Effect of naked neck gene on body temperature of broilers in two extreme seasons
ATAL BAHADUR, I.S. BAJWA AND BHUPINDER SINGH
Deptt. of Animal Breeding and Genetics
PAU, Ludhiana - 141 004
A total of 476 naked neck chicks (both NaNa and Nana) and their normal sibs from 20 sires in summer, and 340 chicks from 12 sires in winter season were raised to six weeks of age on deep litter. Rectal temperature as a measure of body temperature (BT) was observed twice for each bird, first on the afternoon of 42 nd day (BT1) and then on the morning of 43 rd day (BT2) before recording the body weights. The clinical thermometer was inserted about 3 cm deep into cloaca and held for 60 seconds. The trial was carried out both in summer and winter seasons. There was either no difference in BT between naked neck and normal birds or a slightly lower BT (0.1° to 0.2°F) for naked neck birds in the evening during summer season. In winters, the naked neck males showed a lowering of BT by 0.4°F than the normal ones, a value much different than the corresponding value in females (0.1°F). There was no difference in the BT2 of the two phenotypes in the mornings in both the seasons. Slightly lower BT in the afternoons even in summer season i.e., at the end of relatively warmer period indicated the possibility of naked neck birds having a different BT response than normally feathered birds.