Influence of Age of Parents on Fertility and Hatchability in the Rhode Island Red

Several studies have been published on the influence of hen's age on fertility and hatchability (see review by Landauer, 1961; Goodwin et al., 1964). In general, hatchability of the dam has been found to decrease from the first laying year to the second. Reports on the effects of the age of the sire on hatchability are conflicting. Hays and Talmadge (1949) observed a depression in hatchability of eggs from matings of males used in successive years while Baranovskaja (1957) failed to detect any direct relationship between age of sires and hatchability of their mates’ eggs. Fertility however is known to be depressed with increasing age of both sire and dam (Curtis and Lambert, 1929; Jull, 1935). Thus while there is ample evidence for maternal effects on fertility and hatchability and sire's effect on fertility, it is not known whether these effects are additive or whether there is interaction between such . . .