Skip to main content

Effect of active dry yeast on lactation performance, methane production, and ruminal fermentation patterns in early-lactating Holstein cows.

  • 2021-01
  • Journal of Dairy Science 104(1)
    • Yan Li
    • Yizhao Shen
    • J. Niu
    • Yanfei Guo
    • Mirielle L Pauline
    • Xiaojing Zhao
    • Qiufeng Li
    • Yufeng Cao
    • Chongliang Bi
    • Xiujiang Zhang
    • Zhonghua Wang
    • Yanxia Gao
    • Jianguo Li


This study was conducted to examine the effect of active dry yeast (ADY) supplementation on lactation performance, ruminal fermentation patterns, and CH4 emissions and to determine an optimal ADY dose. Sixty Holstein dairy cows in early lactation (52 ± 1.2 DIM) were used in a randomized complete design. Cows were blocked by parity (2.1 ± 0.2), milk production (35 ± 4.6 kg/d), and body weight (642 ± 53 kg) and assigned to 1 of 4 treatments. Cows were fed ADY at doses of 0, 10, 20, or 30 g/d per head for 91 d, with 84 d for adaptation and 7 d for sampling. Although dry matter intake was not affected by ADY supplementation, the yield of actual milk, 4% fat-corrected milk, milk fat yield, and feed efficiency increased quadratically with increasing ADY supplementation. Yields of milk protein and lactose increased linearly with increasing ADY doses, whereas milk urea nitrogen concentration and somatic cell count decreased quadratically. Ruminal pH and ammonia concentration were not affected by ADY supplementation, whereas ruminal concentration of total volatile fatty acid increased quadratically. Digestibility of dry matter, organic matter, neutral detergent fiber, acid detergent fiber, nonfiber carbohydrate, and crude protein increased quadratically with increasing ADY supplementation. Supplementation of ADY did not affect blood concentration of total protein, triglyceride, aspartate aminotransferase, and alanine aminotransferase, whereas blood urea nitrogen, cholesterol, and nonesterified fatty acid concentrations decreased quadratically with increasing ADY supplementation. Methane production was not affected by ADY supplementation when expressed as grams per day or per kilogram of actual milk yield, dry matter intake, digested organic matter, and digested nonfiber carbohydrate, whereas a trend of linear and quadratic decrease of CH4 production was observed when expressed as grams per kilogram of fat-corrected milk and digested neutral detergent fiber. In conclusion, feeding ADY to early-lactating cows improved lactation performance by increasing nutrient digestibility. The optimal ADY dose should be 20 g/d per head.

Keywords: methane emission; milk production; nutrient digestibility; yeast product.

Research Insights

SupplementHealth OutcomeEffect TypeEffect Size
Active YeastImproved DigestibilityBeneficial
Active YeastImproved Lactation PerformanceBeneficial
Active YeastReduced Methane ProductionBeneficial
Active YeastReduced Somatic Cell CountBeneficial

Pillser helps you make informed health decisions by providing comprehensive, unbiased information about supplements. This includes detailed research on supplement ingredients, their benefits, potential risks, and their overall efficacy. You can contribute by sharing your feedback and suggestions.

Send us an email at