Boosting the reproductive performance of Arctic charr using high-throughput sequencing technologies

Arctic charr Salvelinus alpinus is the second most farmed fish in Sweden, but its yield is affected by the low reproductive performance when cultivated. The fertilization success depends considerably on the contribution of males.

It was shown that the cultivation results in lower sperm quality in Arctic charr males, thereby reducing the number of fertilized eggs and hatched embryos. However, the factors that affect sperm qualities remain to be investigated.

This project aims to explore multiple parameters that affect sperm quality as possible explanations for the low reproductive performance of farmed Arctic charr.

First, I will assess the impact of age on male fertility by using complete sperm-quality records for males from their first spawning until they are used in reproduction. Then, I will evaluate sperm quality changes across the whole spawning season.

These will allow me to reveal exactly when sperm have the highest quality and when it drops in response to aging or spawning time. Next, I will highlight the genetic variants across the whole genome that contribute to fertility.

Finally, by studying transcriptome profiles, I will investigate the information that sperm delivers to offspring to determine the effect of sperm quality on progeny development.

The project will be the first to provide a comprehensive understanding of the factors that impair the reproductive performance in farmed Arctic charr.It will contribute to the increase in Arctic charr production in Sweden.