Economic interactions between feeding rates and stocking densities in intensive catfish Ictalurus punctatus production.

Feed represents the largest cost input in intensive catfish Ictalurus punctatus production. Daily feed rations are generally related to stocking densities, up to a point at which high feeding rates begin to affect water quality. There has been no prior research to analyze the economic interactions between feeding and stocking rates. Econometric techniques were used to estimate a Just-Pope catfish production function, which was used to compute marginal products of inputs, and to identify stocking and feeding rates associated with the boundaries between Stages I, II, and III of the production function. Survey data collected by USDA National Animal Health Monitoring System were used for this analysis. Maximum yield, when accounting for both stocking and feeding rates, occurred at about 30,000 fingerlings/ha. However, profit-maximizing stocking densities ranged between 16,942 and 21,312 fingerlings/ha, depending upon expected catfish and feed prices. Farmers stocking at higher rates could be attempting to maximize yield instead of profit.