author(s)
CP Ghosh, S Datta, NK Tudu and SS Kesh

abstract
24 Karan Fries cows in early lactation with good body condition (>3 at 6 point scale) were randomly allotted to four treatments to study the impact of modified microclimate on production performances. Treatments were; Shed (T1), Shed with fan (T2), Shed with fan and water bath (T3) and Shed with fan and sprinklers (T4). The T4 group had lower maximum, minimum, dry bulb as well as wet bulb temperatures and Thermal Humidity Index than other treatment groups. The rectal and skin temperatures, respiration and heart rates of animals were lower in T4 group. Composition of various milk constituents didn’t differ significantly (P>0.05) by various cooling strategies. Higher milk yield was recorded for the animals which were provided evaporative cooling system. Highest overall milk yield was recorded in the animals of T4 group followed by T3, T2 and T1 groups. Thus, evaporative cooling system (T4) was proved to be the best strategy to maximize production in the summer season.