The nutritional implication of processed maggot meals, hydrolysed, defatted, full‐fat, sun‐dried and oven‐dried, in the diets of Clarias gariepinus fingerlings were evaluated. The nutrient density, proximate composition, gross energy and mineral constituents of the maggot meals were determined. Five isonitrogenous and isocaloric diets were formulated to provide 40% crude protein in which fish meal in the reference diet was completely replaced by any of the following processed maggot meals: oven‐dried full‐fat (ODM), sun‐dried full‐fat (SDM), defatted oven‐dried (DODM) and defatted sun‐dried (DSDM) maggot meals respectively. Fish were fed ad libitum in triplicate treatments for 56 days in glass tanks. Biological evaluations of the fish were based on growth performance and nutrient utilization indices. The result of the nutrient composition analysis showed that processing methods of defattening and drying influenced the nutrient density of maggot meal, with crude protein content ranging between 43.30% and 46.70% for full‐fat sun‐dried and hydrolysed/defatted oven‐dried maggot meals respectively. The result showed that growth performance and nutrient utilization of fish fed DODM and DSDM dietary inclusions were not significantly different and similar to fish fed the fish meal‐based diet. However, fish fed the diet containing SDM exhibited lower daily weight gain, protein efficiency ratio and specific growth. Generally, fish performed better when fed diets containing defatted maggot meals than full‐fat maggot meal, and compared favourably with fish fed the fish meal‐based diet.

A total of 16 wild underexploited leguminous crop seeds (belonging to the subdivisions Mimosoideae, Caesalpinoideae, and Papilionoideae) were investigated for their proximate composition and mineral content with the hope of establishing their potential as sources of feed for livestock and their possible industrial uses in Nigeria. Members of the leguminoseae studied were fairly good sources of protein.Mean protein content was 21.83 f 6.80%. Most members of the subdivision Mimosoideae contained high amounts of protein. These are typified by Acacia senegal (38.89%), Parkia clappertoniana (29.40%), Prosopis africana (25.74 %), and Tetraptera tetrapleura (25.47%). Pterocarpus osun (Papilinoideae) contained a crude protein level of 28.08%. Ether extract, crude fiber, and ash levels for these wild species were fairly high. Generally, these leguminous seeds appeared to be good sources of calcium, phosphorus, and potassium. They however contained low levels of sodium. Wide variability existed in both the zinc and manganese contents among the species investigated. INTRODUCTION The search for novel high-quality but cheap sources of protein and energy has continued to be a major concern of government and bodies charged with the responsibility for food and nutrition in many parts of the developing world. However, it has been suggested that, more than anything else, lack of information on the composition and utilization of the many and varied protein and energy sources indigenous to the tropics is the major problem rather than a real shortage.The formulation of feeds for either livestock or fish implies an accurate knowledge of the nutrient composition and feeding value of the available feedstuff resources. The availability of such information would lead to more judicious use of some more commonly known sources and perhaps step up the use of hitherto neglected sources.The aspiration of developing countries to be industrially self-sufficient has demanded huge financial spending in agriculture and the search for locally utilizable raw materials among the neglected agricultural crops. However, before such crops could be used, information is needed on their chemical characteristics. Data have accumulated in literature (Oyenuga, 1968) on the proximate composition and the mineral content of the more commonly used legumes and oilseeds. The work reported here was aimed a t providing basic information on the proximate and mineral composition of some underexploited and underutilized leguminous crop seeds in Nigeria. MATERIALS AND METHODSMature seeds of 16 members of the family leguminoseae belonging to three subdivisions (Mimosoideae, Caesalpinoideae, Papilionoideae) were used in this study. A list of species investigated is presented in Table I. The seeds were collected from the seed collection and processing unit of the Forestry Research Institute, Ibadan, Nigeria, which collected the seeds from various locations in the savannah (semi-arid) region of Nigeria during the fruiting season. The leguminous seeds were identified by the me...

The use of solar‐dried duckweed, Spirodela polyrrhiza L. Schleiden, as a dietary protein component for tilapia, Oreochromis niloticus L., reared in glass tanks was evaluated. Six isonitrogenous diets (30% crude protein) were fed to all‐male tilapia fingerlings for 56 days. The fish meal protein in the diets was substituted at a rate of 5%, 10%, 20%, 30% and 100% with duckweed. A diet without the duckweed served as a control. Growth performance and nutrient utilization of fish were based on daily weight gain, specific growth rate, feed conversion ratio, protein efficiency ratio and protein productive value. There were no significant differences (P > 0.05) in growth performance and nutrient utilization of fish fed on diets containing up to 20% duckweed inclusion and the control. However, increases in dietary duckweed inclusion resulted in progressively reduced growth performance and nutrient utilization of fish. Diet without fish meal (100% duckweed) gave the poorest result. The most cost‐effective diet in terms of cost per unit gain in weight of fish was obtained with 30% duckweed dietary inclusion. The result showed that solar‐dried up to 30% duckweed dietary inclusion as a replacement for fishmeal in practical diets supported fish growth and was cost‐effective.

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