Impact of species and their edible parts on the macronutrient and mineral composition of fish from the same aquatic environment, the Gilgel Gibe Reservoir, Ethiopia.

Abstract

Fish is an important source of easily digestible animal protein and other essential nutrients. It plays a pivotal role in food security and poverty alleviation in developing countries. However, the nations of the global South consume a limited number of fish species. This study aimed to evaluate the macronutrient and mineral composition of Whole fish (Labeobarbus intermedius, Garra quadrimaculata) and fillet (Oreochromis niloticus, Labeobarbus intermedius). A total of 64 fish samples were collected from Gilgel Gibe reservoir, Ethiopia, and analysed for its macronutrient and mineral composition. The proximate composition and mineral contents of fillets and whole body samples were determined. The whole fish showed a much higher fat and ash percentage than the fillets (p<0.05). The fillets contained a much higher protein concentration than the whole fish (p<0.05). The higher Ca:P ratios in whole fish compared to fillet in our study confirm the importance for a healthy human skeletal development, especially in diets where Ca is typically lacking. Whole Garra appeared to be containing important trace elements such as zinc and iron, a feature that was not found to the same extent in the whole Labeobarbus. These differences may find its origin in the feeding pattern of these fish species in the reservoir. The advantage of benthic species such as Garra to enrich the human diet with essential minerals may, however, coincide with the accumulation of toxic heavy metals as a potential result of soil erosion.