effect of supplementing saccharomyces cerevisiae to milk on the growth performance, white blood cell profile, skeletal indices, and rectal temperature in neonatal simmental calves

This study was conducted using 30 newborn calves with an average weight of 42.55 ± 0.98 kg in a completely randomized design comprising five treatments and six replicates over a 42-day period. saccharomyces cerevisiae (s. cerevisiae) yeast was mixed with the milk and administered to the calves in the morning. the experimental diets included: (1) a control diet without yeast, (2) 2.5 grams of live yeast, (3) 5 grams of live yeast, (4) 2.5 grams of inactive yeast, and (5) 5 grams of inactive yeast per calf per day. the calves were fed milk twice daily, in the morning and evening. body weight, skeletal indices, and rectal temperature (rt) were recorded every 21 days, while blood samples were collected at the end of the study. additionally, milk composition was analyzed. the results indicated that supplementation with 2.5 grams of inactive yeast resulted in the highest daily weight gain and the lowest feed conversion ratio (p < 0.05). except for eosinophil counts, other white blood cell components remained unaffected. yeast supplementation had no significant effect on rt or skeletal growth indices (p < 0.05). however, the addition of both live and inactive s. cerevisiae to the milk increased milk dry matter content, density, and conductivity. in conclusion, the supplementation of milk with live or inactive s. cerevisiae improved the growth performance of suckling calves.