Morpho-Fecundity of Berried African River Prawn (Macrobrachium vollenhovenii) in Asejire Reservoir, Nigeria

Abstract

The relationship between the morphology and fecundity of African River prawn (Macrobrachium vollenhovenii) in Asejire Reservoir, Nigeria was evaluated between March and August, 2014. A total of 209 M. vollenhovenii were collected during daytime from fishermen’s catch landed at Asejire Reservoir, Nigeria. Morphometric parameters and weight of each ovary were determined using graduated measuring board and OHAUS sensitive digital balance (Model CP4 13) to the nearest 0.1cm and 0.01 g respectively. Fecundity was estimated by direct counting of spawnable eggs from the ovigerous females under binocular microscope (Model XSZ-107BN). A simple linear regression analysis was used to depict the relationship between morphometric and fecundity parameters. Results indicated that the total weight of specimen collected ranged between 64.56g and 87.02g while the length ranged between 10.40cm and 15.70 cm with average of 13.98 ± 0.23cm. The number of eggs in the ovaries of the samples ranged between 66604.00 and 99178.00. Relative fecundity (weight) ranged between 4789.00 and 5151.00 while gonadosomatic index in the berried prawns ranged between 4.33 and 7.26 % with an average of 6.43 ± 0.25 %. All morphometric indices had positive relationships with fecundity parameters with the highest (98%) recorded in total length and numbers of eggs in the ovary. Total length was the best factor for predicting the fecundity of African River prawn in the study area. Hence, this result provides information for biologists and policy makers in the areas of reproduction and sustainability of M. vollenhovenii in Nigeria and other developing nations to further analyze its sustainability of biodiversity.