Effects of egg position in artificial incubation of Japanese quail eggs (Coturnix japonica)
Moraes, T G VRomao, J MTeixeira, R S CCardoso, W M
Incubation procedures are important for maintenance and improvement of quail egg production. Many factors can interfere with the success of incubation or the quality of hatched chicks. Thus, the objective of this study was to verify the effects of different positions and turning during artificial incubation of Japanese quail eggs on hatchability, egg weight loss, chick weight, and embryonic mortality. Eighty Japanese quail (Coturnix japonica) were used for egg collection. Six hundred eggs were divided into four experimental groups (n = 150), according to their position during incubation: vertical position with small end up, vertical position with small end down, horizontal position without turning, and horizontal position with turning. Incubation process was done by automatic hatcheries with temperature of 37.5ºC and relative humidity of 60%. All eggs were weighed on their collection day and during incubation period to verify egg weight loss. All quail chicks were weighed at hatch. The eggs incubated in horizontal position with turning had the highest hatchability (77%), while the ones incubated in vertical position with small end up presented the lowest hatchability (8%). Egg position and turning influenced water loss during incubation. The groups with better hatchability presented lower egg weight loss and better hatch weight. The infertility-early embryo death was similar to the late embryo death in the eggs incubated in horizontal position with turning, while in the groups incubated in static position, the late embryo death was higher. The late embryo death was considered the main cause of mortality in the groups incubated in horizontal position without turning (31%), vertical position with small end down (24%) and vertical position with small end up (70%).(AU)
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