Large datasets allow estimation of feed required for individual milk components or body maintenance. Phenotypic regressions are useful for nutrition management, but genetic regressions are more useful in breeding programs. Dry matter intake records from 8,513 lactations of 6,621 Holstein cows were predicted from phenotypes or genomic evaluations for milk components and body size traits.
View Article and Find Full Text PDFMineral metabolism, in particular Ca, and to a lesser extent phosphorus (P) and magnesium (Mg), is altered with the onset of lactation because of extensive irreversible loss to synthesize colostrum and milk. The transient reduction in the concentration of Ca in blood, particularly when it lasts days, increases the risk of mineral-related disorders such as hypocalcemia and, to a lesser extent, hypophosphatemia. Although the incidence of clinical hypocalcemia can be reduced by prepartum dietary interventions, subclinical hypocalcemia remains prevalent, affecting up to 60% of the dairy cows in the first 3 d postpartum.
View Article and Find Full Text PDFGenetic selection has remarkably helped U.S. dairy farms to decrease their carbon footprint by more than doubling milk production per cow over time.
View Article and Find Full Text PDFThe Resilient Dairy Genome Project (RDGP) is an international large-scale applied research project that aims to generate genomic tools to breed more resilient dairy cows. In this context, improving feed efficiency and reducing greenhouse gases from dairy is a high priority. The inclusion of traits related to feed efficiency (e.
View Article and Find Full Text PDFThe impact of genomic epistasis effects on the accuracy of predicting the phenotypic values of residual feed intake (RFI) in U.S. Holstein cows was evaluated using 6215 Holstein cows and 78,964 SNPs.
View Article and Find Full Text PDFOne objective was to evaluate the association of dry matter intake as a percentage of body weight (DMI%BW) and energy balance (EB) prepartum and postpartum, and energy-corrected milk (ECM) postpatum with digestive disorders postpartum. For this, ANOVA was used, and DMI%BW, EB, and ECM were the outcome variables, and left displaced abomasum (LDA), indigestion, and other digestive disorders (ODDZ) were the explanatory variables. The main objective was to evaluate prepartum DMI%BW and EB as predictors of digestive disorders.
View Article and Find Full Text PDFThe objectives were the determine the effects of presynchronization with PGF 2 days before the 5-d timed artificial insemination (AI) protocol on ovarian responses and pregnancy per AI (P/AI) in dairy heifers. The hypothesis was that PGF would induce responsive heifers to be in proestrus at the initiation of the timed AI protocol, which was expected to improve ovulatory responses and P/AI. Weekly cohorts of Holstein heifers were blocked by age and, within block, randomly assigned to remain as control (CON; n = 255) or receive PGF on experiment Day -10 (PG; n = 255).
View Article and Find Full Text PDFBroad-spectrum antibiotics such as ceftiofur and ampicillin are recommended for the treatment of metritis in dairy cows. Nonetheless, little is known about the impacts of antibiotics on the uterine microbiota. Here, we evaluated the shift in uterine microbiota after treating metritic cows with ceftiofur or ampicillin, and also gained insight into the uterine microbiota associated with cure of metritis.
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