Recycle food wastes into high quality fish feeds for safe and quality fish production

Abstract

The amount of food waste generated from modern societies is increasing, which has imposed a tremendous pressure on its treatment and disposal. Food waste should be treated as a valuable resource rather than waste, and turning it into fish feeds would be a viable alternative. This paper attempts to review the feasibility of using food waste to formulate feed pellets to culture a few freshwater fish species, such as grass carp, grey mullet, and tilapia, under polyculture mode (growing different species in the same pond). These species occupy different ecological niches, with different feeding modes (i.e., herbivorous, filter feeding, etc.), and therefore all the nutrients derived from the food waste could be efficiently recycled within the ecosystem. The problems facing environmental pollution and fish contamination; the past and present situation of inland fish culture (focusing on South China); upgrade of food waste based feed pellets by adding enzymes, vitamin-mineral premix, probiotics (yeast), prebiotics, and Chinese medicinal herbs into feeds; and potential health risks of fish cultivated by food waste based pellets are discussed, citing some local examples. It can be concluded that appropriate portions of different types of food waste could satisfy basic nutritional requirements of lower trophic level fish species such as grass carp and tilapia. Upgrading the fish pellets by adding different supplements mentioned above could further elevated the quality of feeds, leading to higher growth rates, and enhanced immunity of fish. Health risk assessments based on the major environmental contaminants (mercury, PAHs and DDTs) in fish flesh showed that fish fed food waste based pellets are safer for consumption, when compared with those fed commercial feed pellets.

Occurrence and Levels of Aflatoxins in Fish Feeds and Their Potential Effects on Fish in Nyeri, Kenya

“…Aquaculture development in Kenya is faced with several challenges such as unavailability of good quality and affordable fish feeds [6]. Fish feeds are the highest contributors to fish production costs and therefore greatly impact the economic returns from fish farming [7]. Additionally, fish nutrition and feed quality directly affect fish health and productivity.…”

Effect of fasting and feeding on growth, intestinal morphology and enteroendocrine cell density in Rhamdia quelen juveniles

“…Several studies on fish nutrition were carried out in the last years, with particular attention to the mechanisms that regulate appetite (Narnaware & Peter, 2002;Rønnestad et al, 2017;Silverstein & Plysetskaya, 2000;Volkoff, 2016;Volkoff, Hoskins & Tuziak, 2010;Volkoff et al, 2005). The knowledge of actions and interactions of hormones and neurotransmitters that influence the energy balance and the control of body weight would optimize growth (Volkoff et al, 2010) and reduce production costs related to food (>50%) (Wong, Mo, Choi, Cheng & Man, 2016).…”

Food Waste and Byproducts: An Opportunity to Minimize Malnutrition and Hunger in Developing Countries

“…Along with the production of such high amount of fishery products huge quantities of fishery residues were also generated. Residues commonly consists of viscera, carcass, head, skin or bones and can represent from 50 to 70% depending on species and processing strategies and from this, only about 30% is destined to their re-utilization (Wong et al, 2016). For this reason, efforts are currently being made to the re-valorization of this class of byproducts to be used as a substitute for protein in animal feed and for the production of functional products.…”