CULTIVATION OF TIGER PRAWNS, PENAEUS-MONODON FABRICIUS, 1798 (DECAPODA, NATANTIA) IN HAINAN, PR CHINA

The yield as well as the occurrence of various diseases in commercial, semi-intensive, closed-system shrimp cultivation ponds in Wanning Cou nty, Hainan Province, P. R. China, has been correlated with a large nu mber of pond, water quality, food, and water addition (fertilizer) par ameters. It appears that reduced yields and the occurrence of diseases are closely associated with the age of a pond, the substrate, and the water quality (especially low salinities, low pH values, relatively l ow nitrate concentrations, and high ammonia-N and phosphate concentrat ions). To cure the diseases, the use of chemicals, various inorganic s alts, and various kinds oi antibiotics, appeared to be ineffective.