Akhtar M S, Ciji A, Sarma D, Rajesh M, Kamalam B S, Sharma P, Singh A K
ICAR-Directorate of Coldwater Fisheries Research, Anusandhan Bhawan, Bhimtal 263136, Uttarakhand, India.
ICAR-Directorate of Coldwater Fisheries Research, Anusandhan Bhawan, Bhimtal 263136, Uttarakhand, India.
Anim Reprod Sci. 2017 Jul;182:95-103. doi: 10.1016/j.anireprosci.2017.05.004. Epub 2017 May 18.
The present study was undertaken to gain insight on the physiological basis underlying the constraints in attaining maturity of endangered golden mahseer (Tor putitora) in captivity. Selected hormone levels and stress biomarkers were analysed in wild and captive reared brooders to address the above objectives. As compared to their captive counterparts, plasma 17β-estradiol was significantly (p<0.05) higher in wild caught females. A concurrent trend was observed for plasma vitellogenin, aromatase, 17α, 20β-dihydroxy progesterone (17α, 20β DHP), luteinizing hormone (LH) and11-ketotestosterone (11-KT) indicating a weak hormone response in captive females that potentially hindered maturity. To the contrary, the plasma11-KT levels were not significantly different between wild and captive males. Plasma 17α, 20β DHP level was found significantly (p<0.05) higher in wild caught females compared to females reared in captivity. However, both males of wild and captivity registered significantly higher 17α, 20β DHP than captive females. Plasma 11-KT level was significantly higher in males compared to females. However, the captive females had higher level of 11-KT than captive males. Stress biomarkers viz., cortisol, superoxide dismutase (SOD) and glutathione peroxidase (GPx) were also estimated both in wild and captive brooders. There was no significant difference in plasma cortisol levels of wild and captive reared brooders. However, plasma GPx and SOD activity were significantly higher in captive reared T. putitora as compared to wild brooders counterpart manifesting prevailing oxidative stress in captivity. Overall results showed endocrine and stress differences between wild and captive reared brood fishes during early spawning period which highlighted the endocrine failure of female reproductive maturity in captivity.
本研究旨在深入了解圈养濒危金色马哈鱼（Tor putitora）成熟受限的生理基础。分析了野生和圈养亲鱼的选定激素水平和应激生物标志物，以实现上述目标。与圈养的同类相比，野生捕获的雌性血浆17β-雌二醇显著更高（p<0.05）。血浆卵黄蛋白原、芳香化酶、17α，20β-二羟基孕酮（17α，20β DHP）、促黄体生成素（LH）和11-酮睾酮（11-KT）呈现出一致趋势，表明圈养雌性的激素反应较弱，这可能阻碍了其成熟。相反，野生和圈养雄性的血浆11-KT水平没有显著差异。发现野生捕获的雌性血浆17α，20β DHP水平显著高于圈养雌性（p<0.05）。然而，野生和圈养的雄性17α，20β DHP均显著高于圈养雌性。雄性的血浆11-KT水平显著高于雌性。然而，圈养雌性的11-KT水平高于圈养雄性。还对野生和圈养亲鱼的应激生物标志物，即皮质醇、超氧化物歧化酶（SOD）和谷胱甘肽过氧化物酶（GPx）进行了评估。野生和圈养亲鱼的血浆皮质醇水平没有显著差异。然而，圈养的金色马哈鱼血浆GPx和SOD活性显著高于野生亲鱼，表明圈养中普遍存在氧化应激。总体结果表明，野生和圈养亲鱼在早期产卵期存在内分泌和应激差异，这突出了圈养中雌性生殖成熟的内分泌功能障碍。
