Fish Hatchery Management - fisheries & aquaculture

FISH HEAI-TH MANAGHMI]N'I 30:lof the best possible environmental conditions, and avoidance of overcrowdingfish.External infections of columnaris may be treated with:(t) Dlquat (not registered by the Food and Drug Administration) at U.4to 16.8 parts per million (2 4 parts per million active cation) for t hourdaily on 3 or 4 consecutive days.(2) T"..u*ycin (registered by the Food and Drug Administration) as aprolonged bath at l5 parts per million active ingredient (0.57 gram per 10gallons; 4.25 grams per l0 cubic feet) for 24 hours.(3) Furanace for trout and salmon (not registered by the Food and DrugAdministration) as a bath at I part per million active ingredient (0.03ugram per 10 gallons; 0.283 gram per l0 cubic feet) for 5-10 minutes, or at0.1 part per million active ingredient (0.0038 gram per 10 gallon; 0.0283gram per 10 cubic feet) for an indefinite period.(4) Copp". sulfate (registered by the Food and Drug Administration) at0.5 part per million for pond treatments.(5) Potassium permanganate (registered by the Food and Drug Administration),the most effective pond treatment for external columnaris infectionsin warmwater fish, at the rate of 2 parts per million (5.4 pounds peracre-foot). If the color changes in less than l2 hours it may be necessary torepeat the treatment.Internal infections o[ columnaris may be treated with Terramycin or sulfonamides,both registered by the Food and Drug Administration.(1) For channel catfish and other warmwater fish that will take artificialfood, provide medicated feed that will deliver 2.5 3.5 grams Terramycinper 100 pounds of fish per day for 7 to l0 days. For fish being fed 3'll oftheir body n'eight daily, it is necessary to have U3.3-116.7 grams Terramycinper 100 pounds of food. Under no circumstances should the treatmenttime be less than 7 days. For salmonids, Terramycin given orally in thefeed at a rate of 3.5 grams per 100 pounds fish per day for up to l0 days isvery effective in early as well as advanced outbreaks.(2j For salmonids, sulfamerazine and sulfamethazine can be given orallyin the feed at a rate of 5 to 10 grams per 100 pounds of fish per day, butthey are less effective than other drugs.r,l1I)Ll NCr-!. l)r sr.rAS!lPeduncle Disease is the same condition knorvn as coldwater or lowtemperaturedisease. Lesions appear on the fish in similar locations, systemicflexibacteria are present, and the disease occurs at low water temperaturesin the range of 45'to50'F. Affected fish become darkened, and lesionsmay develop on the caudal peduncle or on the isthmus anterior to