@INRAE Mathilde Dupont-Nivet (Truites arc-en-ciel)

Publication Evolutionary Applications (Paul et al., 2021)

Between positive impact and negative consequences, the complex effects of inbreeing on the reproduction of the rainbow trout

Through the genetic improvement of the rainbow trout, the efficiency of trout production over the last thirty years has increased notably. But this selection has also contributed to an increase in inbreeding, menacing genetic progress on the long term and the adaptation of populations to a changing environment. That is why scientists from the GABI unit sought to evaluate the effects of inbreeding on the reproductive performances of the rainbow trout.

In an article published in Evolutionary Applications (Paul et al., 2021), scientists from the GABI unit for the first time evaluated the exact effects of inbreeding accumulated locally and over time in a fish genome. To do this, size and reproductive performances of more than 1300 trout from a commercial population selected over 9 generations were analyzed. This study showed that local genomic inbreeding can have important effects, both positive and negative, on performances, without necessarily observing an inbreeding effect on the genome level.

As indicated in the litterature, the main phenomenon observed is inbreeding depression, that is a negative impact of a recent inbreeding explained by accumulation of deleterious recessive alleles at the homozygous state. However inbreeding, in particular that accumulated over past generations, also has positive effects on the reproductive performances of trout.

This study is the first step towards a precise management of matings between reproducers. The use of local inbreeding genomic indicators will allow breeders to better manage the trade-offs between genetic values of breeding stock and the undesirable effects of inbreeding on their offspring.

Contact :

  • Katy Paul (katy.paul@inrae.fr)
  • Florence Phocas (florence.phocas@inrae.fr)

See also

Reference:
Paul, K., D'Ambrosio, J., Phocas, F. (2021). Temporal and region-specific variations in genome-wide inbreeding effects on female size and reproduction traits of rainbow trout. Evolutionary Applications, special issue original article, on line October 2021

Modification date : 05 October 2023 | Publication date : 29 October 2021 | Redactor : K. Paul & al. - Edition P. Huan - Translation W. Brand-Williams