Effect of Shed Designing on Physiological Responses and Semen Quality of Crossbred Bulls during Various Seasons

The study aimed to evaluate the effect of shed designing on microclimatic variables, physiological responses and semen quality parameters of breeding bulls during different seasons. Thirty-one adult Frieswal (Holstein Friesian and Sahiwal cross) breeding bulls were distributed into four groups i.e. in traditional sheds (TG) having open area in north (TGN-8 bulls) and south directions (TGS-8 bulls) and in modified sheds (MG) having open area in east (MGE-8 bulls) and west directions (MGW-7 bulls). The sides of bull pens in traditional (east-west oriented) and modified sheds (north-south oriented) were covered and open, respectively. Biweekly semen ejaculates were evaluated for volume, sperm concentration and initial sperm motility. Significantly (P<0.05) lower THI (temperature humidity index) value in the afternoon period was observed in MG than in TG during hot and humid season. The bulls of TG had significantly higher (P<0.05) rectal temperature than those kept in MG during hot and humid season. Heart rate did not show any pattern in bulls during different seasons. Respiration rate (RR) in the bulls of all sheds were higher (P<0.05) during hot-dry and hot-humid seasons than in the other seasons, however, shed design had no effect on RR of bulls during different seasons. Significantly (P<0.05) higher initial motility was observed in bulls of MG than in the TG except during comfortable season. In conclusion, the modified sheds were comparatively better than traditional sheds as far as THI, physiological responses and initial progressive motility in breeding bulls are concerned.