Drugschemicals used in aquaculture Feed additives Sulfonamides Sulfamerazine

Drugs/chemicals used in aquaculture Feed additives (Sulfonamides) – Sulfamerazine (fish grade) and Romet-30 • Effective for bacterial infections • • – Toxicity may occur • Kidney damage (drug crystal formation in renal tubules) • Clinical signs – bloating/dropsy (stomach full of water) • • Commercial availability in feed has limited many problems

Drugs/chemicals used in aquaculture Sulfonamides (continued) – Sulfamerazine (fish grade) • No longer available – Romet-30 • Suggested dose (furunculosis) – 50 mg/kg fish/day for 5 to 7 days • Also effective for ESC •

Drugs/chemicals used in aquaculture Terramycin (oxytetracycline) – TM 50 – Generally drug of choice in aquaculture – Recommended dose – 55 -83 mg/Kg fish/day for 10 days – Effective against gram neg. bacteria (BKD? ) • ERM, Furunculosis, CWD, etc. – – Should not be fed on prophylactic basis! • Resistance to oxytetracycline can occur in most bacterial fish pathogens (Meyer and Schnick 1989)

Drugs/chemicals used in aquaculture Therapeutants added to water – Methods • Static bath – most reliable for raceways/tanks/troughs • Constant flow – safe and can be used in most situations when fish reared in running water • Prolonged – – Chemicals • Formalin – Most widely used agent in fish culture – (solution contains 37% formaldehyde in water)

Drugs/chemicals used in aquaculture • Chemicals (cont. ) – Quaternary Ammonium compounds • Benzalkonium chloride/Hyamine • • Now only limited use in food fish – Potassium Permanganate • Strong oxidizing agent •

Drugs/chemicals used in aquaculture • Chemicals (cont. ) – Copper Sulfate • Algaecide/bactericide/parasiticide • • Can produce kidney necrosis, destruction of hematopoietic tissue, increased liver fat and inhibition of digestive enzymes. – Na. Cl (salt) • Most overlooked treatment • Can be very effective • • 3% recommended if possible (10 -30 min)