Oviposition and egg quality traits of dwarf and naked neck layers

Oviposition and egg quality traits were studied in dwarf and naked neck layers in Maputo (Mozambique) during a 28-d period at 35 weeks of age. Birds were caged individually in a laying house with natural light and ventilation. Average daylight length during the study was 11.2 hr and minimum and maximum temperature was 19.6 °C and 30.1 °C, respectively. The main results show that the sex-linked dwarfing gene (dw) increased the mean interval and time of oviposition, and reduced the sequence length and rate of lay. A bimodal distribution of oviposition intervals was observed in the dwarf population. No meaningful effect of the naked neck (Na) gene could be seen on oviposition traits. The dw gene also reduced the egg and components weight as well as the height of the albumen. The Na gene was associated with increased yolk weight and reduced albumen height.