Preliminary study of the aquatic macrophytes of selected fish ponds and reservoirs in Makurdi, Benue State, Nigeria

A five months survey was conducted to identify the aquatic macrophytes in fishponds and reservoirs in Makurdi (Benue State, Nigeria) between August and December 1999. A total of 3-prominent aquatic macrophytes were identified: Ipomoea aquatica, Nymphae lotus and Echinochloa pyramidalis at two-study sites (site 1, receives organic manure effluent from a cattle ranch, site 2, receives inorganic fertilizer through application). Ipomoea aquatica were found restricted to site l, while Nymphae lotus and Echinochloa pyramidalis were found associated with site 2. Analysis of the results indicates high level of ammonia-nitrogen at site 1 compared to site 2. Mineral analysis of the plant tissues indicate high level of iron in Ipomoea aquatica and Nymphae lotus. Mineral concentration were found to be significantly higher (P,L, 0.05) in Ipomoea aquatica and Nymphae lotus when compared with concentration in Echinochloa pyramidali

Stock assessment of shrimps and prawn species of the Lower Benue and Niger River, Nigeria

The shrimps were collected from three sampling sites: on the River Benue at Makurdi, Benue state, on the River Niger at Jebba and Lokoja and Idah at Kogi state from January to April, 2011. Macrobrachium felicinum and Atya gabonensis were sampled during this period, with Atya gabonensis occurring more abundantly. Condition factors of freshwater shrimps Atya gabonensis from the two water bodies in Nigeria range from 1.875for species in Jebba in March to 3.330 for Lokoja in March. The parameter ”b” of the length - weight relationship of the fresh water shrimps are less than three (rangingfrom 1.0233 for species from Lokoja in April to 2.7717 for species from Makurdi in Feburary). These values suggest negative allometric growth. The length frequency of freshwater shrimps sampled shows that peak populations of length groups occurred in April for species from Jebba and Makurdi while peaks occurred in January for species from Lokoja.Peak frequencies were observed in length of 4.0 - 5. 4cm and 8.5 - 9.9cm in January as well as 5.5 -6.9cm for species from Lokoja and in the group of 5.5 - 6.9cm in April for species from Makurdi and 7.0-8.4cm in April for both Makurdi and Jebba

A survey of ectoparasites associated with 3 species of fish Auchenoglanis occidentalis, Oreochromis niloticus and Bagrus bayad in River Benue, Makurdi, Benue State, Nigeria

A survey of ectoparasites of three species of fish (Oreochromis niloticus, Auchenoglanis occidentalis and Bagrus bayad) of River Benue was carried out for a period of three weeks. Samples were collected directly from fishermen, at the river side (River Benue) in a plastic bucket and were carried to the laboratory. A smear samples from the skin were taken. Fins were cuted and gills were dissected and examine individually in saline solution in a Petri dish and platyhelminthes parasites as the most common ectoparasites of threes three species (Oreochromis, Auchenoglanis, and Bagrus). A total number of five hundred and seventy two (572) parasites were observed. Result of this study reveals that the large number of parasites were found on the gills (65%) of the three fish species studied, compared to skin (16%) and fins (19%) of the total parasites observed; among the three fish species studied. O. niloticus carries 33% while A. occidentalis carries 41% and B. bayad carries 26% of the total parasites seen. There was negligible difference in the level of infestation in the sexes (i.e. male and female) of Oreochronis and Bagrus. However, a great significance difference in the level of infestation was found in the sexes of Auchenoglani

Toxicity of herbicide Propanil on Oreochromis niloticus fingerlings

A static bioassay method to determine the acute toxicity of the herbicide propanil to Oreochromis niloticus was investigated under Laboratory conditions for 96 hours exposure period. Concentrations of propanil used include: 0.0096ml/l, 0.0103ml/l, 0.011ml/l and 0.012ml/l respectively. The lethal concentration (LC50) value of propanil on fingerlings of Oreochromis niloticus was 0.0097ml/l for 96 hours of exposure. The regression equation for probit kill from propanil was found to be Y = 29.84 + 12.33* log conc. (r2 0.9951, Y = Probit kill). Fish showed various abnormal behaviours upon exposure to propanil. Immediate reaction was erratic swimming and tendency to jump out of the test bowl. Others include: restlessness, un-coordinated movement, vertical swimming, air gulping, equilibrium loss, a period of quiescence and eventually death

Diseases associated with livestock integrated fish farming in Nigeria: a review

Just like other animals and humans, fishes are prone to diseases and predation. Diseases can be caused by one and/or combination of any of the following agents e.g. bacteria, fungi, viruses and parasites. Diseases have become a primary constraint to aquacultural development, which may affect the achievement of a desired impact for rapid development of fish culture in Nigeria. Apart from causing mortalities, they also cause loss of production quality, reduced growth, reduced fecundity, loss due to control measures and loss due to social factors associated with the farmer. This review has discussed the diseases that are associated with integrated fish farming including livestock cum fish farming, poultry-cum fish farming, Waste water fish farming, rice-cum fish farming e.t.c. The control of diseases associated with integrated fish farming requires a multi-disciplinary approach including chemotherapy, sanitation, routine hygiene, quarantine, genetic selection and immunoprophylaxis. The treatment and prevention of fish diseases follow the same principles used in chemotherapy of higher animals