Development of Birds

Incubation during the Egg-Laying Period in Relation to Clutch-Size and Other Aspects of Reproduction in the Great Tit Parus major

“…Admittedly, the exact temperature threshold value for tits is still unknown, but it is probably fairly similar to that known for the Domestic Fowl (about 24-27'C; Stresemann 1934, Funk and Biellier 1944, Harrison and Klein 1954in Bellairs 1960, see also Drent 1975). As shown in Tabs 2-3, and illustrated in Fig.…”

Determination of 4,4‘-Dinitrocarbanilide (DNC), a Component of Nicarbazin, in Canada Goose (Branta canadensis) Eggshells Using High-Performance Liquid Chromatography

“…In poultry, DNC is observed to accumulate in the liver and kidneys preferentially to the muscle, skin, and fat (23). We associate the accumulation of the DNC in the eggshell with the waste accumulation functions accorded to the eggshell membranes as the embryo develops (11), with the understanding that there may be active transport of the DNC required for this to occur.…”

“…In the chicken egg, the CAM is completely formed by the 14th day after fertilization, prior to organogenesis (12). The CAM becomes highly vascularized and is associated with gas exhange, waste excretion, and calcium mobilization for the developing embryo (11,12).…”

“…The eggshell is a complex structure consisting of both calcified and uncalcified layers (10)(11)(12). There are two noncalcified membranes associated with the shell in the early stages of embryo development, the outer shell membrane and the inner shell membrane (10)(11)(12).…”

“…There are two noncalcified membranes associated with the shell in the early stages of embryo development, the outer shell membrane and the inner shell membrane (10)(11)(12). As the embryo develops, another membrane, the chorioallantoic membrane (CAM), is formed.…”