E. Pakar, M.H. Fathi Nasri, A. Riasi and M.A. Naseri

 (Journal of Animal Science Researches . 22(1): 37-51)

Abstract (The full text in Persian language)

Thirty Holstein calves (15 males and 15 females) were used to evaluate the effects of feeding steam-rolled barley grain on feed intake, weight gain, feed efficiency, rumen metabolites and weaning age. Average birth weight of calves was 40.1_+ 0.8 kg. The experimental diets were as: 1- starter containing ground barley, 2- starter containing dry rolled barley and 3- starter containing steam-rolled barley. All experimental diets were formulated to be iso energetic and iso nitrogenous, and offered from the first day of experiment (3 days age). During the experiment, calves were fed raw milk based on 10% of their birth body weight and they were taken out two weeks after weaning. Experimental data were analyzed based upon a completely randomized design in which there were 3 treatments and 10 replicates per each treatment. The results of this study showed that there was not statistically significant differences among experimental diets regarding average daily feed intake, average daily gain, and average feed efficiency in pre and post weaning period. Calves fed diet 3 at wk 6, two wk after weaning and in whole period of experiment had significantly (P<0.05) greater rumen propionate concentrations than those fed diets 1 and 2. Calves fed diets 1 and 2 at two wk after weaning and whole period of experiment had significantly (P<0.05) greater rumen butyrate concentrations than those fed diet 3. The results of this study showed feeding steam-rolled barley grain to calves from the first week after birth although affect some VFAs concentration, but did not affect performance and weaning age of Holstein calves.

Keywords: Calf, Weaning age, Steam-rolled barley, Rumen metabolites