Molecular studies on incubation behavior and the application

目前市售的白来客霍恩种鸡不表现出孵化行为，但日本本土种鸡和土耳其鸡仍表现出孵化行为。因此，在这些鸟类中，孵化行为降低了产肉率和产蛋率，给养禽业造成了很大的经济损失。因此，本研究的目的是揭示这些鸟类孵化行为的分子机制，并为消除这些鸟类的孵化行为奠定基础。土耳其鸡和吉弗-吉多里鸡仍有孵化行为。在繁殖周期内，血浆泌乳素（PRL）和垂体PRL mRNA水平在孵化期升高，而在产蛋期较低。这些结果提示PRL可能调节诱导和维持孵育行为。通过垂体细胞浸润培养和细胞培养，我们发现VIP通过cAMP级联诱导垂体内PRL的合成和释放。我们克隆了鸡VIP受体mRNA。有孵育行为表达的白来鸿鸡与无孵育行为表达的白来鸿鸡脑PRL受体mRNA的分布无显著差异。此外，在繁殖周期内，恰伯母鸡脑PRL受体mRNA水平没有变化。本文以夏伯鸡为试验对象，研究了刚孵出的雏鸡脱模对孵化行为的影响。离窝24小时的母鸡再次表现出孵蛋行为，离窝72小时的母鸡没有再表现出孵蛋行为。离巢24和72小时后，所有母鸡血浆PRL水平均下降。这表明可能有其他因素在调节孵育行为的维持。向火鸡和鸡体内注射VIP抗体可显著降低血浆PRL水平，抑制其孵化行为。少

Now commercial White Leghorn strain chicken dose not express incubation behavior, but Japanese native strain chicken and turkey hens still express incubation behavior. Therefore, in these birds, the incubation behavior lowers productivity of meat and egg laying, causing a lot of economic loss in poulty industries. Therefore, the poupose of present study is to reveal molecular mechanism of the incubation behavior and to establish the application for the removal of incubation behavior of these birds.Turkey and Gifu-jidori hens still express incubation behavior. During the reproductive cycle in these birds, levels of plasma prolactin (PRL) and pituitary PRL mRNA increased during the incubation period but these levels were low in the laying period. These results suggest that PRL may regulate induction and maintaining of incubation behavior.Using perifusion culture of the pituitary and cell culture of pituitary cells, we demonstrated that VIP induces PRL synthesis and release in the pituita … More ry gland via cAMP cascade. We cloned chicken VIP receptor mRNA.There were no significant difference in the distribution of brain PRL receptor mRNA between chabohen displaying expression of incubation behavior and White Leghorn hens without expression of incubation behavior. In addition, during reproductive cycle in chabo hen the levels of brain PRL receptor mRNA did not change.Effects of remobal of newly hatched chicks on incubation behavior were studied in the chabo hens. Those hens whose chicks were removed from the nest for 24 hr displayd again incubation behavior but those hens whose chicks were removed from the nest for 72 hr did not show incubation behavior again. The plasma levels of PRL decreased in all hens whose chicks were removed from the nest for 24 and 72hr. This results suggested that other factor may regulate the maintain of incubation behavior.The administrations of VIP antibody into turkey and chicken hens markedly reduced plasma levels of PRL and inhibited incubation behavior. Less