Embodied Resources in Fish and Shrimp Feeds

Global averages were obtained for amounts of energy, land, water, wildfish, nitrogen, and phosphorus embodied in aquaculture feed ingredients. These data allowed amounts of these embodied resources to be calculated for typical feed formulations for channel catfish, Ictalurus punctatus; hybrid catfish, I. punctatus. xI. furcatus.; Vietnamese catfish, Pangasius spp.; Atlantic salmon, Salmo salar; rainbow trout, Oncorhynchus mykiss; tilapia, Oreochromis spp.; whiteleg shrimp, Litopenaeus vannamei; and black tiger shrimp, Penaeus monodon. Embodied resource use per m. t. of feed varied among species: energy, 4.90-12.48 GJ/m. t.; land, 0.082-0.312 ha/m. t.; water, 502-1227m(3)/m.t.; wildfish, 0-2880 kg/m. t.; nitrogen, 3.08-8.63 kg/m. t.; phosphorus, 1.16-5.62 kg/m. t. These calculations did not account for variations in site-specific factors related to embodied resources and feed composition and use. But they suggest that reducing feed conversion ratio (FCR) by 0.1 unit for the seven species (species groups) could potentially reduce feed use by around 1.1 million tonne (Mt) while conserving 9.8 million GJ of energy, 270,000 ha of agricultural land, 1.4 billion m(3) of freshwater, and 1.24 Mt of wildfish. Reduction of the FCR is a powerful means of lessening farm-level production costs and negative impacts of feed production and use.