Submitted to: International Aquaculture Meeting
Publication Type: Abstract Only
Publication Acceptance Date: November 24, 2003
Publication Date: March 1, 2004
Citation: Green, B.W. 2004. Use of threadfin shad as a forage species in channel catfish production ponds. Aquaculture 2004 Book of Abstracts. p. 237.
Interpretive Summary: Not Required.
As pond bank prices of channel catfish (Ictalurus punctatus) continue at low levels, farmers are seeking ways to increase production efficiency and reduce costs. One strategy under consideration is to reduce feed utilization as a means to lower production costs. Threadfin shad (Dorosoma petenense) have been stocked in channel catfish production ponds in an effort to control phytoplankton biomass. However, because of their smaller size threadfin shad also could serve as forage fish for channel catfish in production ponds, thereby allowing a reduction in either feed quantity offered to fish or in feeding frequency. The objective of the present study was to determine if channel catfish feeding frequency could be reduced to once every three days compared to daily in ponds co-stocked with threadfin shad.
Twelve 0.1-ha ponds were used for this completely randomized design in factorial arrangement study. Factors tested were presence/absence of threadfin shad and feeding frequency of daily or every third day. Adult, pre-spawn threadfin shad were stocked at 408 kg/ha and allowed three weeks to spawn. Each pond then was stocked with stocker channel catfish (average 0.35 kg) at 5,040 kg/ha and fingerling catfish (14,820/ha, average weight 27 g). Fish were fed a 32% protein extruded feed either daily or every third day. Ponds were equipped with 0.37-kW electric paddlewheel aerator, which were operated as needed to maintain 3.5 mg/L dissolved oxygen. Ponds were harvested by draining and total weight of each class of fish determined. Mean individual weight of fish in each size class was determined by individually weighing 100 fish per pond. Gross yield, survival and FCR were measured for stocker and fingerling catfish.