Studies on diseases of walking catfish and water quality in circular concrete ponds in Phuket
1995
Kannika Kanjanachatree (Prince of Songkla Univ. Phuket Campus, Phuket (Thailand))
Four tanks (height=1 m, diameter=3 m) Contained 7 tons of water each. Tank no.1 was the control which contained no fish but water quality was analyzed. Tanks 2, 3 and 4 contained 200, 300 and 400 catfish per tank, respectively, of 3-7 cm in lenght. Food, of 40 percent protein was given. After 2 months some of the catfish were diseased. The results of microbiological and biochemical analysis revealed that they were infected with Aeromonas hydrophila. An early morning treatment of Oxytetracycline concentrate (20 ppm) was used. To treat the external parasites Dactylogyrus sp, Ichthoyphthirius sp. and Trichodina sp. (infecting skin and gills), Formalin at 30 ppm was used. At the conclusion of the 6 month experiment 18.5 percent of the catfish in tank no.2 (200 catfish/ton) died, 28.5 percent in tank no.3 (300 catfish/ton) and 33 percent in tank no.4 (400 catfish/ton) Water quality was analyzed every week and a positive correlation was found between temperature and death rate and nitrite level and death rate. The above results indicate that 200 catfish/ton yields the best harvest.
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