Lien R J, Siopes T D
Department of Poultry Science, North Carolina State University, Raleigh 27695-7608.
Poult Sci. 1989 Aug;68(8):1126-32. doi: 10.3382/ps.0681126.
Turkey hens were thyroidectomized at different ages and phases of their reproductive cycles. Egg production, primary remige molting, and plasma thyroxine (T4) and triiodothyronine (T3) concentrations were monitored during each of three experiments. Thyroidectomy of hens (26 and 30 wk of age) prior to photoinduction of egg production prevented subsequent egg production and molting. Thyroidectomy of adult hens (36 wk of age) early in the egg production cycle caused a gradual termination of egg laying without the occurrence of molting. Thyroidectomy of mature hens (66 wk of age) during the light restriction period prior to their second egg production cycle prevented subsequent egg laying and molting. All successful thyroidectomies reduced plasma T4 and T3 to concentrations below the sensitivity levels of the assays. Feeding 1 ppm T4 to thyroidectomized hens resulted in resumption of normal egg production and molting. These results indicate that the thyroid is essential for the initiation and maintenance of egg production and for molting in turkey hens.
在火鸡母鸡生殖周期的不同年龄和阶段对其进行甲状腺切除。在三个实验的每个实验过程中，监测产蛋量、初级飞羽换羽情况以及血浆甲状腺素（T4）和三碘甲状腺原氨酸（T3）的浓度。在光诱导产蛋前对母鸡（26周龄和30周龄）进行甲状腺切除可阻止随后的产蛋和换羽。在产蛋周期早期对成年母鸡（36周龄）进行甲状腺切除会导致产蛋逐渐终止且不发生换羽。在第二个产蛋周期前的光照限制期对成熟母鸡（66周龄）进行甲状腺切除可阻止随后的产蛋和换羽。所有成功的甲状腺切除均使血浆T4和T3浓度降至检测灵敏度水平以下。给甲状腺切除的母鸡饲喂1 ppm的T4可导致产蛋和换羽恢复正常。这些结果表明，甲状腺对于火鸡母鸡产蛋的启动和维持以及换羽至关重要。
