M. Dupontnivet et al., QUANTITATIVE GENETICS OF REPRODUCTIVE TRAITS IN THE EDIBLE SNAIL HELIX-ASPERSA MULLER, The Journal of experimental zoology, 281(3), 1998, pp. 220-227
The present study was carried out to obtain accurate estimates of gene
tic parameters for the following reproductive traits in Helix aspersa:
interval between end of hibernation and mating (R1), interval between
mating and egg-laying (R2), and for each clutch, egg number and mean
egg weight. Genetic correlations with growth traits were also estimate
d. Data from 983 (1780 for R1) animals issued from 123 full-sib famili
es were analyzed. Genetic parameters were estimated with REML method a
pplied to an animal model. Observation of egg number and R1 revealed t
hat some early adult animals (snails with reflected peristome) were no
t entirely sexually mature. Heritabilities were low or medium: 0.12 +/
- 0.01 for egg number; 0.37 +/- 0.01 for mean egg weight; 0.21 +/- 0.0
1 for R1, and 0.15 +/- 0.01 for R2. Genetic correlations were favourab
le to selection for improving adult weight because egg number and mean
egg weight were positively correlated with adult weight. (C) 1998 Wil
ey-Liss, Inc.