Describing the cecal microbiota development in broilers when fed varying levels of a yeast culture product

The objective was to evaluate a yeast culture product, ProBiotein® (PB), on the cecal microbiome development of Ross 308 males fed PB supplemented diets for 42 d. Diets were offered ad libitum and consisted of an industry-standard basal diet (CON), basal + 0.0% PB (0.0PB)., basal + 0.5% PB (0.5PB), or basal + 0.75% PB (0.75PB). Chicks were randomly assigned to batteries using an RCBD on d 0 (n = 400, n = 10, k = 4, r = 2) and moved to floor pens on d 14 following the same blocking patterns. Starter, grower, and finisher phases were fed in 14-d intervals. On d 14, 28, and 42, 10 birds per treatment were euthanized, and cecal digesta was collected. Genomic DNA were extracted, and the V4 region of the 16S rRNA gene was sequenced on an Illumina MiSeq. Sequencing data were analyzed in QIIME2–2022.2. Treatment, block, day effects, and the interactions between were analyzed on α and β diversity using ANOVA and ADONIS with significance determined at P < 0.05. Pairwise differences were determined using Kruskal-Wallis (α) or ANOSIM (β) (P < 0.05, Q <0.05). Microbiome maturity was evaluated per treatment using MAZ scores (P < 0.05). Significantly different taxonomical relative abundances were determined using ANCOM. Significant interactions across α and β diversity revealed shifts in cecal microbiota due to both treatment and day (P< 0.05, Q <0.05). The treatment × day ANCOM revealed 51 significantly different relatively abundant taxa at the genus level (120 < W <160, P < 0.05). The MAZ scores showed a steady microbial maturity from d 14 to 42 for birds fed CON. Maturity for those fed 0.2PB and 0.5PB decreased sharply at d 28 but increased sharply toward similar scores as those fed CON. The MAZ scores for those fed 0.75PB decreased steadily from d 14 through d 42. Results show that microbiota development over time can be modulated by dietary treatments and should be accounted for when evaluating feed amendments. In conclusion, PB was shown to influence microbiota development and may be a useful feed additive in promoting microbial diversity in the ceca.

Key Words: microbiome, microbiota, yeast fermentate, broilers.

Presented at the 10th Symposium on Gut Health in Production of Food Animals 2022, St. Louis, USA.