Fetal Programming Influence on Microbiome Diversity and Ruminal and Cecal Epithelium in Beef Cattle.

We explored the influence of maternal nutritional strategies on the development of the rumen and cecum in offspring. Additionally, we investigated the potential repercussions of prenatal nutrition on the rumen and fecal microbiota composition, utilizing metagenomic 16S techniques, to understand the effects of fetal programming (FP) in Nellore cattle. A total of 63 bulls submitted to different prenatal nutrition strategies, namely, non-programming (NP), partial programming (PP), and complete programming (CP), were evaluated. The rumen epithelium was methodically evaluated based on the presence of rumenitis and structural irregularities. The assessment of cecum lesions was conducted post-evisceration, whereby all thoroughly cleaned ceca were methodically evaluated. Samples from 15 animals of rumen fluid at slaughter and feces during the finishing phase were collected, respectively. All DNA extraction were carried out using the Macherey Nagel NucleoSpin Tissue®, and 16S sequencing was conducted using the V4 primers on the MiSeq platform. Within the ruminal ecosystem, an estimated range of 90 to 130 distinct amplicon sequence variants was discerned, as distributed across 45,000 to 70,000 sequencing reads. Our metagenomic exploration unveils microbial communities that distinctly mirror gastrointestinal tract microenvironments and dietary influences. In sum, this comprehensive study advances our comprehension of FP, highlighting the interplay of maternal nutrition, gastrointestinal development, and microbial communities, contributing significantly to the fields of animal science.

Different prenatal supplementation strategies and its impacts on reproductive and nutrigenetics assessments of bulls in finishing phase.

This study investigated the effect of different prenatal nutrition approaches in 126 pregnant Nellore cows on reproductive and nutrigenetic traits of the male offspring during the finishing phase. For that purpose, three nutritional treatments were used in these cows during pregnancy: PP - protein-energy supplementation in the final third, FP - protein-energy supplementation during the entire pregnancy, and NP - (control) only mineral supplementation. The male progeny (63 bulls; 665 ± 28 days of age) were evaluated for scrotal circumference, seminal traits, number of Sertoli cells and testicular area. We performed a genomic association (700 K SNPs) for scrotal circumference at this age. In addition, a functional enrichment was performed in search of significant metabolic pathways (P < 0.05) with inclusion of genes that are expressed in these genomic windows by the MetaCore software. With the exception of major sperm defects (P < 0.1), the other phenotypes showed no difference between prenatal treatments. We found genes and metabolic pathways (P < 0.05) that are associated with genomic windows (genetic variance explained >1%) in different treatments. These molecular findings indicate that there is genotype-environment interaction among the different prenatal treatments and that the FP treatment showed greater major sperm defects compared to the NP treatment.

Effects of Different Prenatal Nutrition Strategies on the Liver Metabolome of Bulls and Its Correlation with Body and Liver Weight.

This study investigated the effect of prenatal nutrition on liver metabolome and on body (BW) and liver weight (LW) of Nellore bulls at slaughter. Three treatments were applied in 126 cows during pregnancy: NP­control (mineral supplementation); PP­protein-energy supplementation in the third trimester; and FP­protein-energy supplementation during the entire pregnancy. Offspring BW and LW were evaluated, and a targeted metabolomics analysis was performed on their livers (n = 18, 22.5 ± 1 months of age). Data were submitted to principal component analysis (PCA), analysis of variance (ANOVA), enrichment analysis, and Pearson's correlation analysis. The phenotypes did not show differences between treatments (p > 0.05). Metabolites PCA showed an overlap of treatment clusters in the analysis. We found significant metabolites in ANOVA (p ≤ 0.05; Glycine, Hydroxytetradecadienylcarnitine, Aminoadipic acid and Carnosine). Enrichment analysis revealed some biological processes (Histidine metabolism, beta-Alanine metabolism, and Lysine degradation). Pearson's correlation analysis showed 29 significant correlated metabolites with BW and 1 metabolite correlated with LW. In summary, prenatal nutrition did not show effects on the phenotypes evaluated, but affected some metabolites and biological pathways, mainly related to oxidative metabolism. In addition, BW seems to influence the hepatic metabolome more than LW, due to the amount and magnitude of correlations found.