Implementing fan cooling in barn to improve microclimate and milk yield of dairy cows

Abstract

The aim of this study was to evaluate the impact of fan cooling during hightemperature periods on barn microclimate, cow productivity, milk composition, and clinical indicators. The research was conducted at a commercial farm (Ukraine) where dairy cows were kept in two easy-to-assemble barns (with and without fans) during thermo-neutral (12 days) and hot (9 days) periods. The use of fans in the cowshed during the hot period helped to reduce the average daily temperature and relative humidity by 3.29 ºC and 1.88%, respectively. Indicators of rectal temperature and respiration rate of cows kept in a barn with fans were 0.35 ºC and 8.36 breaths/min lower as compared to cows in a barn without fans during the hot period. Similarly, milk yield in a barn with fans during the hot period decreased by 0.37 kg, and in a barn without fans by 2.64 kg. When keeping cows in a barn with fans during the hot period, the content of fat, protein and lactose in milk decreased by 0.03, 0.02 and 0.03%, while in a barn without fans were 0.11, 0.06 and 0.07%, respectively. Increasing of average daily air temperatures was a significant stressor for lactating cows housed in barns without fans. Implementing fans in barns during hot periods positively affected the microclimate, improving temperature, relative humidity, and climate indices.