Projected annual production capacity affects sustainability of rainbow trout (Oncorhynchus mykiss Walbaum, 1792) reared in concrete ponds in terms of energy use efficiency

Abstract

Energy use efficiency is an important criterion for determining sustainability in aquaculture and for this purpose, cultural energy use and energy use efficiency of a rainbow trout (Oncorhynchus mykiss) commercial farm rearing in concrete ponds with 350 t projected annual production capacity was investigated to determine the sustainability of trout farm. Total cultural energy expended consisted of cultural energy expended on compound diet, general management, transportation, and machinery, equipment, and construction. Cultural energy expended on feed constituted 77.88% of total cultural energy expended. In order to standardize the inputs, cultural energy inputs were provided for kg of fish and 1000 fish. As projected annual production capacity increased, cultural energy expended for kg of marketed carcass and fillet decreased. Average of three years for protein energy production efficiency in carcass and fillet which is Mcal of cultural energy expended to receive Mcal of energy coming from protein in carcass and fillet were 5.92 and 8.33, respectively and it decreased as projected annual production capacity increased. The average of three years for cultural energy use efficiency for carcass and fillet which is calculated by dividing total cultural energy expended by energy deposited in carcass or fillet were 4.82 and 6.79, respectively, and projected annual production capacity affected it as it decreased with increasing production capacity. Results showed that cultural energy use efficiency is a good indicator of sustainability and in order to determine the sustainability of production systems or aquatic species, this indicator should be considered to compare the overall sustainability and this may also shed some light on for future policymaking.