 pens (blocks) based on BW and offered ad-libitum access to a 100% corn silage-based ration (76.97% TDN, 11.07% CP), salt and minerals. When the steers reached a final BW of 615 kg (∼16 mo of age), they were slaughtered in a commercial abattoir. A second LD muscle biopsy sample was obtained at 45 min postmortem (PM) for muscle fiber typing. At 96 h PM, striploins (n = 42) were collected, aged for 14 d and samples obtained for Warner Bratzler shear force (WBSF), proximal composition, myofibril fragmentation index (MFI), collagen analysis and objective color evaluation. Data were analyzed as a randomized block design.ResultsImmunofluorescent analysis for the myosin heavy chain (MHC) isoform on the proportion of the fiber type or fiber dimensions was not influenced by maternal dietary treatment at both ages (P > 0.05). However, regardless of maternal dietary treatment, the proportion of fiber type IIA decreased while type IIAX increased in samples from steers at 16 mo of age compared with samples from steers at 7 d of age. No differences were observed between dietary treatment groups in proximate composition (P = 0.8), MFI (P = 0.29), or collagen content (P 0.98); however, WBSF values tended to be higher in steers from SUP cows than steers from NSUP dams (P = 0.07). Maternal dietary treatment had no influence on objective color evaluation at the retail display (P > 0.05). Objectives traits were not affected by dietary treatment × display time interaction (P = 0.92).ConclusionOur findings indicate that corn supplementation of cows during mid to late gestation has minimal effects on muscle fiber type and beef quality of their offspring. Thus, corn supplementation of low-quality forage offered during mid to late gestation did not have detrimental effects on muscle fibers and meat quality of offspring.

ObjectivesThe objectives of this study were to investigate the influence of substituting supplemental sucrose with beef on maternal health and fetal development using a sow biomedical model.Materials and MethodsMultiparous crossbred sows (BW = 222 kg; n = 21; rep = 3) were individually housed from d 30 to 111 (± 0.58) of gestation. From d 30 to 39, a complete sow ration (corn-soybean meal-based, CSM) was fed at 1% of d 30 gestational BW. On d 39, daily dietary ration was adjusted to 1% of d 39 gestational BW which was fed daily at 0700 h from d 40 to 110 (± 0.58). Sows were randomly assigned to 1 of 4 isocaloric supplement treatments; 126 g CSM to serve as a control (CON, n = 5), 110 g cooked ground beef (BEEF, n = 6), 85.5 g sucrose (SUCR, n = 5), or 54.8 g BEEF and 42.7 g SUCR (B+S, n = 5). Dietary supplements were fed daily at 1100, 1500, and 1800 h from d 40 to 110 (± 0.58). Blood was collected via jugular venipuncture from sows on d 29 and 111 (± 0.58). Blood chemistry was immediately analyzed, and serum samples were collected for lipid panel and insulin concentrations. Bodyweights were measured on d 30, 39, 54, 68, 82, 96, and 111 (± 0.58). Tenth rib and last rib SQ fat depth were measured on d 35, 70, and 110 (± 0.58) via ultrasound. Sows were euthanized on d 111 (± 0.58). Reproductive tract (RT), pancreas, kidney, liver, heart, heart fat, lung, semimembranosus and abductor (SM), and semitendinosus (ST) weights were collected and recorded from each sow. Two median weight male and female fetuses were selected from each sow for tissue collections. Fetal tissue collection was the same as sows with the addition of testes and no RT weight. A repeated measures design, with sow as the repeated measure, was modeled using the MIXED procedure of SAS using compound symmetry variance covariance matrix. Sow data fixed effects were replicate, sow, and treatment. Fetal data fixed effects were replicate and fetal weight category. Covariates were determined for each individual trait depending on goodness of fit. A treatment by day interaction was used for sow data while a treatment by sex interaction was used for fetal data. Alpha level was 0.05.ResultsDietary treatment did not influence gestational BW (P ≥ 0.99), SQ fat depth (P ≥ 0.09), blood chemistry (P ≥ 0.21), or serum concentrations (P ≥ 0.07). Dietary treatment did not influence sow tissue weight (P ≥ 0.42). Compared with CON, BEEF fetuses had greater fetal BW (P = 0.01), crown to rump length (P = 0.01), nose to crown length (P < 0.01), heart girth (P = 0.02), and abdominal girth (P = 0.05). Dietary treatment did not influence fetal growth characteristics of median weight male and female fetuses (P ≥ 0.23). Compared with BEEF, SUCR fetuses had heavier liver weights (31.43 ± 2.06 and 40.13 ± 2.09, respectively; P = 0.04). There was a dietary treatment by sex interaction for fetal kidney weight with BEEF males having lighter kidney weights compared with all other interactions (P = 0.03). Dietary treatment did not influence any other fetal tissue weight (P ≥ 0.09).ConclusionBeef and/or sucrose supplementation during mid-to-late gestation has minimal effects on swine maternal health and fetal development. Differences in fetal liver and kidney weights should be examined further. Further research is needed to determine the effect of gestational supplementation on human health and development.