Dietary BCT-7112 Supplementation Influences Performance, Egg Quality, Ammonia Emission, and Cecal Microbiome in Laying Ducks.

This study evaluated the effects of BCT-7112 on laying duck performance, egg quality, ammonia emission, and cecal microbiota. Two hundred twenty 32-week-old Khaki Campbell ducks were assigned to four dietary treatments (0, 200, 500, or 1000 ppm Toyocerin 10 premixture, containing 1 × 10⁹ BCT-7112 CFU/g) with five replicate pens of eleven birds each. Data on productivity, egg quality, and ammonia emissions were collected weekly, and cecal microbiota were analyzed at 44 weeks of age. Supplementation with 1000 ppm BCT-7112 significantly increased average egg weight ( < 0.001) and eggshell thickness ( = 0.007). Egg mass also improved at higher supplementation levels ( < 0.05), though feed intake, feed conversion, daily egg production, and most egg quality parameters were unaffected ( > 0.05). Ammonia emissions in litter decreased significantly ( < 0.05) with probiotic inclusion. Cecal microbiota analysis revealed higher diversity in ducks fed 1000 ppm, with a notable shift in predominant phyla from Bacteroidetes (35.12%) and Firmicutes (34.93%) in the controls to Bacteroidetes (40.52%), Firmicutes (34.08%), and Deferribacteres (9.54%) in the treated ducks. The findings suggest that 1000 ppm BCT-7112 enhances egg production, eggshell quality, and microbial diversity while reducing ammonia emissions in laying duck systems.