Effect of climatic variables on average daily milk production in crossbred cattle

Abstract

The effect of climate variables on average daily milk production (milk yield/cow/day) was examined in crossbreds of Hariana with Holstein-Friesian, Brown Swiss and Jersey. The correlations of average daily milk yield with wet bulb temperature and relative humidity were negative and significant whereas with temperature, the correlation though negative was nonsignificant. The correlations of meteorological indices with average daily milk yield were in general negative and nonsignificant. The regression coefficients of average daily milk yield on temperature lind all the indices were negative and nonsignificant while thilt on relative humidity was negative and significant. The regression of average daily milk yield on temperature and humidity taken together was, however, negative and significant (-3.397±0.887). Temperature and humidity together explained 62.15% of variation in milk yield/cow/day which was higher than that explained either by temperature or humidity alone and the indices indicating that temperature and humidity combination in absolute values should be taken instead of constructing meteorological indices for explaining variation in milk yield/cow/day.