Production Of Channel Catfish Ictalurus Punctatus Research Articles

Evaluation of the Economics of Multi-Batch Channel Catfish Ictalurus punctatus Production Fed an Industry Standard and Three Alternative Diets

High ingredient prices in 2008 led feed mills to manufacture new, less expensive feed formulations untested under commercial catfish farming conditions. Sixteen 0.1-ha ponds were stocked in multi-batch production with: (1) 32% protein control, an industry standard; (2) 32% protein alternative; (3) 32% protein corn gluten; and (4) 24% protein diets. A partial budget analysis evaluated the relative economics. The 32% control diet resulted in significantly greater yield of carryover fish. Feed conversion ratios of the control and 32% alternative diets were significantly lower than those of the 32% corn gluten and 24% protein diets, but visceral fat content was higher for the control and 32% alternative diets. The control diet was economically preferable to the alternative diets because the additional revenue from the greater yield of fish fed the control (industry standard) diet more than offset the reduced cost of the alternate diets evaluated.

Pond age–water column trophic relationships in channel catfish Ictalurus punctatus production ponds

Long-term temporal succession changes in nutrients, phytoplankton and zooplankton have not been previously investigated in aquaculture ponds. This study analyzed relationships of pond age with nutrients, zooplankton and phytoplankton populations, and incidence of off-flavor occurrence. Nutrient levels (iron, silica, total phosphorus, and total nitrogen), phytoplankton community composition, off-flavor compounds, and zooplankton community composition were determined for 10–11 replicate commercial channel catfish Ictalurus punctatus production ponds of ages 1, 2, 3, 4, 9, 10 or 15 years postconstruction. Data were analyzed using canonical discriminant function analysis, multivariate analysis of variance (MANOVA), and multiple regression approaches. Nutrients (N and P) accumulated in ponds during the first 3 years postconstruction; however, concentrations of these nutrients leveled off after this time. The continual addition of nutrients (as feed) makes standard chlorophyll–P relationships reported from natural lakes unable to account for variation in aquaculture data. Algal composition became dominated by filamentous cyanobacteria after year 4; zooplankton composition also was dominated by larger copepods and cladocerans in older ponds. Younger ponds had lower incidence and intensity of off-flavor relative to older pond water. If ponds are drained/reworked every 3–4 years, incidence of off-flavor should decline.