Abstract
Organic acids are readily absorbed in the upper gastrointestinal tract, which hinders their optimal delivery to segments where gut health issues mostly occur. Glycerol esters of butyric and valeric acid (BVg) are known for their capacity to release acids within the small intestine. This study evaluated the impact of BVg on the performance and gut health of broilers under a sub-clinical necrotic enteritis (NE) challenge. A total of 1200 Cobb 500 chicks were assigned to four treatments: 1) UC- unchallenged control, 2) CC- NE challenged control, 3) BVg- CC plus BVg (1000, 500, 250 g/ton in starter, grower, and finisher phases), and 4) ANT- CC plus zinc bacitracin and salinomycin. NE challenge was induced via oral gavaging of Eimeria spp. vaccine (d9) and Clostridium perfringens (d14 and d15). Data was analyzed using JMP 16.0 employing one-way and two-way ANOVA with Tukey's test to separate means, and Kruskal-Wallis test was used for non-normally-distributed data. During challenge period (d8-19), BVg-fed birds showed an improvement in AWG and FCR, shifting performance from CC towards UC (P > 0.05). Over d0-35, BVg group had similar performance with CC, however there was no significant difference observed among the BVg, ANT, and UC groups (P > 0.05). Male birds supplemented with BVg had a Bifidobacterium population nearly equivalent to those in the UC and ANT groups. The BVg supplementation showed a similar expression of IL6 and occludin with UC and ANT groups and had a shift of expression of IL6 from CC towards ANT group, and MUC2 and B(o)AT from CC towards the UC group. Furthermore, additive supplementation shifted the oocyst counts from CC group towards the UC and ANT groups (P > 0.05). In conclusion, BVg has the potential to alleviate the NE-induced performance loss and gut health deterioration by modulating gut-centric gene expressions and microenvironment. Further research is warranted to explore its efficacy with varying combinations of other additives under different challenge models.