Comparative Studies of African River Prawn, Macrobrachium vollenhovenii (Herklots, 1857) in Ose and Osun Rivers, Southwestern Nigeria

Abstract

Interest in African river prawn, Macrobrachium vollenhovenii has increased recently mainly because of the possibility of its commercial culture. This study investigated the abundance, sex ratio and condition factor of African river prawn M. vollenhovenii and selected water qualities in Ose and Osun Rivers, Southwestern Nigeria. The water quality parameters of the rivers were recorded in-situ using Hana HI 9828 water multi-parameters. The temperature, pH and dissolved oxygen contents in Ose and Osun Rivers were not significantly (P>0.05) different from each other but the salinity values in both rivers were statistically (p˂0.05) different. The species abundance was 31.40% (females); 68.60% (males) in Ose River and 38.52% (females); 61.48% (males) in Osun Rivers. The Sex ratio of 2.18 : 1 and 1.60 : 1, and condition factor of 1.49±0.09 and 1.40±0.07 were recorded in Ose and Osun Rivers, respectively. All the water quality parameters studied were within the recommended ranges for the culture of freshwater prawn. The male populations of M. vollenhovenii in Ose River grew better and were more abundant than the females in both seasons. The condition factor was better in wet season than dry season. The research has provided a baseline data on the biology of African river prawn, M. vollenhovenii in Ose and Osun Rivers, Southwestern, Nigeria.