Effect of environmental factors on lactation milk yield and lactation length of murrah buffaloes

摘要

The study was undertaken to evaluate the effect of different macro climatic variables on lactation milk yield and lactation length of Murrah buffaloes. Milk data of 187 Murrah buffaloes with 1195 lactation records and the meteorological data over a period of 25 years (1985-2009) were obtained from Department of Animal Husbandry and Dairy Science, Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani and University Meteorological Observatory, respectively. The influence of environmental factors on lactation milk yield and lactation length was significant (P< 0.01). It was observed that lactation milk yield was highest (1257.12 + 29.50 lit) among the Murrah buffaloes calved during winter season as compared to rainy (1088.0 + 18.41) and summer season (982.42 + 15.56). All the climatic variables considered in the study accounted for 54.90 %, 29.70 % and 45.10 % direct variation on lactation milk yield in rainy, winter and summer season, respectively, as verified by the value of coefficient of determination (R2). This research indicates that Murrah buffaloes were sensitive to seasonal changes on their lactation length and lactation milk yield.. The meteorological observation during the period of study confirmed that there was high value of THI in sevenmonths (March- September) in a year, which suggests that most buffaloes are exposed to negative effects of heat stress in this region and demanding additional productive strategies like improving environment, management and comfort level of cows for maintaining their lactation performance