Location: Warmwater Aquaculture Research UnitTitle: A non-lethal means to identify spermiating D&B strain of blue catfish, Ictalurus furcatus
Submitted to: Aquaculture North America
Publication Type: Trade Journal
Publication Acceptance Date: 1/28/2016
Publication Date: 3/15/2016
Citation: Chatakondi, N.G., Davis, K.B., Peterson, B.C. 2016. A non-lethal means to identify spermiating D&B strain of blue catfish, Ictalurus furcatus. Aquaculture North America. 7(2):6-7.
Interpretive Summary: US farm-raised catfish industry is leaning towards raising hybrid catfish in ponds. Blue catfish, the male parent of the hybrid catfish is sparingly improved due to lack of domestication and late puberty. It is often difficult to identify higher sperm producing blue catfish without sacrificing the fish. Five independent physio-morphometric factors of 142 individual blue catfish mature males were measured to predict estimated sperm production by forward step-wise regression analyses. Of the five criteria, subjective stage of gonadal maturity of blue catfish described in the study predict estimated sperm production in blue catfish. This criteria is simple, cheap and timely to estimate sperm production in blue catfish under farm conditions.
Technical Abstract: US farm-raised catfish production was 334 million pounds in 2013, the first annual increase documented in a decade. This positive development is due to the increased adoption of channel x blue hybrid catfish in the industry. Research and development efforts to improve the genetics of channel catfish, husbandry, develop effective ovulating hormones, stress reduction protocols and improved hatching conditions has substantially increased the production efficiency of hybrid catfish. Heterotic effects of hybridization made it possible for hybrid catfish to perform better than the parental species, tolerate stressors and common diseases resulting in higher survival and production levels. Despite these improvements in hybrid catfish fry production, blue catfish – the male parent of the hybrid catfish has been sparingly improved due to lack of domestication and late puberty. The testes of blue catfish are elongated villiform lobes and hence sperm cannot be expressed from a live blue catfish. Sexually mature male blue catfish (5 years old) have to be sacrificed, testes removed to prepare sperm solution and quantified to estimate sperm production. The goal of the study was to identify higher sperm producing blue catfish that will likely lead to improve the efficiency of hybrid catfish fry production in hatcheries.