Conservation à court terme des gamètes de Salmonidés à des températures voisines de 0 °C

Abstract

Short term preservation of gametes in Salmonids. Preservation of gametes was attempted in two species of salmonids brown trout (Salmo trutta) and rainbow trout (Salmo gairdneri). Tests were carried out with gametes stored at 0°C during 7 days. The following results were obtained : after one day a drop of fertilizability (13 p. 100) was observed for ova in brown trout but not in rainbow trout. However, after 5 days the fertilizability of the female gametes is the same for both species (about 57 p. 100). Ova of brown trout vary more widely in response to aging than those of rainbow trout. The loss of ova fertilizability may be partly compensated by using larger doses of sperm (12.10 6 spermatozoa/egg). Sperm of rainbow trout lose 25 p. 100 of their fertilizing ability after one day and 10 p. 100/day during the following days. There is a significant interaction between aging of sperm and ova which is not of a simple type additif or multiplicatif. Introduction.