Cy. Cho et al., DEVELOPMENT OF HIGH-NUTRIENT-DENSE, LOW-POLLUTION DIETS AND PREDICTION OF AQUACULTURE WASTES USING BIOLOGICAL APPROACHES, Aquaculture, 124(1-4), 1994, pp. 293-305
As with agriculture, aquaculture is a biological conversion process of
food into animal production, but it differs, from a waste management
viewpoint, from animal farming. Firstly. prediction of feed intake and
optimum level of feeding are difficult, hence feed waste contributes
a relatively large proportion of total waste output in most operations
. Secondly, collection of wastes, both solid waste and soluble or diss
olved waste, is also very difficult and wastes are rapidly dispersed i
nto the surrounding water. These factors create many problems which ar
e generally unknown to other animal farming operations. However, susta
inable aquaculture can be maintained through nutritional strategies fo
r the management of aquaculture waste (NSMAW) by minimizing waste outp
uts from the source. The basic principles are formulation of high-nutr
ient-dense diets and development of efficient feeding systems based on
energetic data. Monitoring and quantitation of waste output is also c
arried out indirectly using digestibility measurements and comparative
carcass analyses. This is a biological and nutritional approach rathe
r than a conventional chemical approach to effluent analyses. These la
tter are laborious, inaccurate and expensive. Recent high-nutrient-den
se (''low-pollution'') diet formulations output less than 200 kg solid
waste and less than 5 kg P per tonne fish produced, but achieving thi
s reduction of waste output requires completely revised feeding standa
rds based on an average 1 5 MJ DE/kg salmonid fish produced.