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The effect of anaesthetic metomidate on the enzymes activities (Alanine transminase-ALT; Aspartate transaminase-AST; Alkaline phosphatase-ALP and Lactate dehydrogenase-LDH) in female Clarias gariepinus was investigated using different concentrations (0.00mlL-1control; 0.25; 0.75; 1.00; 2.00; 6.00; 8.00; 10.00 and 12.00mlL-1) in triplicates. The results from the study indicated that the anaesthetic caused a concentration dependent significant increase (p < 0.05) in the four enzymes under consideration. The h ighest activities in all the enzymes were observed in 12.00mlL-1 and the lowest in the control. The results from this work therefore suggests that the anaesthetics impair enzymes activities in the fish which was more noticeable in the fish exposed to higher concentration of 8.00-12.00m/L-1. Hence caution should be exercised in the application of this anaesthetics in sedation of C. gariepinus.

Abstract:The effectiveness of clove seed extracts as a viable anaesthetic agent in transportation of Tilapia guineensis were evaluated. Juveniles of T. guineensis (mean length 13.12cm ±1.20; mean weight 45.64g ±1.84) were exposed in three replicates to different concentrations (0.00mg/L-control; 5.00; 10.00; 15.00; 20.00 and 25.00mg/L) of clove seed aqueous extracts, extracted in water . The exposed fish were later transported in open plastic tanks from Buguma to Aluu, in Port Harcourt over a distance of 50km. Before and after transportation, glucose and cortisol levels in the plasma of the fish were assessed. The result of the study indicated a significant reduction (P<0.05) in the levels of cortisol and glucose in the plasma of the fish with increasing concentrations of the anaesthetics. The lowest survival rate (30.0%) was recorded in the fish transported with no anesthetics, while 100% survivals were recorded in fish exposed to 15.0 and 20.0 mg/L of the extracts. In conclusion, this study suggests that application of clove seed extracts within the range of 10.00 and 20.00 mg/L reduced the stress response in T. guineensis during transportation, thereby enhances their survival.

The issue of climate change has generated a lot of concern among the general public in Niger Delta region in recent time. It has been described in different ways by many people based on their views, perception and understanding. However, little considerations have been given to the impact of climate change on brackish water aquaculture in the coastal areas of Niger Delta. This study therefore, review critically, based on existing literature and field experience, the causes of climate change, impact of climate change on aquaculture production such as: increase in temperature, flooding of ponds, increase in water turbidity, heavy siltation of pond bottom, introduction of new species, collapse of farms infrastructure and fluctuations in salinity levels. Also, various adaptation and mitigation strategies that will ameliorate the impact of climate change in aquaculture operations, namely: reduction in human activities that are inimical to stable climate, selection of good site suitable for fish farming, provision of shading materials for fish cultured in tanks, raising of pond dykes, good management practices and improvement of monitoring and early warning systems are explicitly elucidated. As these strategies will go a long way in minimizing the impact of this menace, in the brackish water zone of the region. Moreover, efforts should be made by relevant institutions and agencies to come up with coordinated plans and policies that will reduce the effects of climate change on brackish water aquaculture in the coastal areas of Niger Delta.

Background and Aim: Niger delta environment has been exposed to organic and inorganic contaminants from industries and domestic wastes, thereby enhancing the capacity of the ecosystem into harboring a sizeable population of microorganisms. Most of these microorganisms are found in the water column, bottom sediment and water film, resulting in their elevated levels in seafood. Proper understanding of the transfer of microorganisms through the food web is essential to predict the exposure of seafood consumers to possible health consequences associated with its consumption in the coastal areas. Hence, the present study examines the microbial content of some sea foods such as: periwinkle (Tympanotonus fuscatus); mudskipper (Periophthalmus papilio); mullets (Liza falcipinis) Oyster (Crassotrea gasar) and water from Ekerekana and Buguma creeks, in the Niger delta, Nigeria. Methods: Seasonal variations in microbial content in some seafood namely: Periwinkle (T. fuscatus); mudskipper (P. papilio); mullet (L. falcipinnis) and Oyster (C. gasar) from Ekerekana and Buguma creeks, Niger delta, Nigeria were assessed. The sea foods were sampled monthly from both creeks for a period of eight months. Standard methods were employed in the evaluation of microbial load in each species. Results: The result indicated that the microorganisms isolated: total heterotrophic bacteria count, total vibro count; and total coliform count were more predominant in the wet season when compared to dry season months. Total coliform count bacteria exhibited some measure of elevation in the dry season months, an indication that they can be prevalent in both seasons depending on the type of human activities that is prevalent in the area. Conclusion: This study has shown that industrial and domestic wastes discharged into Ekerekana and Buguma creek resulted in high concentrations of pollutants in the water body, which promotes the growth of microorganisms in the water column and sea foods, this may pose a health hazard to humans as a final consumer of these organisms There is therefore the need to formulate appropriate policies and regulations for safeguarding the ecosystem from adding undesirable microbial population. isolated from waters which contain fecal materials [8-10]. Pathogenic bacteria in marine waters are most abundant in the sediments, they can also be found on the surface film, as well as in the water column [11]. As a result, fin and shell fishes found in marine environment often show elevated levels of these bacteria, which can cause disease in fish as well as human host that consume them. In most Niger delta communities, periwinkle, oyster, mullets and mudskipper are delicacies, they are in high demand among the populace living in these areas [12,13]. However, proper understanding of the transfer of microorganisms through the food web is essential to predict the exposure of consumers of this seafood to possible health consequences associated with their consumption. A large proportion of people living in rural and urban communities of N...