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Modification of population sex ratios by domestication and artificial selection in the European sea bass (Dicentrarchus labrax L.)

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HAL Id: hal-01019743

https://hal.archives-ouvertes.fr/hal-01019743

Submitted on 5 Jun 2020

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Modification of population sex ratios by domestication and artificial selection in the European sea bass

(Dicentrarchus labrax L.)

Marc Vandeputte, Mathilde Dupont-Nivet, Pierrick Haffray, H Chavanne, A. Vergnet, B. Chatain

To cite this version:

Marc Vandeputte, Mathilde Dupont-Nivet, Pierrick Haffray, H Chavanne, A. Vergnet, et al.. Mod-ification of population sex ratios by domestication and artificial selection in the European sea bass (Dicentrarchus labrax L.). Colloque de la Société Française de Génétique ”Genetics, Epigenetics and Evolution of Sex Chromosomes”, Jun 2011, Paris, France. pp.Poster. �hal-01019743�

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Material and methods

Introduction

Vandeputte, M.

1,2

, Dupont-Nivet, M.

1

, Haffray, P.

3

, Cha

I1INRA, UMR1313 GABI, Domaine de Vilvert, 78350 Jouy en Josa

Palavas les Flots, France, 3Sysaaf, Campus de Beaulieu, 35000 R

Emplacement photo  qualité 150dpi minimum Emplacement photo  qualité 150dpi minimum Emplacement photo  qualité 150dpi minimum

Modification of population sex ratio

selection for growth in the Europea

In the European sea bass, the sex-ratio of farm male-biased (> 75%), while wild populations se ratio. Females are preferred by farmers due to The situation in farmed populations is known larval rearing temperature, but also to genetic polygenic, and linked with growth rate. We tes and phenotypic selection for growth on popula genetics framework where phenotypic sex is m an underlying liability called “sex tendency” genetic and environmental effects.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 Mâles Fe m elle s 33 wild ♂ (W) 23 wild ♀ G0 G1 n=5915 longueur Selection threshold

12

e

Séminaire des thésards du Départemen

INSTITUT NATIONAL DE LA RECHERCHE AGRONOMIQUE / Ifremer GDR Amélioration génétique pour une Pisciculture Durable

Chemin de Maguelone, 34250 Palavas-les-Flots

Tél : +33(4) 67 13 04 07 • Courriel : marc.vandeputte@jouy.inra.fr

Results

« Genetics, Epigenetics and Evolution of

G2

13 femelles

20 mâles Sauvages

20 mâles

Domest. (G1) 20 mâles Massal

1. 18.2% females in G1, h²=0.62 for sex tendency, h²=0 body length, rA=0.48

2. Body weight in G2: S>D=W, +15 à 20% for S

3. Sex-ratio in G2: S 58.4%♀, D 47.1%♀, W 41.4%♀ (P<0. 4. High genetic correlation between body length at 90 da sex tendency (fig2)

5. Simulation: 75% females in G10 if the 5% largest fi selected at each generation (fig3). If those G10 fish were in conditions mimicking the natural ones, 95% females be expected

Conclusions

1. Selection for body length induces a correlated res on sex-ratio

2. Early growth (90 dpf) is more tightly genetically linked tendency than late growth

3. Combining selection for growth and manipulati environmental conditions should allow the product quasi-monosex populations of sea bass for aquaculture.

n=1098

avanne, H.

4

, Vergnet, A.

2

, Quillet, E.

1

and Chatain, B.

2

as, France, 2Ifremer UMR110 INTREPID, Chemin de Maguelone, 34250

Rennes, France, 4ISILS, Localita la Quercia, 26027 Rivolta d Adda, Italy

os by domestication and artificial

n sea bass (Dicentrarchus labrax L.)

med populations is usually highly eem to conform to a 50/50 sex better growth and later puberty. to be linked to larval and post-c fapost-ctors whipost-ch are presumably sted the impact of domestication ation sex-ratio, in a quantitative modeled as a threshold trait with ”, which is influenced both by

1.Factorial mating design with 33 wild G0♂ (W), 23 W♀ 7000 offspring individually tagged at 35 g (1 year), parentage assignment by genotyping of microsatellites(>98%), phenotyping of G1 at 400g (2 yrs) for sex & growth

2. Estimation of genetic parameters of growth & sex (h2, r

A) in

G1 fish by covariance between relatives (REML)

3. experimental selection for growth on G1 fish, P=5% on body length (BL)Î20 S males, + 20 males with average body length (D= domesticated)

4. Evaluation of response to selection and domestication on body weight and sex-ratio (20 W D and S males mated to 13

Figure 1:  The threshold model for sex‐ratio  in sea bass, with the phenotypic effect of early rearing environment in farms. 20%F 80% M sex tendency male-female threshold 50% F 50%M in the wild captive

nt de Génétique Animale Pornichet, 6 & 7 avril 2010

body weight and sex ratio (20 W, D and S males mated to 13 standard wild females)

5. Stochastic simulation study of selection on body length (quantitative genetics framework, h²=0.41 for body length, 0.62 for sex tendency, genetic correlation = 0.48) & estimation of the correlated response on sex-ratio.

f Sex Chromosomes », Paris, 9-10 June 2011

0.41 for .001) ays and ish are reared would sponse d to sex ion of tion of Figure 2: genetic correlation  rA  (± s.e.) between body length  and the liability trait sex  tendency at different ages in dpf  (days post‐fertilisation). Acknowledgements

This work was conducted in the frame of two European projects, Heritabolum (Q5CR‐2002‐71720) and Competus (COOP‐CT‐2005‐017633). It is also part of the work programme of the INRA‐Ifremer Research Group on Sustainable Fish Breeding.

Figure 3: Simulated co‐ evolution of body length  and sex‐ratio in a  population of sea bass  submitted to phenotypic  selection on body length  with a proportion  selected of 5% at each  generation 0 0.2 0.4 0.6 0.8 1 0 200 400 600 800 r A Age (dpf) 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 150 200 250 300 350 400 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 P ropor ti on  of  fe m al e s Bo d le n gth  (mm) Generations

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