english
français
RP2E INRA Université de Lorraine

Comparison of oogenesis progress and egg quality in domesticated and wild Eurasian perch females under photothermal treatment

Séminaire ELSEVIER : "Aquaculture", 24-27 août, Montpellier, France

Khendek, A., Milla, S., Alix, M., Personne, A., Ledore, Y., Viot, S., Rousseau, C., Fontaine, P.

2015

In aquaculture species, domestication process is accompanied with acclimation and adaptation to captive conditions. It induces changes at anatomical, physiological and molecular levels thereby affecting a variety of biological functions. While there is abundant literature on the domestication effects on growth and stress the effect on reproduction has received limited attention. Still, some differences between the fish families seem to exist. In this work, we investigated the domestication effect on reproductive ability of Eurasian perch (Perca fluviatilis L.) a promising candidate for the development of European aquaculture and whose response to domestication has not been questioned yet.

To address this question, two populations of wild and domesticated females originated from Geneva lake were reared under controlled conditions and submitted to a photothermal program to control reproduction. Breeders were sampled four times during the photothermal treatment. At each time morphological parameters, GnRH and gonadotropins gene expression, sexual steroids, vitellogenin and oocyte developmental stages were investigated for both populations. Finally, the reproductive success was evaluated for both populations.

Gonado-somatic index, 17 ?-estradiol levels and oocyte diameter were significantly higher in domesticated population than in wild one. In contrast, hepato-somatic index, testosterone,11-ketotestosterone, and alkaline-labile phosphate  levels were found to be higher in wild females than in their domesticated counterpart.

 A lower development rate of eggs was observed in domesticated population by comparison with the wild one even if malformations were higher in domesticated population (43±0%)  than  in wild one  (16±8%). Larval survival was also markedly higher in wild population (37±2%) than (2±2%) in the domesticated one only.

In conclusion, these results show that in this example of domestication process, a positive effect of domestication on oogenesis progress was pointed out while it negatively affects the quality of eggs and larval survival.

Imprimer le document