In salmonids, exposure to elevated temperature impairs oogenesis. As such, there is a need to understand the molecular mechanisms that underpin this process, and develop mitigation strategies that maintain or rescue reproductive development in broodstock. In this study, follicle stimulating hormone (Fsh) and/or insulin-like growth factor 1 (Igf1) treatment were assessed for their ability to promote reproductive function at 14 and 22 °C in ovarian follicles from coho salmon in vitro. Maintenance at 22 °C resulted in the downregulation of fsh receptor, 17α-hydroxylase/C17,20-lyase and p450 aromatase a (cyp19a1a), and connexin 34.3 (cx34.3). While combined treatment with Fsh and Igf1 stimulated the expression of cyp19a1a at 14 °C, this treatment was not effective at 22 °C. Upregulation of cx34.3 occurred in response to treatments that contained Igf1 regardless of temperature, and there is evidence to suggest that apoptosis was inhibited to some extent at 22 °C following combined treatment with Fsh and Igf1. This study demonstrates the thermal impairment of key reproductive genes, and highlights the potential for novel hormone treatments to rescue oogenesis in salmonids.

Item Type:	Refereed Article
Keywords:	ovarian steroidogenesis, atresia, apoptosis, climate change, hormonal rescue, fish biology, reproductive biology, oocyte
Research Division:	Agricultural, Veterinary and Food Sciences
Research Group:	Fisheries sciences
Research Field:	Fish physiology and genetics
Objective Division:	Animal Production and Animal Primary Products
Objective Group:	Fisheries - aquaculture
Objective Field:	Aquaculture fin fish (excl. tuna)
UTAS Author:	Anderson, K (Dr Kelli Anderson)
ID Code:	131508
Year Published:	2019
Web of Science® Times Cited:	5
Deposited By:	Fisheries and Aquaculture
Deposited On:	2019-03-20
Last Modified:	2020-01-14
Downloads:	0