The Effect of Dose Rate upon Reproductive Performance of White Leghorn Hens and Their Progeny

Groups of 30 White Leghorn hens were exposed to 800 R (⁶⁰ Co) at each of the following dose rates: 1, 5, 25, or 42 R/min. and compared with 30 hens kept as controls. Reproductive performance was recorded in these hens and their progeny from eggs hatched at varying times after irradiation. Half the surviving hens in each group were exposed to 800 R (25 R/min) 159 days after the first irradiation and egg production recorded for 8 weeks. Egg production was reduced by dose rates varying from 5-42 R/min during the first 5-6 weeks after irradiation. Hatchability of the eggs was reduced during the first 14 days after irradiation at 25 and 42 R/min, but the reproductive performance of the progeny was not altered. The 42 R/min rate given in the first irradiation seemed to have a residual effect on egg production over an 8-week period after the second exposure of 800 R at 25 R/min.