Saemi F, Zare Shahneh A, Zhandi M, Akhlaghi A, Ansari Pirsaraei Z
Department of Animal Science, University College of Agriculture and Natural Resources, University of Tehran, 4111, 31587-77871, Karaj, Iran.
Department of Animal Science, University College of Agriculture and Natural Resources, University of Tehran, 4111, 31587-77871, Karaj, Iran.
Anim Reprod Sci. 2018 Nov;198:82-89. doi: 10.1016/j.anireprosci.2018.09.004. Epub 2018 Sep 6.
A hypothesis was tested that long-term administration of thyroxine (T) in broiler breeder hens would affect fertility, sperm penetration rate, and the duration of fertility. Relative abundance of oviductal TGF-β4 and HSP70 mRNA was determined to ascertain whether T treatment affected these genes, and modulated the sustained storage of spermatozoa within the uterovaginal sperm storage tubules of hens. A total of 70, 47-week-old Cobb 500 breeder hens was randomly allotted to two treatment groups (T treatment (ET) and control). The T was orally administered to the ET group (0.3 mg T/bird/day) for 100 consecutive days; whereas the control group was not administered T during the experimental period. Breeder hens were artificially inseminated to evaluate specific reproductive variables. On the last day of the treatment period two hens /replicate were randomly killed to estimate oviductal gene expression. The T treatment resulted in an increase in plasma concentration of T; however, the T concentration was not affected. The long term administration of T had no effect on fertility; however, it resulted in a decreased sperm penetration rate and decreased the duration of fertility compared with the control group. The relative abundance of TGF-β4 and HSP70 mRNA in the SST was not influenced by T supplementation. The correlation coefficients between fertility and sperm penetration rate with relative abundance of TGF-β4 and HSP70 were not significant. Overall, among the diverse reproductive variable assessed in the current study, the sperm penetration rate and the duration of fertility were most responsive to long-term treatment with T.
一项假说得到验证，即长期给肉种鸡母鸡施用甲状腺素（T）会影响其繁殖力、精子穿透率和繁殖力持续时间。测定输卵管TGF-β4和HSP70 mRNA的相对丰度，以确定T处理是否影响这些基因，并调节母鸡子宫阴道精子储存小管内精子的持续储存。总共70只47周龄的科宝500肉种鸡母鸡被随机分配到两个处理组（T处理组（ET）和对照组）。对ET组连续100天口服T（0.3毫克T/只/天）；而对照组在实验期间未施用T。对种鸡进行人工授精以评估特定的生殖变量。在处理期的最后一天，随机宰杀每重复组中的两只母鸡，以估计输卵管基因表达。T处理导致血浆T浓度升高；然而，T浓度不受影响。长期施用T对繁殖力没有影响；然而，与对照组相比，它导致精子穿透率降低和繁殖力持续时间缩短。T补充对SST中TGF-β4和HSP70 mRNA的相对丰度没有影响。繁殖力和精子穿透率与TGF-β4和HSP70相对丰度之间的相关系数不显著。总体而言，在本研究评估的各种生殖变量中，精子穿透率和繁殖力持续时间对长期T处理反应最为敏感。
