Effect of stocking density on survival and growth of critically endangered mahseer, Tor putitora (Hamilton), in nursery ponds
Effects of stocking densities on the growth, survival and production of mahseer ( Tor putitora) fingerlings were examined in a single-stage nursery-rearing system. The experiment was conducted for 8 weeks in six earthen nursery ponds having an area of 0.012 h each. Four-day-old hatchlings stocked at...
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Published in | Aquaculture Vol. 249; no. 1; pp. 275 - 284 |
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Main Authors | , , , , , |
Format | Journal Article |
Language | English |
Published |
Amsterdam
Elsevier B.V
12.09.2005
Elsevier Science Elsevier Sequoia S.A |
Subjects | |
Online Access | Get full text |
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Summary: | Effects of stocking densities on the growth, survival and production of mahseer (
Tor putitora) fingerlings were examined in a single-stage nursery-rearing system. The experiment was conducted for 8 weeks in six earthen nursery ponds having an area of 0.012 h each. Four-day-old hatchlings stocked at 0.6 million/ha was designated as treatment-1 (T
1), 0.8 million/ha as treatment-2 (T
2) and 1.0 million/ha as treatment-3 (T
3). At stocking, all hatchlings were of same age group with a mean length and weight of 1.18
±
0.04 cm and 0.012
±
0.003 g, respectively. Hatchlings in all the treatments were fed with Saudi Bangla (SABINCO) commercial fish feed viz., nursery (32.06% crude protein) for the first 14 days and starter-I (31.53% crude protein) from days 15 to 56. Physico-chemical parameters (temperature, secchi disc transparency, dissolved oxygen, pH and total alkalinity) and plankton populations (phyto- and zooplankton) were at the optimum level for fish culture. Highest weight gain was observed in T
1 and lowest in T
3. Final length, final weight and survival of fingerlings also followed the same trends as weight gain. Fingerlings in T
1 produced significantly higher specific growth rate than T
3, but not than T
2. Feed conversion ratio was significantly higher in T
1 followed by T
2 and T
3 in that order. Significantly higher number of fingerlings was produced in T
3 than in T
2 and T
1, respectively. Despite this, consistently higher net benefits were obtained from T
1 than from T
3 and T
2. Overall, highest growth, survival and benefits of fingerlings were obtained at a density of 0.6 million hatchling/ha. Hence, of the three stocking densities, 0.6 million hatchling/ha appears to be the most suitable stocking density for rearing of mahseer fingerlings in single-stage nursery system. |
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Bibliography: | http://www.elsevier.com/locate/issn/00448486 ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 |
ISSN: | 0044-8486 1873-5622 |
DOI: | 10.1016/j.aquaculture.2005.04.040 |