Early development and
survival in brown trout (Salmo trutta fario L.): indirect effects of
selection for growth rate and estimation of genetic parameters
M.
Vandeputte, E. Quillet, B. Chevassus-2002
Aquaculture,
204(3-4) : 435-445
Abstract :
Some components of the response to selection for
growth in the PROSPER program on brown trout (Salmo trutta fario L.)
(+30% in three generations) were investigated. A correlated response on
growth during yolk-sac resorption was looked for, and we estimated the
genetic parameters on growth-related traits at the end of endogenous
feeding. For this purpose, a diallel cross between selected and control fish
was designed, including 200 full-sib families (20 males×10 females), each
of them being represented by four individually recorded fish. A
positive-correlated effect of selection was seen on survival and percent
weight gain at swim-up, and a negative one was shown on dry weight and dry
matter content. No effect was seen on final wet weight. A putative
interpretation is that selected individuals have a higher development rate,
inducing a higher consumption of yolk reserves by the end of the experiment,
and therefore, a decrease in wet weight, dry weight and dry matter content.
Significant sire heritabilities were seen for final wet weight and percent
weight gain (hs2=0.28±0.13 in both
cases). For all traits except percent weight gain, maternal effects were
strong, and an important part of them was related to the initial weight of
eggs. Significant dominance effects were reported for wet weight, dry weight
and percent weight gain.
(INRA
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Tel.: +33-1-34-65-23-54; fax: +33-1-34-65-23-90, e-mail :
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