The effect of ambient temperature and energy level on reproduction in Red-Legged partridges

The effects of temperature and dietary energy on various reproductive parameters were studied in Red-Legged partridges (Alectoris graeca) reared in three environmental chambers at either 18.3, 23.9, or 29.5 C. These birds were then cycled through two consecutive production periods. In Period 1, at 38 weeks of age, the birds in each chamber, 118 pair total, were divided into four subgroups and fed a diet containing either 2600, 2800, 3000, or 3200 kcal/kg of metabolizable energy. The energy to protein ratio was held constant at 186. In Period 2, at 63 weeks of age, chambers with the lowest and highest temperatures were changed from 18.3 to 15.6 C and 29.5 to 32.2 C, respectively. Only the lowest and highest energy diets were used. In both periods, the birds kept at higher temperatures and fed the high energy diets consumed significantly less feed (P less than .05) than the other comparable groups. Hatchability was significantly higher (P less than .05) in groups fed the 3000 and 3200 kcal/kg diets as compared to the 2600 kcal/kg diet group. In Period 2, egg production increased in all groups, but birds kept at 32.2 C laid significantly fewer (P less than .05) eggs per bird than those kept at 15.6 and 23.9 C, respectively. The best performance, as measured by salable chicks produced per hen, was obtained in the group kept under a constant temperature of 23.9 C and fed the high energy diet (3200 kcal/kg).