| Autor: |
Carl D. Webster, L. S. Goodgame-Tiu, James H. Tidwell, Louis R. D'Abramo |
| Rok vydání: |
1994 |
| Předmět: |
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| Zdroj: |
Aquaculture. 126:271-281 |
| ISSN: |
0044-8486 |
| DOI: |
10.1016/0044-8486(94)90043-4 |
| Popis: |
The population structure and weight distribution of Macrobrachium rosenbergii raised in monoculture and fed diets containing different protein sources in earthen ponds under coolwater conditions were studied. Prawns weighing 0.5 (±0.3 g) were stocked into nine 0.02-ha ponds at 4/m2 and fed at body-weight-dependent rates for 110 days. At harvest, percentage distribution by number and weight of three male morphotypes (blue claw, orange claw, and small male) and two of the three female morphotypes (berried and open) were not significantly affected by diet. The percent contribution of virgin females by weight was significantly higher in prawns fed a diet containing 15% fish meal than in prawns fed a diet containing 7.5% fish meal. The male female ratio ranged from 2.5 to 5.3 among treatments and averaged 3.0 overall. Combined data collected from all 9 ponds indicate percentage contribution of biomass by small males was low (1.1%) and by orange claw males was high (71.0%). Among harvested prawns, >88% exceeded 30 g and 96% exceeded 20 g wet weight. These results differ markedly from those of previous studies conducted in areas with higher mean water temperatures. Pond water temperatures in this study were apparently high enough to support rapid growth but below that necessary to stimulate reproductive changes within individuals in the population, thereby disrupting the development of a population structure normally encountered in harvested populations. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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