ISSN:
1439-0426
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
,
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Survival rate, sex ratio and zootechnical performances were evaluated on 168 kg of Anguilla anguilla elvers (0.45 g) weaned into three groups (A1, A2, A3) at initial densities of 800, 1600 and 3200 g m−3, respectively. In order not to modify the sex ratio, animals weaned at the different densities were maintained separately during the trials, and no size grading was performed at the fattening phase.Final mean weight achieved by females belonging to the different groups showed no statistically significant differences; weight of males was higher (P 〈 0.05) in A1 than in A3 where a higher percentage of males was observed. Sex ratio of eels was different among the groups, with a higher percentage of males in A3 (96%) than in A2 (78%) or in A1 (69%). This finding testifies to a sex differentiation strongly affected by pre-fattening stocking density of elvers. Final load showed an increase in males corresponding to a significantly reduced biomass between A1 and A2 (10.97 and 10.24 kg m−3) and A3 (8.44 kg m−3). Final survival rate ranged from 87% (A1) to 90% (A3). As to food conversion, a better rate was found in A1 (1.9:1) compared to A2 (2.1:1) and A3 (2.3:1) eels.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1439-0426.1997.tb00112.x
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