An evaluation of risky sites for cattle production in northern Turkey based on temperature/humidity index calculated using GIS and indicator kriging

Abstract

High temperatures and relative humidity can induce livestock stress and a subsequent decrease in productivity, making location and time period important elements to consider when planning cattle and dairy farming investments. Turkey has a diversity of geographical features that offer the potential for breeding of all types of animals. This study used the temperature/humidity index (THI) in conjunction with a Geographical Information System (GIS) and indicator kriging to identify risky sites for cattle production in 4 provinces in northern Turkey. Findings indicated that THI values at 0700 and 2100 local time (LST; UTC + 2 h) fell within the normal range for all months. However, daily maximum THI values were found to vary significantly by month, exceeding the alert threshold THI value = 75 at certain sites in June, July, August and September and the danger threshold THI value = 79 at certain sites in July and August. THI values at 1400 LST in July and August also exceeded the alert threshold at certain sites and the danger threshold at others. Once THI values were calculated, regression analysis was performed using THI values and selected topographical features. A significant correlation (at 1%) was found between THI values and elevation for all months except April and May. The study findings suggest that cattle producers should invest in physical improvements such as shade provision and cooling fans and shift feeding times to cooler hours of the day in June, July, August and September in order to mitigate the negative effects of high temperatures and relative humidity.