Factors Affecting Reproductive Performance in Farmed Ostriches

Complete egg production data from a pair breeding flock located in South Africa were used to generate annual reproductive records for all hens exposed to breeding. Traits analysed included measures of total egg and chick production and related traits, along with egg and chick weights. Both genetic and non-genetic factors significantly influenced reproductive performance. Seasonal effects, duration of the breeding season, hen age, and individual variation between hens were the key factors affecting total egg production and related measures. Variation between individual males, and their age, was important for traits related to egg fertility. With the exception of measures for clutching behaviour and fertility, which exhibited no additive variation, heritability estimates ranged between 0.07±0.08 to 0.19±0.10 for egg and chick production traits. Heritability estimates were substantially higher for average egg and chick weights (0.43±0.16 to 0.51±0.17). In combination with moderate repeatabilities and high levels of variation, these results indicate that appropriate culling strategies will improve reproductive performance in the current flock. Further, future gains through selection are likely in this species, although standard errors of heritability estimates were high.