Influence of Rumen Protected Methionine and Lysine Supplementation on Milk Production, Composition and Nutrient Utilization in PeriparturientDairy Cows

摘要

A study was conducted to investigate the effect of supplementing rumen protected methionine (RPL) and lysine (RPL) on milk production, composition and nutrient utilization in periparturient crossbred cows (Bos taunts x Bos indicus). Eighteen crossbredcows were divided into two groups (9 each) on the basis of most probable production ability (MPPA) and lactation number. Animals in control group (C group; MPPA = 4119 kg), were fed chopped wheat straw, chaffed green maize fodder and concentrate mixtureas per requirements (NRC, 2001). However, animals in supplemented group (S group; MPPA = 4120 kg), were fed same ration as fed to control group plus 5 g RPM and 20 g RPL, prepartum and 7 g RPM and 60 g RPL, postpartum. The experimental period started from 30 days before expected date of parturition to 90 days post parturition. Milk yield during supplementation period in group S was 17.36 kg/d, which was 14.21% higher (P<0.05) in group S than that of group C (15.20 kg/d). Milk fat, protein and lactose yield per day was higher (P<0.05) by 17.39, 14.86 and 13.91% in group S than that of group C, respectively. The efficiency of utilizing DMI (kg) per kg milk production was 0.79 and 0.69 for group C and S, respectively. The CP, MP, TDN, ME and NEL intake (kg) per g milk production was also better in group S than that of group C. Therefore, supplementation of rumen protected methionine and lysine increased milk production and milk fat, protein and lactose yield in periparturient dairy cows.