Genetic influences on seasonal decline in the fertility of female turkeys.
Daughter-dam pairs of white, large-bodied, turkey breeder hens (108) were reared under similar husbandry conditions, and their egg production and fertility were monitored from the onset of lay for 6 mo. On a monthly basis, percentage fertility was compared by daughter-dam regressions to estimate heritabilities. The heritability estimates were 18.36, and 38%, respectively, for the 2nd, 3rd, and 4th mo of lay; but no estimates could be made for Months 1, 5, or 6. The heritability of percentage fertility for Months 2, 3, and 4 combined was 42%. The proportion of hens that remained above 75% fertility declined each month for both dams and daughters, except in one case. Thus, the seasonal decline in fertility appears to have a genetic component.
Dunnington
E A
EA
Department of Poultry Science, Virginia Polytechnic Institute and State University, Blacksburg 24061-0332.
Van Krey
H P
HP
Hulet
R M
RM
Denbow
D M
DM
D000818:Animals; D001835:Body Weight / Q000235:genetics; D005260:Female; D005298:Fertility / Q000235:genetics*; D010058:Oviposition / Q000235:genetics; D012044:Regression Analysis; D012621:Seasons; D014422:Turkeys / Q000235:genetics / Q000502:physiology*