DAIRY-HERD INVESTIGATION - REDUCING HEAT-STRESS IN A NORTHEASTERN DAIRY

Because digestion generates heat in cattle, cows decrease their dry-ma tter intake in an attempt to reduce heat stress. As a result, heat str ess can cause production losses, in dairies. This column discusses the effectiveness and cost-effectiveness of modifications that were made to reduce heat stress in a dairy in Connecticut. The facilities of thi s dairy were typical of those found in Northeastern dairies (i.e., the y were not designed to prevent heat stress). Improvements in ventilati on and the installation of an evaporative cooling system (fans and spr inklers) and shade cloth caused dramatic improvements in ambient tempe rature for the cows. This led to significant improvements in productiv ity in comparison with the previous year. The results indicated that h eat and humidity were no longer causing a significant loss in milk yie ld. The dairy probably recovered the cost of the improvements made to the facility during the first summer of use.