Relationships between morphometric characteristics of brackishwater prawn, Macrobrachium macrobrachion (Herklots, 1851), of Cote d'Ivoire (West Africa)

The present study describes the length-weight relationship (LWR), length-length relationship (LLR) and condition factor of the wild population of the shrimp Macrobrachium macrobrachion from the rivers of Cote d'Ivoire (West Africa). Samples were randomly collected from small-scale shrimp fisheries using bamboo traps. Of the thirteen analyzed morphometrics characters, only the second pleura width significantly varies between males (13.11 mm) and females (14.78 mm). All relationships between the considered variables were significantly linear, r2 ranging from 0.66 to 0.97. For length-length relationships, the allometry coefficient varied depending on groups, environments and characters, and ranged between 0.64 and 1.26. The three allometry types (negative allometry, isometry and positive allometry) were observed in this relation. In length-weight relationship, the coefficient ranged from 2.02 to 2.78, indicating a negative allometry. The condition factor values showed that females (0.70 plus or minus 0.06) were in better condition than males (0.657 plus or minus 0.07). Overall, the condition factor followed an east-west gradient, decreasing from eastern (0.70) to western (0.63) regions. These results constituted an important biological database on M. macrobrachion from the rivers of Cote d'Ivoire for further studies as ecology, reproductive biology, and aquaculture potentialities of this species.