Genetic research on ostrich reproduction so far mostly centred around the estimation of genetic parameters for quantitative traits, like egg production and chick production (Cloete et al., 2008b). Although hatchability has received some attention, component traits like the fertility of eggs and the survival of embryos have largely be ignored, as acknowledged by Cloete et al. (2008b). This part of the thesis seeks to address this shortcoming, by focusing on the following aspects:
Systematic factors that affect ostrich egg incubation traits
To determine genetic parameters for ostrich incubation traits in South Africa
The genetic relationships between water loss and shell deaths in ostrich eggs, assessed as traits of the dam
Heritability of shell-deaths in ostrich eggs and factors affecting hatching failure of fertile eggs during artificial incubation
Genetic (co)variances between water loss and shell-deaths in ostrich eggs Genetic parameters for eggshell traits in ostriches
Effect of female age and genotype on eggshell quality in eggs of females ostriches
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