Spatial and temporal variations of temperature humidity index (THI) for laying hens in the Marmara region, Turkey

Abstract

Nowadays, global warming hence global climate change is one of the most important key issues for livestock production. Because of its negative effects on animal health and production costs, climate change induced heat stress in livestock has become more critical than ever. Laying hens are more sensitive to heat stress. Therefore adverse effect of heat stress on laying hens is more severe than other livestock. Out of several methods the temperature humidity index is the most commonly used tool to determine the effects of heat stress on livestock. In this paper temperature humidity index variations between 1974 and 2013 for laying hens throughout the Marmara in the western Turkey was examined. The temperature humidity index in collaboration with a Geographical Information System and indicator kriging were used to determine risky sites for laying hens production in the region. It is determined that increases in the calculated seasonal mean and mean maximum THI values are significant (P<0.001). Furthermore, mean and mean maximum THI values are generally tended to increase for investigated period. In terms of THI, Shore of Black Sea and southeastern Marmara were found to be more convenient locations for laying hens production in the study area. Based on the study findings, put into effect some mitigation strategies such as cooling, shading and feed arrangement is needed for successful laying hens production in the entire studied area except for shore of the Black Sea, and southeastern Marmara.