Costs of winter feeding of channel-blue ([female] Ictalurus punctatus x [male] Ictalurus furcatus) hybrid catfish.

摘要

Previous research has shown that winter feeding is beneficial in preventing weight loss and maintaining catfish health. Although several studies suggest the importance of winter feeding of channel catfish, Ictalurus punctatus, less is known about optimal winter feeding strategies for channel-blue hybrid catfish ([female] Ictalurus punctatus x [male] Ictalurus furcatus). Three winter feeding treatments (unfed, fed daily, and fed based on temperature-threshold feeding) were each assigned randomly to four replicate 0.10-ha earthen ponds. All ponds were stocked with large channel-blue hybrid catfish (0.96+or-0.40 kg) at the rate of 3409 kg/ha and fed using a slow-sink 28% protein pelleted feed. The two feeding treatments showed significantly greater mean weight at harvest, gross yield, and growth rates than the unfed fish after the 113-d winter trial. Partial budget analysis indicated that additional costs incurred from the additional feed, fuel, and labor costs over the winter in fed treatments offset the additional revenue from daily winter feeding. However, in the temperature-threshold feeding treatment, additional costs were similar to additional revenues when 10-yr average prices were used. Results were sensitive to feed prices and spring catfish prices with positive net benefits from winter feeding at fish prices above $1.58/kg and feed prices below $0.286/kg.