January 15, 2026

Interpretive Summary: Effects of feeding a Bacillus-based probiotic on nutrient utilization and microbiota profile in the rumen and reproductive tract of beef heifers receiving a forage-based diet

Interpretive Summary: Effects of feeding a Bacillus-based probiotic on nutrient utilization and microbiota profile in the rumen and reproductive tract of beef heifers receiving a forage-based diet

By: Izadora S De Souza, Reinaldo F Cooke, Shea J Mackey, Thainá Minela, Zachary K Seekford, Giuseppe Copani, Raphaele Gresse, Kelsey M Harvey, Ky G Pohler, João M B Vendramini, Bruno I Cappellozza

To meet the growing demand for beef driven by a rising population, cattle operations must improve efficiency of nutrient utilization by the rumen and the entire digestive tract. This can be achieved by enhancing forage quality or implementing nutritional strategies that optimize forage and overall nutrient digestibility, such as supplementing cattle with Bacillus-based probiotics. Reproductive efficiency is a critical determinant of cattle availability for beef production, and probiotics may enhance fertility by modulating the microbial communities in the female reproductive tract. Therefore, this experiment evaluated the effects of a Bacillus-based probiotic on nutrient utilization, physiological responses, and reproductive tract microbiota of beef heifers fed a forage-based diet. Results showed improved ruminal and overall nutrient utilization with probiotic supplementation. Changes in the reproductive bacterial communities were limited to vagina, but suggested a healthier vaginal environment. Collectively, this experiment provides novel insights on how supplementing a Bacillus-based probiotic can enhance the utilization of forage nutrients by growing beef cattle, with benefits to vaginal microbiota that may result in improved fertility.

Read the full article in the Journal of Animal Science.