Effect of seawater temperature and pH on the sperm motility of the European eel.

The current climate change situation could bring critical effects for marine species, especially those already considered endangered. Although some species can adapt fast to the environmental changes, it is necessary to get into the worst scenario and develop tools to anticipatedly assess the physiological effects of such environmental change. With this purpose, our study aims to determine the effect of a range of seawater temperatures and pHs on sperm motility in the European eel (Anguilla anguilla).

Lipid and fatty acid composition of muscle, liver, ovary, and peritoneal fat in wild flathead grey mullet (Mugil cephalus) according to ovarian development.

Wild adult females of a low trophic omnivore teleost species, the flathead grey mullet (Mugil cephalus), caught in the western Mediterranean were sampled. The lipid and fatty acid composition of ovaries, liver, muscle, and peritoneal fat were analysed at previtellogenesis, early-vitellogenesis -first observed at mid-summer (early August)-, late-vitellogenesis, and the post-spawning period -from mid-September to mid-October-. During ovarian development, the lipid content of muscle was low and constant (3.

Low sperm to egg ratio required for successful fertilization in a pair-spawning teleost, Senegalese sole ().

Cultured Senegalese sole () breeders fail to spawn fertilized eggs. The implantation of large-scale fertilization protocols, to solve this problem, has been frustrated by low production of poor quality sperm. Cultured females were induced to ovulate with a 5 µg kg single injection of gonadotropin-releasing hormone agonist (GnRHa) and viable eggs (82.