Publications des agents du Cirad

Cirad

Effects of social interactions on the reproduction of the Nile Tilapia, Oreochromis niloticus : possible application for breeder management

Diaf H., Canonne M., Baroiller J.F.. 2007. In : Camus Emmanuel (ed.), Cardinale Eric (ed.), Dalibard Christophe (ed.), Martinez Dominique (ed.), Renard Jean-François (ed.), Roger François (ed.). Does control of animal infectious risks offer a new international perspective ? : proceedings of the 12th International Conference of the Association of Institutions of Tropical Veterinary Medicine, Montpellier, France, 20-22 August 2007. Montpellier : CIRAD, p. 301-306. International Conference of the Association of Institutions of Tropical Veterinary Medicine. 12, 2007-08-20/2007-08-22, Montpellier (France).

Behaviour and social factors are important for the reproduction of O. niloticus. The influence of social interactions on the fry production was analyzed using a domestic strain. In a first step (S1), females with high and low reproductive potential (HRP and LRP) were detected within a group of breeders. Two groups (G1 and G2) were constituted with a sex ratio of 3 males / 7 females (1:2.3). G1 presented a significant difference in the average spawning rate of HRP and LRP females (3.5 ± 0.58 and 0.33 + 0.58 spawns.female-1 respectively). We then carried out social reorganizations based on the previously established (SI) reproductive potential (RP). Two groups (GA and GB) with FRP (sex ratio: 1:3) and HRP females (sex ratio: 1:4) respectively were constituted using the G1 breeders. These social reorganizations have strongly affected individual RP and the dominance (aggressiveness) of some LRP females. Within GB, the average spawning number decreased from 3.5 ± 0.58 to 0.75 ± 0.96 spawns.female-1. These results suggest a strong influence of behavioural and social components in the RP of breeders. Interestingly, some HRP females retain their high RP following a social reorganization.

Documents associés

Communication de congrès

Agents Cirad, auteurs de cette publication :