Abstract:
The study was performed to examine the effect of fasting on quail chicks exposed to acute heat stress.
Fasting for 24 and 48 hours significantly reduced rectal temperature (Tr) (P < 0.05) compared with nonfasted group. The blood pH did not change by fasting but there was a significant fall in blood HC03- and pC02 levels in both the fasted groups for 24 and 48 hr relative to the other groups. In all groups, pH significantly increased (P <0.05) with the increase in Tr induced acute heat exposure but the rectal temperature in nonfasted group was significantly higher than in the fasted group (P<0.05). Although acute heat stress caused a sharp decline in blood pC02 (P<0.05) accompained by a fall in blood HC03 in all groups, the increase in pH and fall in pC02 and HC03 were more marked in nonfasted group. Heat induced haemodilution was more pronounced in fasted birds compared with those in non fasted groups. By resisting these results, fasting enhances the physiological adaptation of quails in response to acute heat stress, and the manipulations of diet might increase tolerance of quails to heat stress.