Abstract
Examination of goose eggs revealed the dependence of embryonic development of goslings on egg parameters: for example, extension of holding period from 7–8 to 13–14 days increased the loss of embryos with underdeveloped circulatory system in the form of “blood ring” from 7.7 to 9.4% and, in the form of “frozen” and “late dead", from 5.9 to 11.9%. This reduced the output of healthy goslings from 62.9 to 51.7%, with an increase in weak and underdeveloped goslings from 5.1 to 7.5%. Embryo losses in the form of “blood ring” of the eggs of mean weight (140–150 g) were 4.6% less than those of small eggs, and 9.1% less than large eggs, which indicates a higher output of goslings from eggs of mean weights. The hatchability and sex of growing geese, as affected by hatching egg holding period, weight, shape and density were investigated. The optimal holding period for hatching eggs of geese in order to obtain maximum growing bird hatchability was determined. An increase in weight and shape index of hatching eggs decreased the hatchability percentage of geese, and increased the density of eggs increased the growing bird hatchability. The effect of pre-brooding holding period, weight parameters, shape and density of hatching eggs of geese on the ratio of growing birds’ sex (female/male) was confirmed. An increase in sex differentiation of one-day-old goslings with increasing egg holding period was also identified: the maximum female/male ratio was 0.90/1.12 with a holding period of 13–14 days.