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

Feed represents the largest cost input in intensive catfish Ictalurus punct atus production. Daily feed rations are generally related to stocking densi ties, up to a point at which high feeding rates begin to affect water quali ty. There has been no prior research to analyze the economic interactions b etween feeding and stocking rates. Econometric techniques were used to esti mate a Just-Pope catfish production function, which was used to compute mar ginal products of inputs, and to identify stocking and feeding rates associ ated with the boundaries between Stages I, II, and III of the production fu nction. Survey data collected by USDA National Animal Health Monitoring Sys tem were used for this analysis. Maximum yield, when accounting for both st ocking and feeding rates, occurred at about 30,000 fingerlings/ha. However, profit-maximizing stocking densities ranged between 16,942 and 21,312 fing erlings/ha, depending upon expected catfish and feed prices. Farmers stocki ng at higher rates could be attempting to maximize yield instead of profit.