Milk production efficiency in Gir crossbreds.

摘要

3235 lactation records of 1072 Gir crossbred cows maintained at the Cattle Project Rahuri between 1972 and 1992 were used to calculate milk production efficiency (MPEK, lactation milk yield/body weight at first calving). MPEK ranged from 6.14 in theinterse of Holstein X Gir crossbreds to 8.42 in Holstein X Gir and was generally the highest in 3-breed crosses, followed by 2 breed crosses and interse. The highest values for MPEKD (MPEK/first lactation length) were found for Holstein X (Jersey X Gir)(24.40 kg) and Holstein X Gir (24.00 kg) and the lowest values were for the interse of Swiss Brown X (Holstein X Gir) (18.20 kg) and Holstein X Gir (19.10 kg). Generally the highest MPEKD values were for 2-breed crosses, followed by 3-breed crosses andinterse.