Vol 6, No 3 , 2005

The diversity and abundance of fish species was studied in a sampling site on the Lake Kainji over a period of three months. A total number of four hundred and thirteen (413) fish from forty (40) species and fifteen (15) families were recorded during the study. The family bagridae dominated the catches with 18.37% in terms of abundance by number followed by Mochokidae with 13.5%% while Channidae had the lowest with 0.24%. The highest number of different species (8) was from bagridae followed by Mormyridae (6), then Characidae (5) and Mochokidae (4).

A Study was conducted on fleas of common domestic mammals in Benin City from April 2001 to April 2002, using handpicking and combing methods. Two species were recorded, Ctenocephalides canis (dog flea) and Ctenocephalides felis (cat flea) amounting to 2,662 specimens; 50.5% (1345) from dogs, 24.9% (662) from cats and 24.6 (655) from goats. 75.4% (2006) of the total flea collected from goats, cats and dogs were Ctenocephalides canis while 24.6% (656) Ctenocephalides felis occurred on cats only.

Distribution, sex ratio, abundance of various ovarian stages of development insemination rate, age composition and diurnal activity were studied in sweepnet catches of Musca domestica L. Collections were made from different location: house, refuse dump, market, cafeteria and poultry between 07.00h and 14.00h from October to December, 2003. Diurnal activity was also investigated by making sweeps at 07.00h, 12.00h and 17.00h from cafeteria. Market and cafeteria harboured the bulk of the population of M. domestica.

The distrubution of Bulinus globosus and Bulinus forskali in relation to the water velocities in the research site was investigated. Station 6 had the highest mean velocity of 22.82 cm sec. The analysis of variance for all the stations showed a very highly significant (P<0.01) defined as negative. Station 4 with a zero velocity (stagnant) had the highest number of both snails indicating an inverse relationship between velocity of water flow and abundance. The regression analysis indicated that increase in water velocity had a non-significant negative effect on the distribution of B.

The limnological characteristics of the aquatic habitat were studied with special emphasis on water temperature, calcium hardness and chlorine levels as they affect the abundance of Bulinus globosus and Bulinus forskali on one hand and their interfactorial effects on the other. The single regression analysis showed that calcium hardness was the only factor that showed direct significant (P<0.05) positive effect on abundance of B. globosus and B. forskali. Similarly, water temperature was significantly (P<0.05) negatively correlated with chlorine and calcium hardness levels.

Three cichlids, Chromidotilopia guentheri, Tilapia mariae and T. zilli were collected from the Osse River at Ikoro and examined for length frequency distribution and length weight relationships (LWR). The mean length and weight were 11.05±0.35cm and 51.75±5.63g for Chromidotilapia guentheri, 13.57±0.54cm and 124.67±17.54g for T. mariae and 17.45±0.69cm and 232.92±28.01g for T. zilli. The length frequency distributions for C. guentheri presented a slightly positively skewed distribution with modal length being 10.0 - 10.9cm size class. T.

An investigation was undertaken to assess the effect of Neem-fortified Cocoa pod husks soil amendment against the root-knot disease caused by Meloidogyne ingonita on cacao seedlings, Theobroma cacao L. cv. F3 Amazon. Cocoa pod husks (CPH), combined use of Neem leaves and CPH, and Neem seeds plus CPH decreased the number of juveniles and galling due to Meloidogyne incognita. The greatest decrease was obtained with Neem seed-fortified cocoa pod husks with a corresponding increase in the plant growth.