Summary: | 碩士 === 國立臺灣海洋大學 === 水產養殖學系 === 92 === Abstract
The Kuruma shrimp Marsupenaeus japonicus juveniles reared in the salinity of 12, 18, 26 and 34 ‰ for 126 days. The survival rate were higher in the shrimp reared in salinity of 18 and 26 ‰ and the lowest in 12 ‰.The weight gain and body length increase of shrimp cultured in 26 ‰ and 34 ‰ were significantly higher than those of shrimp culture in 12 ‰ and 18 ‰. The isosmotic point was 821.6 mOsm/kg (equivalent to 27 ‰). The intermolt period of shrimp reared in 12 ‰ was significantly shorter during the first four molting. The moisture content of shrimp was inversely related to salinity whereas, hemolymph osmolality and ion concentration increased directly with salinity.
Hemolymph osmolality and hemolymph ion concentration were examined when M. japonicus were transferred from 34 ‰ to 18, 26, 34 (control) and 42 ‰ after 0, 1, 3, 6, 12, 24 and 48 h. Hemolymph osmolality and ion concentrations increased directly with salinity level. The isosmotic point was 862.1 mOsm/kg (equivalent to 28 ‰) and 365.7 mmol/l for osmolality and chloride, respectively.
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