Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan; Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan.
Laboratory of Veterinary Physiology, Department of Veterinary Medicine, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan; Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan.
Gen Comp Endocrinol. 2019 Aug 1;279:148-153. doi: 10.1016/j.ygcen.2019.03.009. Epub 2019 Mar 18.
High temperature decreases the egg number, ovarian weight, and hierarchical follicle number. In the present study, we investigated the effect of high temperature on the quality of eggs of adult female quails. Laying quail were raised under a standard thermal condition of 25 °C until exposed to an elevated temperature of 34 °C (experimental) or maintained at 25 °C (control) from 12:00 to 16:00 for 10 consecutive days. Weight and number of eggs were measured; serum and the largest follicles were collected and used for hormone measurement. Ovaries and adrenals were collected for expression analysis of 3β- and 17β-HSD, genes encoding steroidogenic enzymes. Egg weight slightly decreased with an increase in the treatment time in the heat-challenged group; the egg weight significantly decreased in the heat treatment group than in the control group during the last 2 days of experiment (P < 0.05). The laying rate showed no difference during the experimental period but significantly decreased on the last day in the heat treatment group. In the experimental group the ovaries and oviducts were lighter (P < 0.05) and the hierarchical follicle number and ovarian weight decreased (P < 0.05) compared to the control group. Although serum corticosterone level significantly increased after heat challenge (P < 0.05) and immediately recovered to the normal level, yolk immunoreactive corticosterone in the hierarchical follicle (F1, F2, F3) significantly increased (P < 0.05). The expression level of 17β-HSD showed no changes in the ovary but significantly increased in adrenals (P < 0.05). Our findings indicate that the effects of heat challenge on the maternal ovary in the quail are mediated through the adrenal function.
高温会降低鸡蛋数量、卵巢重量和等级卵泡数量。本研究旨在探讨高温对成年鹌鹑母鸡蛋品质的影响。产蛋鹌鹑在 25°C 的标准热条件下饲养，直到从 12:00 到 16:00 连续 10 天暴露在 34°C 的高温（实验组）或维持在 25°C（对照组）。测量蛋重和蛋数；采集血清和最大卵泡，用于激素测定。收集卵巢和肾上腺，用于分析编码类固醇生成酶的 3β-和 17β-HSD 基因的表达。随着热应激组处理时间的增加，蛋重略有下降；在实验的最后 2 天，热处理组的蛋重明显低于对照组（P<0.05）。在实验期间，产卵率没有差异，但在热处理组的最后一天显著下降。与对照组相比，实验组的卵巢和输卵管较轻（P<0.05），等级卵泡数和卵巢重量减少（P<0.05）。尽管热应激后血清皮质酮水平显著升高（P<0.05），但立即恢复到正常水平，但在等级卵泡（F1、F2、F3）中卵黄免疫反应性皮质酮显著增加（P<0.05）。卵巢中 17β-HSD 的表达水平没有变化，但肾上腺中显著增加（P<0.05）。我们的研究结果表明，热应激对鹌鹑母体内卵巢的影响是通过肾上腺功能介导的。
