Impact Of Lamda Cyhalothrin Pyrethroid Insecticide On The Uptake Of Cations And Anions By The Gills Of Freshwater Catfish Hybrid Juvenile

The impact o acute exposure of karate (Lambda cyhalothrin pyrethroid) insecticide was evaluatedin a 4 – day exposure period at 20, 40, 60 and 80 ppm to Heterobranchus bidosals(+) X Clarias gariepinus(&#9794;) fngerlingsshowed the 96-hlc 50 as 25.11 ppm. The threshold value was 25. 11 ppm. The gills of the exposed fish analyzed showed a significant decrease in all major cations and anions(C1-, Ca2+, Na+, K+, Mg2+) at P < 0.05). There was no inhibion of upake of the catons and anions (C1-, Ca2+ Na+, K+, Mg2+). Their uptakeincreased rapidly during the 24 hr period and dropped at 48hr and 72 hr and gradualy increased at the end of 96 hr showing that it was time dependent. During the exposure period the fish stood in upright position with their snouts above the water surface gasping for air. Other behavioral characteristics of the exposed fish were peeling of the skin, initial increase in opercula movement, curvature of the body, loss of balance, erratic swimming and quietness Based the outcome of this research and under similar experimental condition it is the recommendation of this research that this pyrethroid will affect the uptake of the major cations and anions. It further advises environmental officers, crop farmers and insecticides habitual users to be cautious on the use of thisinsecticide because of the resultant consequences of the misuse. Keywords: Karate, Uptake, Cations, Anions, Gills, Catfish, Toxicity Animal Research International Vol. 4 (1) 2007 pp. 591-59

Food and Feeding Habits of Campylomormyrus tamandua in Anambra River, Nigeria

The food and feeding habits of 417 samples of Campylomormyrus tamandua (Osteichthyes Mormyridae) in Anambra River, Nigeria were studied from October 2002 to March 2004. Fish samples were collected monthly at Otuocha and Ogurugu river ports along the Anambra river using a fleet of gill nets of various mesh sizes, traps and hook and lines. Out of the eight (8) categories ofood consumed, the most dominant group was benthic invertebrates (IFS = 4492) followed by alochthonous invertebrates (IFS = 33.40) whe the least was mud/sand (IFS = 10.02). Variaton in the stomach fullness condition showed that 82 (19.66%) ofthe stomachs studied were empty 40 (9.59%) were full while 295 (7074%) were partially filled Food richness and diet breadth showed no significant difference between the seasons and sex respectively (P > 0.05). The trophicvariations and flexibility in C. tamandua are discussed. Keywords: Anambra river, Campylomormyrus tamandua, Food, Feeding habitsAnimal Research International Vol. 3 (1) 2006 pp. 410-41

Ecological risk estimation of heavy metal pollution in roadside dust of Ado-Odo Ota, Southwestern Nigeria

Increased industrial, commercial and transport activities have constantly introduced air pollutants such as heavy metals in the atmosphere. Roadside dust samples were collected from 10 locations along Ota-Benin road, analysed for Cr, Cd, Co, Ni, Pb, Fe, Mn, Cu, As and Zn, and the ecological risk was evaluated for the heavy metals’ concentration in the roadside dust particles using the Hakanson method. The results revealed that Cd (3.103 mg/kg) and Cu (mg/kg) surpassed the threshold effect level. Pollutant source identification analysis revealed possible origin from motor oil, plastics, metalliferous extraction, dyes, and paints industries. The contamination factor for Ni was found to be at a moderate level in location SM8, SM9 and SM10 and a similar category was observed for Pb in location SM7, SM8, SM9 and SM10. Zn concentration in location SM5, SM6, SM7, SM8, SM9 and SM10 fell within the moderate contamination factor zone as well. Furthermore, the mean i r E of the individual metals in the sample region followed the order of Cd > Ni > Pb > As > Cu > Zn > Cr indicating a high risk associated with cadmium within the sample region

Population structure and evolutionary history of the greater cane rat (Thryonomys swinderianus) from the Guinean Forests of West Africa

Grasscutter (Thryonomys swinderianus) is a large-body old world rodent found in sub-Saharan Africa. The body size and the unique taste of the meat of this major crop pest have made it a target of intense hunting and a potential consideration as a micro-livestock. However, there is insufficient knowledge on the genetic diversity of its populations across African Guinean forests. Herein, we investigated the genetic diversity, population structures and evolutionary history of seven Nigerian wild grasscutter populations together with individuals from Cameroon, Republic of Benin, and Ghana, using five mitochondrial fragments, including D-loop and cytochrome b (CYTB). D-loop haplotype diversity ranged from 0.571 (± 0.149) in Republic of Benin to 0.921 (± 0.013) in Ghana. Within Nigeria, the haplotype diversity ranged from 0.659 (± 0.059) in Cross River to 0.837 (± 0.075) in Ondo subpopulation. The fixation index (FST), haplotype frequency distribution and analysis of molecular variance revealed varying levels of population structures across populations. No significant signature of population contraction was detected in the grasscutter populations. Evolutionary analyses of CYTB suggests that South African population might have diverged from other populations about 6.1 (2.6–10.18, 95% CI) MYA. Taken together, this study reveals the population status and evolutionary history of grasscutter populations in the region

Length-Weight Relationship And Condition Factor Of Distichodus Species Of Anambra River

The length-weight relationships (LWRs) and condition factor of Distichodus 169 Distichodus rostratus, 167 D. brevipnnis and 163 D. engycephalus from Anambra river were investigated from November 2004 to October 2005. LWRs showed that the b-values for the combined sexes were 3.051, 3.114 and 3.040 for D. rostratus, D. brevipinnis and D. engycephalus respectively. Thus, all the Dstichodus species exhibited isometric growth with high, positive and significant correlations. The mean condition factor for the combined sexes was 1.12+-048, 1.06 +- 022 and 0.94+- 0.33 for D. Rostratus, D. brevipinnis and D. engycephalus respectively. Except for D brevipinnis, there was no significant difference (P > 005) in the condition facor (K) between the males and females of other species The condition factor also demonstrated interseasonal variability in all the species. The importance of condition factor in the breeding activities o Distichodus species is discussed. Keywords: Distichodus, Length-weight relationships, Condition factorAnimal Research International Vol. 3 (2) 2006 pp. 461-46

Comparative studies on the growth and survival of African catfish, Clarias gariepinus (Burchell, 1822) juveniles reared in cages suspended in concrete tank and earthen pond in Umudike, Abia State

No Abstract.Bio-Research Vol. 5 (1) 2007: pp. 210-21

Sex Discrimination Among Four Mormyrid Species Of Anambra River System Nigeria

Sex discriminating characters of four mormyrid species caught from Anambra river basin, Nigeria were investigated. Sexual dimorphism occurred in only one transformed character – dorsal fin base length and in four raw morphometric characters namely totallength, standard length, dorsal fin base length and anal fin base length. These characters are recommended as key characters in mormyrid taxonomy. Keywords: Mormyridae, sex dimorphism, Anambra river Animal Research International Vol. 1 (3) 2004 pp. 169-17

Harnessing Aquatic Physicochemical Parameters Influencing Macroinvertebrate Fauna In Anambra River Basin For Sustainable Fish Productivity

The management-oriented background for harnessing aquatic physicochemical parameters influencing macro invertebrate fauna of Anambra River basin for sustainable fish productivity was studied. The intra seasonal variability in the water quality of the river revealed mean transparency of 1.79 cm, Conductivity of 28.81 &#956;scm-1, nitrate-nitrogen of 3.23 mgl-1, total hardness of 6.43 mgcaco3L-1, biological Oxygen Demand (BOD) of 3.62 mgl-1, No3-N/Po4-P 0.54 ratio and Co2/DO o0.81 were significantly higher in the dry season than all other parameters which were signicantly higher in he wet season. A toal of 1808 individuals (mosty adults) belongng to 97 species of macro-invertebrate fauna were collected. The overall composition of the fauna in the river basin was dominated by coleopterans and the hemipterans. The estimated annual fish yield of the river basin was 72.91 kg/ha based on a morphoedaphic index. The water quality of the River can be harnessed by controlling and/or prohibiting the discharge of municipal effluents and domestic garbage into the river as well as the continuous use of the riparian zone for agronomy. The maintenance of periphera 50/60 m of thick riparian vegetation can act as buffer strp to check bank erosion is suggested. Keywords: Macro invertebrates, Physicochemical Parameters, Harnessing, Fish yield Animal Research International Vol. 4 (2) 2007 pp. 705-71

Macroinvertebrate Fauna Of A Nigerian Freshwater Ecosystem

A survey of macro invertebrate fauna of Anambra River was carried out for 22 months at Otuocha,Ogurugu and Nsugbe. The macro invertebrates were sampled using kick sampling technques and scoop nets. Sampled specimens were identfied to generic level. During the study a total of 21 genera of macroinvertebrates belongingto 13families were identified. The fauna was composed ofGyrinus sp. (29.2%), Macrobranchium sp. (19.6%), Ranatra sp. (13.2%) and Agabus sp. (3.5%). The margalef\'s index of fauna richness showed that Otuocha station had the highest species richness (12.70), followed by Nsugbe (7.01), and Ogurugu (6.80) stations. The least fauna diversity of 021 was registered at Nsugbe as against 3.15 at Otuocha and 0.86 at Ogurugu. The McNaughton community dominance index was more pronounced at Nsugbe (53.1) than at Otuocha (49.69) and Ogurugu (47.04). Jackson\'s fauna similarly index showed that the fauna at Otuocha and Ogurugu were more closely related (0.64) than the fauna at Nsugbe. Keywords: Macroinvertebrates, Anambra River, NigeriaAnimal Research International Vol. 4 (1) 2007 pp. 611-61