Seasonality in some tropical harpacticoid copepods (Crustacea) from West African coastal river

Studies on the occurrence and seasonality of some harpacticoid copepods (crustacean) from a West African coastal river were carried out. An all year round sampling was made to cover the twelve months of the year, using plankton nets of 55µm and 100µm mesh sizes. Three species of harpacticoid copepods were identified, namely: Nannopus palustris, Diarthrodes cf major and Bryocampus minutes. While Nannopus palustris showed peaks in the dry season months of January and February, Diarthrodes cf major and Bryocamptus minutes showed peaks in the rainy season months of July and August.

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Nematicidal potential of some indigenous plant extracts against root-knot nematode on cacao

The effect extract of Ocimum gratisimum L., Carica papaya, Azadirachta indica A. Juss, Vernonia amygdalina and Bixa orellana L. on pathogenicity and reproduction of Meloidogyne incognita race 3, the causal organism of the root-knot disease of cacao was investigated in the greenhouse. Leaf extracts were prepared by blending and filtration of 25g of chopped leaves in 100ml of distilled water. Each cocoa seedling in a naturally infested soil received 40ml water extract of the leaves. Nematode populations were reduced by the application of the extracts in a descending order of A. indica, B.

Influence of Neem-fortified cocoa pod husks soil amendment on Meloidogyne incognita in cocoa.

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.

Allometric indices of Chromidotilapia guentheri (Sauvage 1882), Tilapia mariae (Boulenger 1899) and Tilapia zillii (Gervais 1848) of the Osse River, Southern Nigeria

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.

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Some limnological studies of an aquatic habitat used for fishing and irrigation in Ngala, Borno State, Nigeria

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.

Application of biostatistics to the effects of water velocity on the Adistribution of Bulinus globosus and Bulinus forskali in an irrigation scheme in Borno State, Nigeria

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.

Age structure and diurnal activity of Musca domestica L. (Diptera: Muscidae)

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.

Observation on fleas of common domestic mammals in Benin City, Nigeria

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.

Current diversity and abundance of fish species in a sampling site on Lake Kainji

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).

Economics of fish fingerlings production in outdoor culture system

The cost of acquiring a fingerling for stocking had always been haphazardly fixed to the detriment of the fish farmer because the cost of acquisition has no economic consideration of its cost of production. More often that not the fish farmer pays more far above the cost of production. This paper looks into the economics of producing one fingerling in two separate outdoor culture systems aerated and unaerated.

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