Staff Publications

Staff Publications

  • external user (warningwarning)
  • Log in as
  • language uk
  • About

    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

    We have a manual that explains all the features 

Record number 333843
Title Effects of carbohydrate addition on production in extensive shrimp culture systems
Author(s) Hari, B.; Kurup, B.M.; Varghese, J.T.; Schrama, J.W.; Verdegem, M.C.J.
Source Aquaculture 241 (2004)1-4. - ISSN 0044-8486 - p. 179 - 194.
Department(s) Aquaculture and Fisheries
Publication type Refereed Article in a scientific journal
Publication year 2004
Keyword(s) penaeus-monodon fabricius - aquaculture systems - nitrogen ratio - high-intensity - water-quality - ponds - exchange - carbon - suspension - ingestion
Abstract One indoor and one on-farm trial were conducted to evaluate the effect of control of carbon/ nitrogen ratio (C/N ratio) by addition of carbohydrate to the water column in extensive types of shrimp culture systems. In the indoor experiment, 25% and 40% dietary protein ('P25' and 'P40') with or without carbohydrate source addition ('P25+CH' and 'P40+CH') were compared in fiber reinforced plastic tanks of 1200-1 capacity stocked with 6 Penaeus monodon juveniles (0.357 +/- 0.01 g) m(-2). In the on-farm trial, 25% dietary protein with carbohydrate ('P25+CH') and 40% dietary protein ('P40') were compared in 250-m(2) earthen ponds stocked with 6 post-larvae of P monodon m(-2). Tapioca flour was used as carbohydrate source and applied to the water column followed by the first feeding during the day in both experiments. The addition of carbohydrate significantly (P <0.001) reduced the total ammonia nitrogen (TAN) in the water and sediment in both experiments. It significantly (P <0.05) increased the total heterotrophic bacterial (THB) population both in water column and sediment. In the indoor experiments, lower specific growth rate (SGR) and higher feed conversion ratio (FCR) values were recorded in the 'P25' treatment compared to shrimps in other treatments (P <0.05). Higher shrimp yield was recorded in 'P25+CH' (64.43 g m(-2)) when compared to 'P40' (44.79 g m(-2)) (p <0.001) in the on-farm trial. The FCR value was lower (P <0.05) in the 'P25+CH' treatment than in the 'P40' treatment. The nitrogen retention (%) and protein efficiency ratio (PER) were higher (P <0.001) in the 'P25+CH' treatment when compared to other treatments in both experiments. Survival of the shrimps was not affected by treatment (P > 0.05). In the on-farm trial the benefit cost ratio was higher in 'P25+CH' treatment than 'P40' (1.3 against 0.2) and the profit increased 400% in 'P25+CH' treatment. A 35% reduction of feed cost and 54% increase in the revenue from shrimp was recorded in the 'P25+CH' treatment when compared to the 'P40'. Control of C/N ratio by the addition of a carbohydrate source to the pond water column benefited the extensive shrimp culture practices in three ways (1) increased heterotrophic bacterial growth supplying bacterial protein to augment the shrimp production, (2) reduced demand for supplemental feed protein and subsequent reduction in feed cost and (3) reduced toxic inorganic nitrogen levels in the pond as well as effluents. (C) 2004 Elsevier B.V. All rights reserved.
There are no comments yet. You can post the first one!
Post a comment
Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.