Aquaculture America 2021

August 11 - 14, 2021

San Antonio, Texas

EFFECT OF UNDERSTOCKING DENSITY OF CHANNEL CATFISH FINGERLINGS IN INTENSIVELY AERATED MULTIPLE-BATCH PRODUCTION

Ganesh Kumar, David Wise, Menghe Li, Suja Aarattuthodiyil, Shraddha Hegde, Billy Rutland, Sean Pruitt, Matt Griffin, and Lester Khoo
 
Thad Cochran National Warmwater Aquaculture Center, Mississippi Agriculture and Forestry Experiment Station, Mississippi State University, Post Office Box 197, Stoneville, Mississippi 38776, USA.
 

Multiple-batch production is the most widely practiced method of raising channel catfish. Producers are increasingly adopting intensified production practices in multiple-batch systems by increasing stocking density and aeration rates as a means to improve cost efficiencies. Proven stocking recommendations are required for the efficient implementation of recent developments in multiple-batch production. Twelve 0.4-ha ponds were understocked with 17,484, 20,612, and 26,124 fingerlings/ha (mean weight = 40 g/fish) over equal weights of carryover fish (0.46 kg/fish @ 4,589 kg/ha). Fish were fed once daily to apparent satiation with a 28% protein floating feed and aerated with a single 7.4-kW electric paddlewheel aerator. Density-dependent significant differences were absent for gross, net, daily-net yields, marketable yields (≥0.54 kg), growth (g/d), and survival. Sub-marketable yield (<0.54 kg) and feeding rate increased significantly with increased understocking density. Economic analysis revealed increased breakeven prices and diminished net returns with increased stocking density when sub-marketable fish were not considered as revenue. These differences in production costs and profits among the three treatments became minimal when sub-marketable fish were included as revenue. All three density treatments attained positive annual net cash flows. This study validates channel catfish understocking densities of 17,000-26,000 fish/ha to improve cost efficiency in intensively aerated, multiple-batch production systems.