Bioclimatic zoning for dairy cows in Brazil by statistical modeling

BACKGROUND Climate conditions affect animal welfare directly, influencing milk production. The Midwest region is the largest cattle‐producing region in Brazil. The objective of this study was to elaborate on bioclimatic zoning for dairy cattle in the Midwest region of Brazil. Air temperature (Ta, °C) and relative humidity (%, RH) data from a 30‐year historical series (1989–2019) collected by the National Aeronautics and Space Administration/Prediction of Worldwide Energy Resources (NASA/POWER) platform were used. The Temperature and Humidity Index (THI) was determined for the hottest and coldest months. Milk production losses due to climate factors in the Midwest of Brazil for two daily production levels, 10 kg Milk (PL10) and 25 kg Milk (PL25), were estimated. RESULTS The Midwest presented three THI classifications throughout the year: ‘normal’, ‘alert’, and ‘critical alert’. The entire Midwest region was classified as ‘normal’ (THI