Normal tables provide an objective step-wise description of the morphological development of an embryo. Such tables have been described for the chicken, turkey, quail, and duck embryos, but there is no such staging table for goose embryos. As the goose has one of the longest incubation periods of all the poultry species and embryo mortality during incubation is relatively high, a normal table of goose embryo development would be useful in assessing the morpho-genetic status of the goose embryo before and during incubation. In this study, embryos were isolated from commercial White Koluda goose eggs stored no longer than four days in a cool room (18°C) prior to incubation and after 4, 8, 12, and 16 h of incubation. Embryo staging was based on the normal tables described for the chicken by Eyal-Giladi and Kochav (EGK) and Hamburger and Hamilton (HH). Goose embryos from unincubated eggs were at Stage X and XI EGK and after 16 h of incubation the majority of embryos were between Stages 2 and 4 HH. Our results suggest that while the stage of development of the embryo in the unincubated goose egg is similar to that reported for the chicken, although the diameter of goose embryo is slighter larger. Following incubation, a goose embryo advances more slowly than a chicken embryo up to 16 h of incubation.
Birds obtained by embryo engineering are used to study embryo development and to produce transgenic birds. As this method of producing birds still generate strong emotions of the public opinion head ornaments, testes and semen characteristics of sex chimera roosters were examined to check whether they differ from chickens obtained by non-manipulated methods. Measurements of head ornaments, testes and semen were correlated with each other. Semen quality factor (SQF) was calculated, as well as the level of fluctuating asymmetry (FA) of bilateral traits (wattles and testes). Positive correlation was found for comb width and wattle length and comb thickness and sperm concentration. Semen characteristics and FA did not exceed the level encounter in other chicken lines. Results obtained indicate that germline chimeras are similar in appearance of secondary sexual traits, and semen and testes characteristics to chickens produced in non-manipulated way.
it is widely practiced that before mating the roosters are selected as reproducers mainly on the basis of head ornaments appearance. relationship between males secondary sexual traits (comb and wattles) with testes size, as all of them are testosterone-dependent traits, were examined. measurements of head ornaments and testes from two broiler breeder lines and two laying lines of chicken were correlated. The value of fluctuating asymmetry (FA) of bilateral traits was also measured. positive correlations were found for head ornaments and testes weight in one of broiler breeder lines. no correlations were found for males of laying lines. the degree of fa did not differ between lines, except for FA of wattle length, which was higher (P≤0.05) for one of the broiler lines. Results obtained indicated that head ornaments cannot be used as the only criterion for rooster selection as reproducers.
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