Effect of feeding yeast culture on ruminal fermentation and blood indicators of Holstein dairy cows

Abstract

The experiment was conducted to evaluate the effect of yeast culture ( Saccharomyces cerevisiae ) supplementation on ruminal fermentation in 20 Holstein dairy cows divided into control and experimental groups, each group of 10 cows. The animals received a diet based on maize silage (19 kg), alfalfa silage (15 kg), meadow hay (1.5 kg), extracted rapeseed meal (1 kg) and concentrate mixture (9.5 kg). The diets were fed as a total mixed ration. The supplement of yeast culture Levucell ® SC 20 ( Saccharomyces cerevisiae – CNCM I-1077; min. content 2 × 10 10 CFU·g -1 ) was added to the concentrate mixture in the ration fed to the experimental group of animals. The addition of yeast culture significantly ( P < 0.01) increased ruminal pH but had no positive effects on the increased production of volatile fatty acids. The supplementation of yeast culture significantly ( P < 0.01) increased numbers of protozoa in the rumen of dairy cows of the experimental group (361.3 ± 18.315) compared to the control group (308.3 ± 37.505). The addition of yeast culture significantly ( P < 0.01) increased concentration of serum glucose, calcium, phosphorus, copper, zinc, magnesium and AST ( P < 0.05). As compared to the control group (4.948 ± 0.0384 mmol·l -1 ), the level of urea in the blood serum was significantly decreased ( P < 0.01) in the experimental group of cows. Our results show that the supplementation of Saccharomyces cerevisiae culture at recommended doses enhances ruminal fermentation which may have a positive effect on milk production and health status of Holstein dairy cows.