Association of ionophores, yeast, and bacterial probiotics alters the abundance of ruminal microbial species of pasture intensively finished beef cattle

AbstractThe effect of the association of non-protein nitrogen, yeast, and bacterial probiotics on the ruminal microbiome of beef cattle intensively finished on pasture was evaluated. The experiment was carried out in a completely randomized design with five treatments and four replications. The treatments consisted of a group of animals kept on pasture that received low consumption supplementation (LS) and four groups that received for 98 days, 17.5 g concentrate kg−1 body weight. The supplements were composed of the association of additives: urea (U), slow-release non-protein nitrogen (U+SRN), yeast (Saccharomyces cerevisiae; U+SRN+Y), and bacterial probiotics (live strains of bacteria; U+SRN+Y+BP). All supplements also contained salinomycin and virginiamycin. After slaughtering the animals, samples of ruminal content were collected to quantify groups of fibrolytic bacteria (Ruminococcus albus andFibrobacter succinogenes), non-fibrolytic (Prevotella ruminicola, Selenomonas ruminantium, andStreptococcus bovis), Archaea, and ciliate protozoa, using the qPCR technique. The abundance ofF. succinogenes was the same for the LS animals and those that received the supplement U+SRN+Y (1.42 ×108 copies mL−1) but higher than the other treatments. Supplementation reduced by 90% the abundance ofS. bovis compared to the LS. The inclusion of yeast increased the abundance of fibrolytic bacteria by 2.2-fold. For animals that received the supplement U+SRN+Y+BP and the LS, there was no di...
Source: Tropical Animal Health and Production - Category: Veterinary Research Source Type: research