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Following disparity of earlier results, this study tested the performance of African catfish Clarias gariepinus fed dried brewer’s yeast slurry meal (DBYM) based diets. Fingerlings of C. gariepinus with pooled mean initial weight of 1.58±0.01 g were stocked in hapas (1 m × 1 m × 1 m) immersed in an earthen pond at a density of 15 fish per cage. Five diets with increasing substitution of soybean meal with 25%, 50%, 75%, and 100% of dried brewer’s yeast and a control without dried brewer’s yeast (0% substitution) were evaluated for 8 weeks. Palatability of diets reduced with increasing levels of DBYM. Growth and utilization parameters such as weight gain, feed conversion ratio, protein efficiency ratio, and specific growth rate differed significantly (p<0.05) among treated groups. Specific growth rate decreased with increasing substitution while the best feed conversion ratio was obtained in the diet devoid of DBYM. Protein efficiency and utilization decreased with increasing levels of DBYM. Body composition was also affected by inclusion of DBYM with significant differences (p<0.05) being observed across the diets. The trend in body composition follows the utilization of the diets. We conclude that the optimal range of inclusion and substitution of soybean meal with DBYM in C. gariepinus feed is between 1% and 14% of dry matter. [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]

The aquaponics production system integrates hydroponics and recirculatory aquaculture system for the simultaneous production of plants and fish. At a time, such as the postpandemic era, the aquaponics system represents an efficient green farming and eco‐friendly alternative to sustainable agricultural production. In this review, the history and development of the production systems were traced vis‐a‐vis its pros and cons. Although there has been much dispute about the origin of the system, the numerous records of developmental attempts in history have all led to the current complexity of the systems and their efficiency. Water conservation, improved performance, food security, less pollution, and low energy consumption are some of the advantages identified in the use of aquaponics systems for food production. Challenges to the domestication of the system, however, include moderately high start‐up capital, the need for stable electricity to operate the system, nutrient availability, as well as treatment of diseases in the system. Although the aquaponics production system could be a panacea for food security in Africa, modalities for the domestication of this technology are largely not in place, hence the need for some government interventions in this regard. [ABSTRACT FROM AUTHOR]

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]

Aquaponics is known to be a smart way of producing fish and crops simultaneously; however, there is a paucity of information about the extents of this system's efficiency over other conventional methods of food production. Thus, this study was designed to evaluate the performance of a catfish–pumpkin aquaponics system in comparison with recirculatory and static aquaculture systems (for fish performance), as well as irrigated and nonirrigated systems (for pumpkin performance). Results obtained showed that the production of fish in the aquaponics system was 29% and 75% more efficient than recirculatory and static aquaculture systems, respectively. The survival of the fish was also significantly improved probably due to better water quality in the aquaponics system. With respect to pumpkin production, yield in the aquaponics system was about five times the performance in irrigated land and eleven times those in nonirrigated land. This study gives definitive evidence to support the efficiency of the aquaponics system over other conventional food production methods. [ABSTRACT FROM AUTHOR]