Abstract Incubation length and hatching asynchrony are integral elements of the evolved reproductive strategies birds. We examined intra- interpopulation variation in both traits for Eastern Kingbird (Tyrannus tyrannus) populations from New York (NY), Kansas (KS), Oregon (OR) found that incubation were not repeatable among females, after controlling a trait, clutch size. Instead, size influence...

Due to its central position in the production chain, in-ovo development is influenced by pre-incubation factors that affect the quality of embryonated eggs and incubation conditions themselves, and both may influence egg hatchability and chick quality, as well as bird survival, growth performance, and phenotype in the field. The evolution of the incubation process over the years is characterize...

Incubation starts during egg laying for many bird species and causes developmental asynchrony within clutches. Faster development of late-laid eggs can help reduce developmental differences and synchronize hatching, which is important for precocial species whose young must leave the nest soon after hatching. In this study, we examined the effect of egg laying sequence on length of the incubatio...

Five experiments involving 3,100 settable eggs with living embryos of commercial broiler parent stock were conducted to determine the effect of ascorbic acid (AA) and cooling during egg incubation on embryonic weight, hatchability, percentage of cull chicks, embryonic mortality, and body weights of the hatched chicks. The treatments were carried out at 15, 15, 17, 11 and 19 d of incubation for ...

Understanding intrinsic (physiological) and extrinsic (e.g., temperature) causes of variation in embryonic development time (incubation period) is important because they can have different impacts on individual quality. Robert Ricklefs and colleagues have argued that longer incubation periods result primarily from intrinsic physiological programs that increase individual quality and adult survi...

This study aimed to evaluate the effects of water temperature during fertilization and egg incubation in the determination of the sex ratio of fingerlings of silver catfish Rhamdia quelen. Water temperatures of 19, 25 and 30°C were used during the egg fertilizations, and the eggs were then incubated at temperatures of 19, 25 or 30°C for each fertilization temperature condition. An increase in t...

The present study was carried out to determine the sex of the fertilized white layer eggs with using morphological measurements. A total of 300 Super Nick White Layer (54 wks of age) eggs were incubated and sexed in the end of incubation period. Before incubation egg length, width and weight were measured. The egg volume and shape index were estimated with using these measurements for each egg....

Four thousands and two hundred hatching eggs were obtained from Bandarah chicken to evaluate the effect of chemical and natural eggs disinfectants and fumigation on egg weight loss, embryonic mortality, hatchability, hatch time, chick weight, and chick weight loss. Three incubation trials were done, each one contained 1400 hatched eggs and divided into fourteen treatments (100 eggs per each). F...

Varied egg incubation temperatures can result in immediate effects on the phenotype of reptiles, and also latent effects that can augment or contradict effects evident at egg hatching. I examined the effects of incubation temperature on embryonic development, hatching morphology, and subsequent growth in multiple populations of the lizard Anolis carolinensis. Eggs from wild-caught females in fo...