Channel catfish

Catfish are not a major contributor to aquaculture production globally, but the channel catfish industry dominates United States aquaculture. United States catfish production, primarily channel catfish, was 209,090 metric tons in 1992 (4). 

Problems associated with excessive levels of nutrients and unwanted nuisance species have already been mentioned. There are cases in which intentional fertilization is used by aquaculturists in order to produce desirable types of natural food for the species under culture. Examples of this approach include inorganic fertilizer appHcations in ponds to promote phytoplankton and zooplankton blooms that provide food for young fish such as channel catfish, the development of algal mats through fertilization of milkfish ponds, and the use of organic fertilizers (from Hvestock and human excrement) in Chinese carp ponds to encourage the growth of phytoplankton, macrophytes, and benthic invertebrates. In the latter instance, various species of carp with different food habits are stocked to ensure that all of the types of natural foods produced as a result of fertilization are consumed. 

Young animals may be fed several times daily. Examples include the standard practices of feeding fry channel catfish every three hours and young northern pike as frequently as every few minutes. Keeping carnivorous species such as northern pike satiated helps reduce the incidence of cannibalism. 

Species such as carp, salmon, trout, channel catfish, and tilapia have been bred for many generations in captivity though they usually differ httle in appearance or genetically from their wild counterparts. A few exceptions exist, such as the leather carp, a common carp strain selectively bred to produce only one row of scales, and the Donaldson trout, a strain of rainbow trout developed over numerous generations to grow more rapidly to larger size and... 

The mode of action has not yet been elucidated but the manufacturer states that it probably behaves like the herbicide triflurolin and its congeners. These materials inhibit cell division by binding to tubuHn thereby internipting micro-tubule development. This, in turn, stops spindle fiber formation essential to mitosis and cell division. Experiments with C-labeled Prime+ show that it is acutely toxic to fish with estimated LC q (96 h) of less than 100 ppb for rainbow trout and bluegiU. sunfish. However, channel catfish did not exhibit any toxic response at the maximum attainable water concentration (10). 

Environmental Impact of Ambient Ozone. Ozone can be toxic to plants, animals, and fish. The lethal dose, LD q, for albino mice is 3.8 ppmv for a 4-h exposure (156) the 96-h LC q for striped bass, channel catfish, and rainbow trout is 80, 30, and 9.3 ppb, respectively. Small, natural, and anthropogenic atmospheric ozone concentrations can increase the weathering and aging of materials such as plastics, paint, textiles, and mbber. For example, mbber is degraded by reaction of ozone with carbon—carbon double bonds of the mbber polymer, requiring the addition of aromatic amines as ozone scavengers (see Antioxidants Antiozonants). An ozone decomposing polymer (noXon) has been developed that destroys ozone in air or water (157). 

Intensive or extensive culture of aquatic animals requires chemicals that control disease, enhance the growth of cultured species, reduce handling trauma to organisms, improve water quality, disinfect water, and control aquatic vegetation, predaceous insects, or other nuisance organisms. The aquacultural chemical need for various species have been described for rainbow trout, Oncorhjnchus mjkiss (1) Adantic and Pacific salmon, Salmo and Oncorhjnchus sp. (2) channel catfish, Ictaluruspunctatus (3) striped bass, Morone saxatilis (4) milkfish, Chanos chanos (5) moUusks (6) penaeid (Penaeus sp.) shrimp (7) and a variety of other marine species (8). 

Yang, H. and Wang, Y. (2009). Effects of concentration on nanostructural images and physical properties of gelatin from channel catfish skins. Food Hydrocolloids 23, 577-584. 

Rainbow trout and channel catfish were exposed to a nominal concentration of 0.02 mg/L of niclosamide for a period of approximately 12 h. Samples of fillet tissue were collected from each fish species before treatment and at 6, 12, 18, 24, 48, 96, and 192 h after exposure. The fish were dissected, homogenized, extracted, and analyzed by HPLC [75],... 

Channel catfish, Ictalurus punctatus, fingerlings Exposed for 96 h at 16 mg CaC03/L ... 

Straus, D.L. and C.S. Tucker. 1993. Acute toxicity of copper sulfate and chelated copper to channel catfish Ictalurus punctatus. Jour. World Aquacult. Soc. 24 390-395. 

Fish may be more resistant to lead than mammals. For example, isolated liver hepatocytes of channel catfish were about 40 times more resistant to lead than rat liver hepatocytes as judged by ALAD inhibition (Conner and Fowler 1994). 

Conner, E.A. and B.A. Fowler. 1994. Biochemical and immunological properties of hepatic delta-aminolevulinic acid dehydratase in channel catfish (Ictalurus punctatus). Aquat. Toxicol. 28 37-52. 

Adults Channel catfish, Ictalurus punctatus LC77 (10 d) 1000 19... 

Channel catfish, Ictalurus punctatus from fertilization through day 4 posthatch 38 (18-68) pg/L LC10 28... 

Rice, C.D., M.M. Banes, and T.C. Ardelt. 1995. Immunotoxicity in channel catfish, Ictalurus punctatus, following acute exposure to tributyltin. Arch, Environ. Contam. Toxicol. 28 464-470. 

Rice, C.D. and L.E. Roszell. 1998. Tributyltin modulates 3,3, 4,4, 5-pentachlorobiphenyl (PCB-126)-induced hepatic CYP1A activity in channel catfish, Ictalurus punctatus. Jour. Toxicol. Environ. Health 55 A 197-212. 

---