Thirty two newborn Holstein calves were used in a completely randomized design trial from 1 to 10 weeks after birth to evaluate the effects of corn replacement with barley or triticale in calves starter on feed consumption, body weight gain, feed efficiency, weaning age, skeletal growth, rumen fluid pH, health status and blood metabolites. Grain portion of dietary treatments in starter diet were: 1- C with 100% corn, 2- B with 25% barley, 3- T25 with 25% triticale and 4- T50 with 50% triticale replacing corn. Starter Diets were formulated to be similar in protein (19%) and energy. All calves received 4kg/d whole milk from day 4 to the weaning time. Starter diet and water wer e offered ad libitum from day 4 to 70. In each treatment, 4 calves were randomly selected in order to take feces, rumen fluid and blood samples. Collected data were analyzed for three periods of 0-42, 43-70 and 0-70 days. In first period, feed intake, body weight gain and feed efficiency of calves in control treatment were lower, although these differences were not significant. The same effect on performance was also observed in second period. In overall period, feed intake and body weight gain were similar in all groups but feed efficiency tended to be lower in T50. Weaning age was not significantly lower in B25 and T50 compared with C or T25. At day 70, Rumen fluid pH was significantly lower (P= 0.05) in B or T50 compared with 25T or control diets. Comparing blood glucose and BHBA showed that no differences were observed between treatments but BUN was higher in T25 (P=0.0004) in second period compared with B25 or C. Dietary treatment had no effect on apparent nutrient digestibility in first period but corn replacement with barley or triticale significantly improved dry matter (P=0.03), organic matter (P=0/02) and NDF (P=0/07) digestibility in the later one. Partial replacement of corn with barley or triticale caused increase in whither height (P=0.004) at pre-weaning but did not influence other skeletal traits in pre or post-weaning time. The results of present study indicate that barley or triticale may be substituted for corn in calf starter without any adverse effects on performance of calves. Key words: Calves, starter, triticale, barley.
