According to a 2×2 cross over design, 14 Holstein dairy cows were fed two isofibrous and isoenergetic TMR characterised by different crude protein: 14.5 % (LOW CP diet) or 16.5 % (HIGH CP diet). Milk yield and quality and metabolic profile were detected during the third week of each experimental period. Dietary treatment had no effect on DM intake (21.0 kg/d on average), milk yield (34.7 kg/d on average) and milk protein content (3.48 % on average). LOW CP fed cows showed a lower concentration of urea in milk (19.4 vs. 29.7 mg/dl; P<0.01), an increase of plasma albumin, glucose and creatinine and a reduction of plasma urea. In LOW CP treatment, the increase of creatinine was probably due to a higher catabolism of muscle protein. The efficiency of CP utilization was higher (0.39 vs. 0.34; P<0.05) on LOW CP treatment.
Changes in the metabolic profile and performance of dairy cows fed two dietary protein concentration
BERNARDINI, DANIELE;SEGATO, SEVERINO;MARCHESINI, GIORGIO;GERARDI, GABRIELE;ANDRIGHETTO, IGINO
2011
Abstract
According to a 2×2 cross over design, 14 Holstein dairy cows were fed two isofibrous and isoenergetic TMR characterised by different crude protein: 14.5 % (LOW CP diet) or 16.5 % (HIGH CP diet). Milk yield and quality and metabolic profile were detected during the third week of each experimental period. Dietary treatment had no effect on DM intake (21.0 kg/d on average), milk yield (34.7 kg/d on average) and milk protein content (3.48 % on average). LOW CP fed cows showed a lower concentration of urea in milk (19.4 vs. 29.7 mg/dl; P<0.01), an increase of plasma albumin, glucose and creatinine and a reduction of plasma urea. In LOW CP treatment, the increase of creatinine was probably due to a higher catabolism of muscle protein. The efficiency of CP utilization was higher (0.39 vs. 0.34; P<0.05) on LOW CP treatment.Pubblicazioni consigliate
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