Fred P. Meyer

Teratological and other effects of malachite green on development of rainbow trout and rabbits

Abstract Malachite green oxalate caused significant developmental abnormalities when administered to eggs of rainbow trout Salmo gairdneri and to pregnant New Zealand white rabbits Oryctolagus cuniculus. Treatment of rainbow trout eggs with malachite green caused deformities of larvae at rates three to five times that observed in untreated lots. All dose levels affected fetal development of rabbits. At the dosages given, the incidence of anomalies caused by malachite green was about half that observed in thalidomide-treated positive controls and two to three times that in untreated controls. Abnormalities noted in fish were primarily of the spine and skull. In rabbits, anomalies most frequently involved the skeleton, liver, heart, and kidneys. Some fetal toxicity was observed. Received March 28, 1983 Accepted August 8, 1983

Status of Fishery Chemicals in 1985

Abstract A summary list of registered or approved products is provided for fishery uses, effective June 1985. The current status of efforts to register others and a discussion of the need for new products is presented.

Communications: Solutions to the Shortage of Approved Fish Therapeutants

Abstract Thirty-nine compounds are now registered or approved for aquatic or fisheries uses, of which only eight are for the treatment of diseases. Three antibacterials are approved, but only two, Terramycin and Romet 30, are available. Despite a rapidly expanding volume of literature about the effectiveness of compounds against fish pathogens, virtually no researchers have conducted the types of studies needed for approval of these compounds by the U.S. Food and Drug Administration. There is a pressing need for the development of data on pharmacokinetics, residue dynamics, withdrawal periods, metabolites, and environmental fate for compounds with potential fisheries applications. We do not need more candidate drugs. Researchers should focus their studies on compounds that have good efficacy, are available in veterinary or feed formulations and, if possible, are already approved for use in another animal species. If a drug is available only for human use, most sponsors will not support its use in aquacult...

Re-Registration of Rotenone: A State/Federal Cooperative Effort

Abstract Rotenone is an effective fish toxicant used by virtually all states to manage fish populations. In response to an allegation that rotenone might cause mammary tumors, the U.S. Environmental Protection Agency, in 1976, announced that it was considering listing rotenone as an unsafe substance. To determine if these allegations were correct, the U.S. Fish and Wildlife Service, in concert with the International Association of Fish and Wildlife Agencies, embarked on an extensive research effort. The project was funded in part with Federal Aid in Sport Fish Restoration administrative funds, extended over 6 years, and cost nearly

Sea Lamprey Control Techniques: Past, Present, and Future

3,000,000. Data developed from this effort indicate that, if used according to its label instructions, rotenone is a safe and effective product.

Winter Harvest of Bluegills in 1976-1977 from Lake Onalaska, Wisconsin

Early attempts at controlling the sea lamprey (Petromyzon marinus) in the Great Lakes in the 1950s centered on a variety of mechanical and electrical devices to prevent migration of adults into tributary streams to reproduce. Although some of the devices were effective, it became obvious that barriers alone were not an adequate solution to the lamprey predation problem. Researchers screened over 6,000 chemicals before they found 3-trifluoromethyl-4-nitrophenol (TFM), a toxicant to which sea lamprey larvae and adults are particularly sensitive. Bayer 73 enhances lampricidal activity when used in combination with TFM. In 1970, the U.S. Environmental Protection Agency (EPA) required additional studies to support continued use and registration of TFM. Most of these studies have been completed, but the EPA could cancel the existing registration in the event of unforeseen problems or hazards associated with its use. Therefore, the Great Lakes Fishery Commission continues to support research on lamprey control techniques, such as new formulations of TFM and Bayer 73, sterile male techniques, and attractants and repellents. Development of an integrated management program to combat the sea lamprey is being planned. This concept involves the systematic application of multiple techniques in a way that will exert maximum impact on the sea lamprey. Possible programs may involve chemical, biological, and physical control techniques, each of which would be subject to its own registration or regulatory requirements.

Aquaculture disease and health management.

Abstract A winter creel census of bluegills (Lepomis macrochirus) conducted on Pool 7 (Lake Onalaska, Wisconsin) on the Upper Mississippi River in 1976-1977 used a half-day sampling schedule and car counts to estimate angler numbers. The calculated harvest was based on these counts plus data from interviews with 3,429 anglers. The total estimated harvest for the 17-week fishery (22 November-18 March) was 233,061 bluegills taken by 25,402 anglers during 96,519 hours of fishing (2.41 fish per hour). Of the bluegills harvested, 52% were taken during the first 5 weeks of the fishing season. Average length and weight of bluegills harvested was 178 mm and 136 g, respectively; total estimated weight of the catch was 31,696 kg.