Application of Antibiotics in the Cultivation of Dungeness Crab, Cancer Magister

Abstract

In static cultivation of Cancer magister zoeae, duration of antibiotic treatment, effectiveness of various antibiotics, and therapeutic pretreatment of the live food were evaluated. Periodic treatment with antibiotics was necessary to maintain high zoeal survival, the greatest benefit occurring during the early zoeal period. Low concentrations (1–10 mg/L) of chloramphenicol were equally or more successful than 100 mg/L streptomycin plus 100 mg/L penicillin. Kanamycin (100 mg/L) and neomycin (50 mg/L) appeared toxic to the zoeae. Successful antibiotic treatment did not alter the development and increased the weight of cultivated zoeae, although these were all lighter than captured crabs of the same apparent age. There was indication that elimination of bacterial epibionts with antibiotics restricted the attachment of other microbial epibionts. Key words: aquaculture, mariculture, epibionts, Crustacea epibionts, zoeal survival, Artemia salina, antibiotics