卵生动物

鸟是卵生动物。

Birds come from eggs .

卵黄蛋白原（Vitellogenin，Vg）是卵生动物中卵黄蛋白的前体，它是受激素调控的一种大分子磷脂糖蛋白。

Vitellogenin ( Vg ) is the egg yolk protein precursor in all egg-laying animals .

对于卵生动物来说，卵黄物质的形成与积累是卵子发生过程中的重要事件。

For oviparous animals , yolk formation and accumulation are the important events in the process of oogenesis .

在卵生动物中，雌性个体生殖细胞不仅为子代提供遗传物质基础，还必须为受精卵的进一步发育提供营养物质。

Besides providing genetic substance for filial generations , germ cells of the female individuals provide nutrient substance for the development of spermoviums in the oviparous animals .

家禽属卵生动物，胚胎发育容易受到外界环境因素（营养、孵化温度、激素和运动等）的影响，其中孵化温度对禽类胚胎发育和机体代谢影响较大。

As the oviparous , Poultry embryonic development is susceptible to external environmental factors , including nutrition , incubation temperature , hormones and exercise , in particular the incubation temperature has great impact on poultry embryonic development and metabolism .

鸟类、鱼和两栖类是卵生的动物。

Birds , fish , and amphibians are " oviparious " .

卵黄磷蛋白是所有卵生雌性动物卵黄的主要成分。

Vitellin is the major constituents of the yolk protein .

雌性蛋白包括卵黄蛋白和卵黄蛋白原，是卵生类动物早期生命阶段中主要的营养物质来源。

Female specific proteins , containing vitellin ( Vn ) and vitellogenin ( Vg ), are main nutrition resource in early stage of life for oviparous animals .

北草蜥（Takydromusseptentrionalis）是中国特有的卵生蜥蜴科动物，在大陆有广泛的分布范围。

The northern grass lizard ( Takydromus septentrionalis ) is an oviparous lacertid lizard that is endemic to China and widely distributed in southeastern part of the country .

鸟类、鱼和栖类是“卵生”的动物

Birds , fish , and amphibians are " oviparous "