Comparison the effects of feeding yeast probiotic in milk or starter on growth performance, health, blood and rumen parameters of Holstein calves

To evaluate the effect of feeding yeast probiotic in milk or starter on growth, fecal score, health, blood and rumen parameters, 30 female Holstein calves with average 40.4±1.8 kg birth weight in Taliseh Nemouneh dairy farm used from 14 until 65 days old. Calves randomly divided to 3 treatments including: 1) control (without probiotic) 2) yeast probiotic in starter 3) yeast probiotic in milk. Average daily gain, body weight and feed efficiency were not significantly different between treatments. Dry matter intake was significantly lower in treatment 2 than control (P<0.01). Digestibility of feed nutrients, ammonia nitrogen concentration, rumen fluid pH and blood parameters did not affected by treatments. Fecal score and health in treatment 2 and 3 were better than control. Generally, calves were fed with yeast probiotic in milk had the best fecal score and health