growth performance, feeding behavior and physiological responses of young growing holstein male calves to dietary chromium-methionine (cr-met) supplementation related to body weight and age

This study was conducted to investigate the effect of dietary chromium-methionine (cr-met) supplementa-tion on growth performance, feeding behavior and physiological responses of holstein male calves during two different phases of body weight (bw). twenty six (153.5±9.83 kg of bw) male calves were divided in two groups (n=13) and randomly assigned to treatments: 1) control and 2) cr-met (1.1 mg cr/kg of diet on a dry matter (dm) basis). each phase consisted of 1 week pen acclimatization, 3 weeks diet adaptation and 1 week sample collection. after the first phase, all calves received the basal diet (without cr-met) for 6 weeks. after this period, the second phase started (240.1±12.15 kg bw). during the second phase treat-ments changed between 2 groups. calves fed with cr-met diet had lower dm intake and average daily gain (p<0.05) and rectal temperature (p<0.01) than the control group, whereas blood metabolites and feeding behaviors were similar between 2 groups during the first phase of experiment. during the second phase, calves fed with cr-met had greater dm intake, weight gain, average daily gain and standing time behavior (p<0.05) and lower blood glucose concentration, rectal temperature and resting time behavior (p<0.05) compared with calves fed with control diet. in conclusion, effect of feeding 1.1 mg cr/kg dm as cr-met supplement to holstein male calves on growth performance, blood glucose and resting and standing behavior might be related to body weight.