Research Project: Improving the Productivity and Quality of Catfish Aquaculture

Location: Warmwater Aquaculture Research Unit

2022 Annual Report

Objectives
Objective 1. Enhance selection of channel and blue catfish broodstock for economically important traits. Sub-objective 1.1. Continue selection for increased growth rate and carcass yield in channel catfish, blue catfish and channel catfish x blue catfish hybrids, and establish a selected line of blue catfish to produce improved broodstock. Sub-objective 1.2. Determine magnitude of genetic variation and evaluate potential for including additional traits in channel and blue catfish selection indices. Sub-objective 1.3. Characterize structural variation in the channel and blue catfish genomes and examine the potential for this information to improve the accuracy of estimated breeding values. Objective 2. Improve the efficiency of reproduction for purebred and hybrid catfish. Sub-objective 2.1. Identify and test reproductive pheromones in channel and blue catfish. Sub-objective 2.2. Evaluate the formulation of mammalian Luteinizing Hormone Releasing Hormone analog to improve ovulation and hatching success to improve the efficiency of hybrid catfish embryo production. Sub-objective 2.3. Determine impact of broodfish nutritional strategies on maturation and reproductive performance of channel catfish to maximize hatching success and hybrid catfish fry production. Objective 3. Increase efficiency of warmwater aquaculture by developing and improving production systems and management practices. Sub-objective 3.1. Model split-pond ecosystem dynamics to optimize design and performance. Objective 4. Improve catfish product quality by identifying and managing pre-harvest factors that affect the quality of catfish products. Sub-objective 4.1. Isolate and identify geosmin-producing species of cyanobacteria from catfish aquaculture ponds and determine the seasonal occurrences of blooms of these noxious cyanobacteria species. Sub-objective 4.2. Determine the efficacy of using sodium carbonate peroxyhydrate (SCP) in managing undesirable blooms of cyanobacteria in west Mississippi catfish ponds. Sub-objective 4.3. Determine the effects of pond culture systems on fillet flavor and texture of hybrid catfish.

Approach
In order to enhance selection of channel and blue catfish broodstock for economically important traits we will continue selection for increased growth rate and carcass yield in channel catfish, blue catfish, and channel x blue catfish hybrids, and establish a selected line of blue catfish to produce improved broodstock; determine the magnitude of genetic variation and evaluate potential for including additional traits in channel and blue catfish selection indices; and characterize structural variation in the channel and blue catfish genomes and examine its potential to improve the accuracy of estimated breeding values. In order to improve catfish reproductive efficiency, we will identify reproductive pheromones of channel and blue catfish; evaluate the formulation of mammalian Luteinizing Hormone Releasing Hormone analog to improve ovulation and hatching success to improve the efficiency of hybrid catfish embryo production; and determine the impact of broodfish nutritional strategies on maturation and reproductive performance of channel catfish to maximize hatching success and hybrid catfish fry production. In order to increase the efficiency of warmwater aquaculture by developing and improving production systems and management practices, we will model split-pond ecosystem dynamics to optimize system design and performance. In order to improve catfish product quality by identifying and managing pre-harvest factors that affect the quality of catfish products, we will isolate and identify geosmin-producing species of cyanobacteria from catfish aquaculture ponds and determine the seasonal occurrences and blooms of these noxious cyanobacteria species; determine the efficacy of using sodium carbonate peroxyhydrate (SCP) in managing undesirable blooms of cyanobacteria in west Mississippi catfish ponds; and determine the effects of pond culture system on fillet flavor and texture of hybrid catfish.

Progress Report
This project replaces project 6066-31000-016-000D, "Biophotonics - The Application of Novel Imaging Methodologies to Livestock Production Research." The catfish industry is the largest sector of U.S. aquaculture but most farms are small and don’t have the resources or technology to conduct their own genetic improvement programs. Therefore, ARS researchers in Stoneville, Mississippi, conduct research to develop genetically superior channel and blue catfish germplasm for release to the producers. Genetic selection is a continuous process and ARS researchers currently continue to select for increased growth rate and meat yield in a line of channel catfish (Delta Select line) and two lines of blue catfish (the Rio Grande and Delta Elite lines). In 2020, three catfish lines were released to owners of catfish hatcheries, who have provided favorable reports on their production, particularly for the Delta Select channel catfish line. Several hatchery operators who provide fingerlings to a large portion of the industry have indicated plans to produce only the Delta Select line. We are currently evaluating other economically important traits for possible inclusion in the genetic improvement program. At the request of industry, additional releases of germplasm are planned for the winter of 2023 or 2024. Currently, U.S. catfish production consists of 30-40% channel catfish and 60-70% blue x channel hybrid catfish. ARS researchers developed and tested a synthetic peptide useful as a spawning agent for inducing oocyte maturation and ovulation in channel catfish females for hybrid catfish production and provided scientific support for the production and commercialization of the peptide. Producers first used the peptide in 2021, and its success led every hybrid catfish producer to use the peptide during the 2022 spawning season. The peptide’s commercial vendor estimated that 80% of the hybrid catfish produced in 2022 resulted from its use. A field study was conducted on a commercial farm to characterize the macroinvertebrate community of catfish production ponds throughout the production season. A prototype of a snail trap was created to evaluate a passive method of monitoring populations of parasite-vector snail species and better inform treatment regimes. The effects of rotenone use on phytoplankton, zooplankton, and macroinvertebrate communities was evaluated and suggest little disturbance, as well as rapid recovery in each group. The lethal concentrations (LC50s) of copper sulfate for ghost ramshorn snail eggs, juveniles, and adults were determined through lab studies. These LC50 values will be used to explore snail treatment protocols that reduce the risk of copper toxicity to catfish in ponds. As catfish production has shifted from channel catfish to blue x channel hybrids, it is important to understand effects of potential pathogens that may affect hybrids that were not problematic for channel catfish. Blue catfish alloherpesvirus (BCAHV) is such a pathogen and ARS researchers in Stoneville, Mississippi, along with collaborators from Mississippi State University, reported that young channel catfish were resistant to BCAHV but blue and hybrid catfish were susceptible and experienced significant mortalities following experimental challenges. Fish mortalities were higher in cooler water temperatures and at high fish densities. A cell culture line was developed that allowed propagation of BCAHV and will be a valuable research tool to allow more detailed studies BCAHV. Future studies will focus on control of BCAHV through the development of vaccines and environmental manipulations. This research will benefit U.S. catfish producers given the shift to hybrid catfish production in the industry.

Accomplishments

Review Publications
Stilwell, J., Griffin, M., Waldbieser, G.C., Stanton, J., Ware, C., Leary, J., Khoo, L., Wise, D., Camus, A. 2022. Myxozoan community composition and diversity in clinical cases of proliferative gill disease in mississippi catfish aquaculture. Journal of Parasitology. 108(2):132–140. https://doi.org/10.1645/21-57.
Richardson, B.M., Mischke, C.C., Rosser, G.T., Woodyard, E.T., Ware, C., Wise, D.J., Griffin, M.J. 2022. Non-specific activation of Henneguya ictaluri actinospores. North American Journal of Aquaculture. https://doi.org/10.1002/naaq.10242.
Schrader, K. 2022. Impact of diuron applications to commercial catfish ponds on musty-odor cyanobacteria, musty off-flavor compound concentrations, and channel catfish fillet flavor quality. North American Journal of Aquaculture. 84:149-155. https://doi.org/10.1002/naaq.10225.
Quiniou, S., Crider, J., Felch, K.L., Bengten, E., Boudinot, P. 2022. Interferons and Interferons receptors in the Channel catfish, Ictalurus punctatus. Fish and Shellfish Immunology. https://doi.org/10.1016/j.fsi.2022.02.019.
Crider, J.D., Quiniou, S., Felch, K.L., Showmaker, K., Bengten, E., Wilson, M. 2021. A comprehensive annotation of the channel catfish (Ictalurus punctatus) T cell receptor alpha/delta, beta and gamma loci. Frontiers in Immunology. https://doi.org/10.3389/fimmu.2021.786402.
Ott, B.D., Torrans, E.L., Griffin, M.J., Allen, P.J. 2022. Quantitative PCR assays to measure the HPI axis neuropeptides corticotropin-releasing factor (CRF) and urotensin I (UI) in channel catfish (Ictalurus punctatus). Aquaculture. 555:738253. https://doi.org/10.1016/j.aquaculture.2022.738253.
Lopez-Porras, A., Griffin, M.J., Ware, C., Richardson, B.M., Greenway, T.E., Rosser, T.G., Aarattuthodiyil, S., Wise, D.J. 2022. Cross-protection efficacy of a live-attenuated Edwarsiella ictaluri vaccine against heterologous Edwardsiella piscicida isolates in channel and channel x blue hybrid catfish. Journal of Fish Diseases. https://doi.org/10.1111/jfd.13623.
Woodyard, E.T., Rosser, T.G., Stillwell, J.M., Camus, A.C., Khoo, L.H., Waldbieser, G.C., Lorenze, W.W., Griffin, M.J. 2022. New data on Henneguya postexilis Minchew, 1977, a parasite of channel catfish Ictalurus punctatus, with notes on resolution of molecular markers for myxozoan phylogeny. Systematic Parasitology. 99(1):41-62. https://doi.org/10.1007/s11230-021-10015-3.
Heckman, T.I., Shahin, K., Henderson, E.E., Wright, A., Waldbieser, G.C., Griffin, M.J., Soto, E. 2022. Development and efficacy of Streptococcus iniae live-attenuated vaccines in Nile tilapia, Oreochromis niloticus. Fish and Shellfish Immunology. 121:152-162. https://doi.org/10.1016/j.fsi.2021.12.043.
Schrader, K., Green, B.W., Rawles, S.D., Mcentire, M.E. 2022. Effects of feed applications with various phosphorus concentrations on the abundance of cyanobacteria and common off-flavor compounds in hybrid striped bass aquaculture ponds. Journal of Applied Aquaculture. https://doi.org/10.1080/10454438.2022.2086839.
Armwood, A.R., Griffin, M.J., Richardson, B.M., Wise, D.J., Ware, C., Camus, A.C. 2022. Pathology and virulence of edwardsiella tarda, edwardsiella piscicida, and edwardsiella anguillarum in channel (ictalurus punctatus), blue (ictalurus furcatus), and channel (female) x blue (male) hybrid catfish. Journal of Fish Diseases. 00:1-16. https://doi.org/10.1111/jfd.13691.
Dharan, V., Aarattuthodi, S., Khoo, L., Bosworth, B.G. 2022. Establishment and charaterization of a cell line from ictalurid catfish. Journal of the World Aquaculture Society. 53:620-633. https://doi.org/10.1111/jwas.12869.