ABSTRACT:The use of potentially toxic ripening agents is common in developing countries. Four ripening agents namely calcium carbide, potash, African mango and jathropha curcas leaf were used and compared with a control with no ripening agent. Result showed that RB1 and RB2 were the first to ripen at 3days with RB5 at 6 th day. Protein content reduced in the ripened samples in the order of 4.12>3.68>3.04>2.52>1.99>1.77%. Protein value was lowest when calcium carbide was used. Fat ash and fiber contents range between 0.28-1.72, 0.75-2.75and 0.50-1.75% respectively. The moisture content increased from 65.50 to 74.0%, while carbohydrate content range is 17.49-29.29%. Pb, Cu, Zn and Mn values of 0.22, 0.87, 1.96 and 0.67ppm was highest in calcium carbide ripened banana and lowest in the control 0.09, 0.26, 0.37 and 0.19 ppm. © JASEM http://dx.doi.org/10.4314/jasem.v18 i2.14 Ripening is a biochemical process which involves a series of physiological changes in colour, aroma, flavor and texture. Banana is a climateric fruit showing an increase in respiration resulting in colour, flavor, aroma and texture changes. It is usually eaten raw when ripe and is a major starchy food common in Sub-Sahara Africa and Asia, providing more than 25% of carbohydrate (Adeniji et al, 2007). The consumption of banana cuts across every age group, from little children to adults, and it supplies necessary calories and essential micronutrients. Once harvested it is highly perishable, with short shelf life leading to high post harvest losses of about 20-50% due to poor handling and quality deterioration (Ajayi and Mbah, 2007;Zewter et al, 2012). In order to reduce the high post harvest losses, bananas are harvested when green but mature, and artificially ripened when needed with the use of ripening agents. Ripening agents are substances which hasten the ripening process, and it comes in different forms. These include ethylene gas, ethephon, ethylene glycol, etherel and calcium carbide (Singal et al, 2012); African bush mango fruit (irvingia gabonesis) and leaves, Palm nut, Cassia leaves, Yellow Pawpaw leaves, torch light battery, calcium carbide, potash and ash (Ajayi and Mbah, 2007). African mango fruits, calcium carbide and newbouldia leaves were also reported by Adewole and Duruji (2010). According to Singal et al (2012), the commercial practice is to use these ripening agents to artificially ripen the fruits at the destination market before retailing. Ethylene gas is expensive to produce so low cost indigenous ripening technologies involving the use of hazardous materials are used (Singal et al 2012;Ajayi and Mbah, 2007). The adverse potential of calcium carbide as a ripening agent has been established (Singal et al, 2012) while other chemical ripening agents like ethepon, etherel and ethylene glycol are also considered hazardous to health and they have to be used within recommended safe limits (Hakim et al 2012;Food and Beverage Online, 2010). The use of toxic and suspicious ripening agents is of great concern as the activities of human ...

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This study detected, identified and determined the incidence of parasites present in and on Clarias gariepinus, Sarotherodon galilaeus, Oreochromis niloticus and Tilapia zillii in Ero reservoir, a tropical reservoir situated in Ikun-Ekiti, Nigeria. Fish species were randomly obtained from fishermen at the reservoir during the rainy season. Out of 55 fish samples examined, 17 (30.9%) fishes were invaded. 11(20.0%) were infected by Protozoans (Ciliates and Flagellates) and 6(10.9%) were infected by Metazoans (Myxosporean and Nematode). Parasitological examination of the 55 fish samples showed 41.2% incidence for C. gariepinus, 17.6% for S. galilaeus, 29.4% for O. niloticus, and 11.8% for T. zillii. A total of 59 parasites were recovered comprising 36 protozoans and 23 metazoans. Parasite infections were found on the skin, fins, gills, intestine, liver and kidney. Total number and percentage of parasites recovered were tabulated in relation to their host prevalence and location of specificity.

-Th e study determined the variation in the morphological and meristic features among four populations of Clarias gariepinus Burchell, 1822 obtained from Owena Dam and River Oluwa in Ondo State and Rivers Omo and Ogbere in Ogun State, both in Nigeria. A total of ninety fi ve (95) and one hundred and twenty (120) fi sh specimens collected from Ondo and Ogun states respectively were measured using standard procedures and the results were analysed using Analysis of variance and multivariate analyses. Th e results obtained from the ANOVA and Principal Component Analyses of Clarias gariepinus from the four populations revealed heterogeneity for most of their characters. Th erefore, the morphological diff erences between the wild African catfi sh found in Ondo and Ogun state populations could be linked to genetic diff erences or environmental factors or a combination of both factors. Hence, this study concluded that the populations are diff erent which could imply high genetic diversity if molecular marker techniques are employed in further studies.

Objectives: To study ichthyofauna composition of Alape River, Igbokoda, Ilaje Local Government Area of Ondo State, Nigeria. Method: Sampling was done for a period of three months, from the month of November 2019 to January 2020. Data for this study were based on the record of fish caught by local fishermen. Findings: A total of twenty thousand, four hundred and nine (20,409) individual fishes of six species (Heterotis niloticus, Clarias gariepinus, Chrysichthys nigrodigitatus, Gymnarchus niloticus, Oreochromis aureaus and Hepsetus odoe), belonging to six families (Arapaimidae, Clariidae, Claroteidae, Gymnarchidae, Cichlidae and Hepsetidae) were recorded for the whole period of study. The overall comparison among the months of study shows that January recorded the highest catch (6,919) with an overall relative percentage abundance of 33.9%, followed by December (6,871) with 33.67%. The least catch (6,619) was observed in the month of November with a relative percentage abundance of 32.43%. The study showed that Clarias gariepinus and Oreochromis aureus were dominant fish species, Chrysichthys nigrodigitatus was subdominant , Heterotis niloticus and Hepsetus odoe were occasional while Gymnarchus niloticus was rare in River Alape. The results of this study showed that the river has low fish species composition and abundance in spite of the size of the river. Considering this fact, there is need for further survey to cover more months. There is also a need to evolve strategies for effective utilization and proper management of the river for optimum fish production, sustainability and conservation.