Effect of Climatic Variability on the Reproduction Performances of Murrah Buffalo

Abstract

The impact of climatic change on the reproductive capabilities of Murrah buffaloes at Hisar (LUVAS) was assessed in this study. A dataset of 2351 inseminations (2009-2017) was scrutinized for conception rates, alongside 439 calvings (2001-2016) which were evaluated for service period and calving interval. Daily maximum and minimum temperatures as well as relative humidity were acquired from the Agriculture Meteorology Department of CCSHAU, Hisar. Results indicated that the chances of achieving pregnancy were significantly higher (p < 0.01) at an Index of Temperature and Humidity (THI) ≤ 70, being 1.35 times higher than at THI-4. Pregnancy ratios at higher THI categories (THI-2, 3, and 4) were more or less the same with THI-2 (70-75) having a 1.23 times greater probability of conception in comparison to THI-4. Conception rates were seasonally consistently statistically significantly influenced (χ2=12.79; p<0.01), showing 0.69 times lower probability than pregnant women in Season-1 (Mar-Apr-May) vs in Season-4 (Dec-Jan-Feb). A trend was noted for Season-2 (Jun-Sep) where a significantly lower probability (p < 0.05) of pregnancy was observed in comparison to Season-4. The study concluded that calving in Oct-Nov and THI of below 80 is preferred as it minimizes service periods and calving intervals. The impact of these factors on postpartum reproductive physiology, specifically on ovarian activity, metabolic and hormonal environments, and oestrus expression in the early postpartum phase, requires more investigation.