Effect of Saccharomyces cerevisiae on growth performance, nutrient digestibility, serum metabolites and feeding behavior of Simmental dairy calves

Effect of Saccharomyces cerevisiae on growth performance, health index, nutrient digestibility, serum metabolites and feed intake behavior of dairy calves using 18 Simmental dairy male calves aged about 20 days and initial body weight 47±2.4 kg was studied in a completely randomized design with 3 treatments and 6 replications. Treatments included: 1- control group (without yeast), 2- treatment containing 2.5 grams of Saccharomyces cerevisiae yeast per day and 3- treatment containing 5 grams of Saccharomyces cerevisiae yeast per day. The experimental period lasted 60 days, which the first 7 days were considered as adaptation period. Dry matter intake and daily weight gain were measured, and feed conversion ratio was calculated. Digestibility of nutrients and blood metabolites were also determined. The calves received 5 grams of yeast had higher weight gain and better feed conversion ratio (P<0.05). Blood glucose, cholesterol, triglyceride, and nitrogen urea concentrations were not affected by experimental treatments. The digestibility of dry matter was higher in dairy calves consuming 5 grams of yeast than the control group (P< 0.05). According to the results of the present study, the use of yeast increased daily weight gain and dry matter digestibility and improved feed conversion ratio. Therefore, Saccharomyces cerevisiae yeast can be used in dairy calf diets at a level of 5 grams per day.