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Maternal gestational nutrition is known to impact gut physiology and the gut microbiome of offspring early in life; however, it remains unknown if these changes persist later in life. We hypothesized that the impacts of maternal feed restriction in late gestating beef cows on early colonization of the calf gut would impact the rumen microbiome post-weaning. Our objective was to compare the post-weaning rumen microbiome of calves born with feed restricted dams and those born to dams with adequate nutrition. Starting roughly 60 d before expected calving, dams were stratified to either receive 100% of NRC requirements (CON) or 70% intake of NRC requirements (FR) through 28 d post-parturition. Pairs were then moved on to native grass until weaning. Rumen fluid was collected from the calves at the time of weaning (PRE) and after a 70 d backgrounding feed efficiency study (POST). Microbial DNA was isolated and the V4 region of the 16S rRNA was sequenced on the MiSeq platform. Data were analyzed within each time point using QIIME2. Maternal treatment had no impact on alpha diversity (Faith's phylogeny, Shannon's diversity, and Evenness) in the PRE group, but CON calves had greater (q = 0.05) evenness than FR calves in the POST samples. There were differences in composition between CON and FR in the PRE samples (unweighted unifrac q = 0.04; bray-curtis q = 0.03). No differences (q = 0.14) in composition were found in the POST samples. These data indicate that at the time of weaning (PRE) differences in composition existed in CON vs. FR calves, specifically in the rare taxa, but the microbial composition converged by the end of the feeding trial. Interestingly, previous findings in our lab reported differences in alpha and beta diversity 28 d after birth in these calves. Together, these data indicate the potential for long-term impacts of maternal nutrition on the gut microbiome. This coupled with the previously published work where feed efficiency tended to differ between CON and FR, suggests that early perturbations during gestation may have had lasting impacts on gut physiology and subsequent performance in the presence of rumen microbial shifts. [ABSTRACT FROM AUTHOR]

Late feedlot death caused by congestive heart failure has been quantified extensively through epidemiological studies however, these models do not consider losses or gains associated live growth performance, carcass quality, and consumer rejection of meat products. To address these gaps in the literature, we conducted two studies to characterize effects of pulmonary hypertension on four populations of feedlot cattle. In study one, reproductively intact (INT, n = 19), and ovariectomized (OVX, n = 18) yearling Sim-Angus heifers were selected on heart failure risk according to their pulmonary arterial pressure. Heifers were gradually transitioned onto a feedlot ration and fed to an acceptable harvest body composition determined using both 12th rib subcutaneous fat and body weight. Cattle were weighed biweekly and ADG was calculated by regressing body weight by days on feed (DOF). Pulmonary arterial pressure (PAP) was measured approximately every 3 months by a qualified veterinarian. Cattle were harvested at a commercial harvesting facility where carcass data and muscle samples were collected. In study two, weaned sim-angus steers (n = 41) were selected on heart failure risk categories using the same methodology outline above. Twenty steers were administered a steroidal growth promoting implant upon receiving (IMP) and twenty were untreated (NAT). Steers were fed to an average of 610 kg and data were collected using the same methodology outlined above. Data were analyzed using ANOVA, linear model, and Pearson correlation functions in R statistical software where PAP was used as a fixed continuous variable. Data were analyzed by study with the exception of live growth performance regression and correlations where data were combined. Linear regression within the combined datasets showed that initial mean PAP (P < 0.001), diastolic pressure (P < 0.001), and sex (P < 0.001) positively influenced ADG throughout the duration of the finishing period. Furthermore, initial PAP was moderately correlated with ADG (R = 0.38, P < 0.001). Gain to feed (G:F) was positively correlated with initial diastolic PAP (R = 0.31, P < 0.006). Neither initial mean PAP nor diastolic pressures impacted dry matter intake (DMI; P > 0.90), but sex was associated with DMI where steers had significantly decreased DMI (P = 0.003). Within study two, longissimus muscle objective color values were influenced by PAP where a* (redness; P < 0.001) and b* (yellowness; P < 0.04) values were negatively correlated with final PAP. These data begin to demonstrate the close relationship between live growth performance and pulmonary hypertension. More research is needed to better understand how cellular energy metabolism is potentially contributing to increased growth performance but negatively influencing muscle health in the form of oxygen binding capacity and inflammation. [ABSTRACT FROM AUTHOR]

To remain competitive in the industry, beef and dairy producers in the Midwest need to adapt to the use of alternative feeds and take advantage of the expected abundance and favorable pricing of biofuel coproducts. Integrating the coproducts as feed ingredients could make the livestock industry significantly more attractive and competitive in domestic and global markets. A survey instrument was created to inventory resources that currently limit (or enable) the use of biofuel coproducts by small and medium-sized beef and dairy producers in the state of Indiana. Seventy-eight of Indiana's 92 counties were represented in the survey results. [ABSTRACT FROM AUTHOR]