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The growth performance of African catfish Clarias gariepinus (Burchell 1822) juveniles fed differently processed toad meal based diets was investigated in this study. Toads were collected, gutted, washed and processed into meals using four different methods, namely: oven drying at 60 oC (treatment 1); oven drying at 100 oC (treatment 2); removal of the skin and parotid gland before oven drying at 60 °C (treatment 3); and fermentation for 3 days before oven drying at 60 °C (treatment 4). Five isonitrogenous diets of 35% crude protein were formulated with inclusions of the processed toad meals (treatments 1, 2, 3 and 4) and a control diet with inclusion of fish meal (treatment 5). These were fed to juveniles of C. gariepinus (mean weight 13.08 ± 0.01 g) for 56 days. The results reveal that treatment 3 gave the best growth parameters, even more than the control diet with inclusion of fishmeal. This is further supported by the result of carcass analysis which revealed a similar trend. The cost analysis also confirms the superiority of treatment 3 over the other treatments due to its ability to produce 1 kg of fish with far less money than the other diets. The least growth indices, carcass protein and cost effectiveness were observed with dietary inclusions of fermented toad meal (treatment 4). It was therefore concluded that dietary inclusions of skinned and deglanded toad meal improves performance and production characteristics of the African catfish. [ABSTRACT FROM AUTHOR]

The performance of Clarias gariepinus (Burchell, 1822) fingerlings reared in white, green, blue, black and red coloured tanks was investigated. Each colour was tested in triplicate 1 m³ tanks with an initial stocking density of 100 fingerlings per tank (1.07 g). Fish were fed a commercial diet at 5% body weight per day for eight weeks. Fish weights were sampled every 2 weeks to adjust feeding rates. Tank colour had a significant effect (P < 0.05) on the overall performance of the fingerlings. Rearing in black tanks resulted in a higher daily feed intake (0.44 g) and better growth performance when compared to other tank colours, while the poorest performance was observed in blue and green tanks. Carcass protein and fat content at 8 weeks revealed a trend similar to that observed for growth. Also, serum glucose tests showed higher levels in light background tanks and were thought to be an indication of stress. Survival was not affected by tank colour. It was concluded that dark-coloured tanks such as black or red were better in comparison to light-coloured tanks for the rearing of African catfish fingerlings. [ABSTRACT FROM AUTHOR]

This study was conducted to determine the effect of storage conditions on the quality of feed and the aftermath effect of feeding fish with such feeds. Three commercial diets used for this study included Coppens®, Multifeed® and Vital feed®. Feed was stored either by opening the bag to the atmosphere (WO), the bag opened with neck tied using a rubber ring to prevent exposure to the atmosphere (OT) or sealed (SC) until the start of the feeding trials. The feed was stored under these conditions for six months. Nutrient analyses revealed significant changes in feeds held under the WO condition when compared with other storage conditions. Nutritive changes also varied with commercial feed type. Mould infestation of the feed was noticeable more in the WO condition of storage compared to the SC condition. After feeding C. gariepinus for fifty-six days, lesions were observed on fish fed mouldy feed held under the WO condition, which led to mass mortalities. Growth performance was higher in all fish fed SC stored feed, and for those fed Coppens® and Multifeed® under OT storage conditions. It is advised that storage of fish feeds up to six months should be undertaken with considerable care and attention. [ABSTRACT FROM AUTHOR]