甲状腺激素与山羊绒生长关系的研究

Research of relation between thyroxin and growing cashmere fibre

为探讨甲状腺激素对羊绒生长的影响,挑选12只(平均(15±1.5)月龄、平均活重(33.14±2.29)kg)内蒙古白绒山羊半同胞羯羊,随机分为2组。用外源褪黑激素(MT)调控羊绒生长,通过皮肤组织中脱碘酶(MD)活性变化,研究皮肤组织中甲状腺激素(T3、T4)与绒毛生长的关系。结果表明:1)埋植MT使绒纤维生长率增加(P<0.05),而对粗毛生长率没有影响(P>0.05);2)绒纤维生长率与血浆MT质量浓度有关(P<0.01),而与血浆T3和T4质量浓度无关(P>0.05);3)绒纤维生长率与皮肤组织中Ⅱ型脱碘酶(MDⅡ)活性呈正相关关系(P<0.05),而与Ⅲ型脱碘酶(MDⅢ)无相关关系(P>0.05)。分析试验结果显示,绒纤维在萌发、生长过程中需要更多的三碘甲腺原酸(T3),说明皮肤组织中甲状腺激素(尤其T3)在绒山羊绒纤维萌发和生长过程中具有重要生理意义。

The experiment designed to study the relation of thyroxin to cashmere growth in cashmere goats. Twelve half-sib wethers of Inner Mongolia white cashmere goats, aged （15 ＋ 1.5） months, weighted （33. 14 ± 2.29） kg, were randomly allocated two groups （6 each group）. Exogenous melatonin was supplied by subcutaneous implantation in the experiment group, and the relatioship between cashmere fibre growth rate and thyroxin change was correlated. The results showed that treatment with melatonin significantly increased cashmere fibre growth rate （P 〈 0.0.5）, but guard hair growth rate was not evident （P 〉 0.0.5）. There was a significant correlation between plasma melatonin concentration and cashmere fibre growth rate （P 〈 0.01）, but it was not significant between plasma melatonin concentration and cashmere fibre growth rate （P 〉 0.05）. In addition, there was also a significant positive correlation between cashmere fibre growth rate and monodeiodinase type Ⅱ （MD Ⅱ） activity of skin （ P 〈 0.0.5）, but monodeiodinase type Ⅲ （MDⅢ） activity was not （P 〉 0.0.5）. In conclusion, triiodothyronine （T3） may play important roles in initiating and growing of cashmere fibre in skin of cashmere goats.