chicken gut metagenome Raw sequence reads. chicken gut metagenome

Avi-Lution® is a defined, patented, synbiotic formula containing Saccharomyces cervisiae, Enterococcus faecium, and Bacillus spp. Broiler chickens (n = 1,250) were experimentally treated as unchallenged controls (uCon), infected controls (iCon) with Clostridium perfringens, or infected and treated with bacitracin methylene disalicylate (BMD) at 55 mg/kg or Avi-Lution® at 1.0 (AvL1) or 2.0 (AvL2) g/kg in feed for 42 d. Each treatment was applied to 10 replicate pens of 25 straight-run, newly hatched chicks. Pens treated with AvL1, AvL2, and BMD showed improved growth, feed efficiency, or mortality compared with iCon pens. Despite improved performance, AvL1 pens documented the greatest severity of infection-associated intestinal lesions. Concentrations of acetic acid and total volatile fatty acids (VFA) were lower in AvL1 jejunal contents, anterior to ecological changes in the cecum. Cecal propionic and valeric acids were significantly correlated (R2 > 0.57) for all treatment groups except AvL1 (R2 = 0.13), and AvL1-treated birds presented with decreased concentrations of cecal isobutyric, butyric, and valeric acids despite no difference in total VFA. The BMD and AvL2 treatments significantly affected infection-associated bacterial operational taxonomic units (OTU), as defined by 16S gene sequencing, but AvL1 treatment affected a distinct group of infection-associated OTU that were also associated with molar proportion of cecal butyric acid. Cecal propionic acid and propionate-associated OTU also were lower in iCon and infected-treated broilers, but dietary treatments altered the propionate-associated ecological relationships in the cecum. Avi-Lution® was thus found to exert dose-dependent, digestive ecological changes that coincided with improved broiler performance during challenge conditions.