Abstract
Channel catfish from two domestic strains and two wild strains, and intraspecific crosses between strains were evaluated under aquacultural conditions. Growth studies were conducted in tanks, cages, and communal ponds. Reproductive characters including spawning time, egg size, hatchability, and percent deformed fry were evaluated for each strain or cross. Correlations were also determined for reproductive characters and growth characters. Different strains of channel catfish had different peak spawning periods indicating possible genetic control. Hatchability was an extremely variable trait and no differences among strains or crosses could be demonstrated. Environmental factors may have overshadowed genetic factors affecting the frequency of deformed fry. No differences among strains or crosses could be demonstrated for the percent of deformed fry. Deformed individuals had lower survival rates in ponds. The total weight of a spawn and the number of eggs/spawn were positively correlated to the weight of the female broodfish; egg weight was negatively correlated to the weight of the female broodfish. Egg weight was not correlated to hatchability or initial weight. However, initial weight was correlated to total weight during the first 60 days of growth in tanks. Domestic strains had superior growth rates compared to wild strains in ponds and cages. No heterosis for growth rates in ponds and cages could be demonstrated for crosses between domestic strains or crosses between domestic and wild strains. There were no significant differences for percent survival in ponds and cages, and no consistent differences for dress-out percent. Initial variation for length and weight among strains or crosses were reduced during the growing season.
Broussard, Meryl Claude (1979). The evaluation of four strains of channel catfish, Ictalurus punctatus, and intraspecific hybrids under aquacultural conditions. Texas A&M University. Texas A&M University. Libraries. Available electronically from
https : / /hdl .handle .net /1969 .1 /DISSERTATIONS -685136.