Milk Production of Buffaloes and Causes of Calf Mortality under a Semi-Intensive Production System in Egypt

Abstract

Records of 71 buffaloes, raised under a semi-intensive production system in a university herd, collected from 1993 to 1999, were used to study the effect of some nongenetic factors on milk performance and causes of calf mortality. The averages of the milk yield, lactation length, calving interval, daily milk yield and proportion of lactation length on the calving interval were 1626 kg, 305 days, 431 days, 7.4 kg and 0.714, respectively. The calving season (P < 0.05) and parity significantly (P < 0.001) affected the milk yield. The calving interval as the only reproductive trait was significantly (P < 0.001) affected by the calving season. The year of calving had no significant (P > 0.05) effect on the traits studied. The daily milk yield and proportion of lactation length in the calving interval were not significantly (P > 0.05) affected by the calving year, calving season and parity. The average persistency of the milk yield was 73%. Yearly calf mortality rates were 19, 33, 25.5, 25 and 12%, whereas those of buffaloes were 2.3, 2.3, 2.2, 6.6 and 2.1% during the five years of the veterinary study. Seasonal raw mortality rates of calves were high during the winter (53.6%), followed by spring and summer (17.3 and 12%). The complex “light body weight at birth-pneumonia-bad management” caused 71.4% of total calf mortality during the period of the study. The year of calving had a significant (P < 0.01) effect on the number of calves that died and that died by particular from pneumonia, and a highly significant (P < 0.001) effect on the light body weight at birth.