FISH Hl.Al.lH MANA(;EMENI" 279 



Hyamine 3500 is a standardized quaternary ammonium compound con- 

 taining a high percentage of desirable components and very few undesir- 

 able ones. It has proven very satisfactory for the treatment of external 

 bacterial infections of trout and salmon. Hyamine 3500 is a 50% solution 

 and can be used directly, or first diluted to a 10"() solution. In either case, 

 Hyamine 3500 should be used at a final dilution of 2 parts per million 

 (based on active ingredients) for 1 hour. 



In the case of Roccal, shipments may vary in toxicity to both the fish 

 and the bacteria. Whenever a new supply is received, it should be tested 

 on a few fish before being used in a production unit. 



Some quaternary ammonium compounds, such as Roccal, have been 

 used to treat external bacterial infections in salmonids for many years with 

 varying degrees of success. Their big drawback has been the variable com- 

 position of different lots; they gave good control sometimes, but killed fish 

 at others. 



The quaternary ammonium compounds have seen little use in warmwater 

 fish culture, except for the disinfection of equipment, tanks, and troughs. 

 However, these compounds are excellent bactericides and should be effec- 

 tive as tank treatments in controlling external bacterial infections of 

 catfish. 



TERRAMYCIN^ 



Terramycin (oxytetracycline) (registered by the Food and Drug Adminis- 

 tration) is a broad-spectrum antibiotic widely used to control both external 

 and systemic bacterial infections of fish. It is available in many formula- 

 tions, both liquid and powder. 



As a prolonged-bath treatment in tanks, it is used at 15 parts per million 

 active ingredient (0.57 gram active ingredient per 10 gallons; 4.25 grams 

 active ingredient per 10 cubic feet) for 24 hours. The treatment may have 

 to be repeated on 2 to 4 successive days. 



External bacterial infections, such as columnaris and bacterial gill 

 disease in salmonids, often are treated successfully in troughs and tanks 

 with '^- to 1-hour exposures to the Terramycin Soluble Powder in solution. 

 One successful treatment uses 1.75 grams of formulation (as it comes from 

 the package) per 10 gallons of water. In tanks and troughs, the technique 

 requires lowering the water below the normal volume, adding the lerramy- 

 cin (dissolved in some water), allowing the water to refill to the desired lev- 

 el, and then turning off the flow. Aeration must be provided. Foaming can 

 be a problem. After the proper length of time, the normal water flow is 

 turned back on and allowed to flush the unit. 



Where small numbers of large or valuable fish are involved, Terramycin 

 can be injected intraperitoneally or intramuscularly at 25 milligrams per 

 pound of body weight. 



