Relationship between fertility and fatty acid profile of sperm and eggs in Arctic char, Salvelinus alpinus

This study investigated the relationship between fertility and fatty acid (FA) profiles of egg chorions, total egg, and sperm cells of Arctic char, Salvelinus alpinus (L.) broodstock housed in tanks and fed a commercial diet. Fertility of semen from individual males was assessed using pooled eggs, and vice versa. Fertility of the gametes of broodstock fish was classified according to the percentages of eyed stage embryos into: (a) for males, high, ≥68%, medium: 49–67% and low: ≤48%; (b) for females, high: ≥55%; medium: 28–54% and low: ≤27%. Spermatozoa from the high fertility group contained less short-chain saturated FAs, more n-3 and n-6 FAs with a higher n-3 to n-6 ratio compared to the sperm from the low fertility group. Egg chorions from the high fertility group also had less short-chain saturated FAs compared to the low fertility group. For spermatozoa significant correlations were found between C15:0, total saturated FAs, C22:5n-3, C22:6n-3, total n-3 FAs, and the ratios of n-3 to n-6 and their fertility, but no correlations were found between fatty acid profiles of egg chorions and of total eggs and egg fertility. In conclusion, sperm fertility of Arctic char is influenced to a much higher extent by their fatty acid composition than that of the eggs.