SciELO - Scientific Electronic Library Online

 
vol.48 issue1Variations on maternal-embryonic relationship in two natural and six laboratory made hybrids of Poeciliopsis monacha-lucida (Pisces, Cyprinodontiformes)Effects of natural and anthropogenic environmental changes on riverine fish assemblages: a framework for ecological assessment of rivers author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Brazilian Archives of Biology and Technology

Print version ISSN 1516-8913

Abstract

BACCARIN, Ana Eliza  and  CAMARGO, Antonio Fernando Monteiro. Characterization and evaluation of the impact of feed management on the effluents of Nile tilapia (Oreochromis niloticus) culture. Braz. arch. biol. technol. [online]. 2005, vol.48, n.1, pp. 81-90. ISSN 1516-8913.  http://dx.doi.org/10.1590/S1516-89132005000100012.

The objective of this study was to evaluate the effect of different feed management on the quality of effluent water generated in Nile tilapia (Oreochromis niloticus) culture ponds. Feed was supplied as follows: natural food, and pelleted, extruded or minced ration. The study was conducted during 19 weeks in 12 continuous water exchange ponds of 300 m2 each, with a population of male Nile tilapia juveniles, in a density equal to 1.7 fish m-2. Feeds contained 30% crude protein, 3,000 kcal digestible energy, and were supplied twice a day. Natural food consisted of chicken manure. Temperature, dissolved oxygen, pH, total phosphorus, total nitrogen, chlorophyll a and suspended solids were monitored weekly in the supplying and effluent water. Water residence time was also determined for the ponds. In general, effluent water quality decreased in all treatments.

Keywords : Fish culture; environmental impact; feed management; effluent.

        · abstract in Portuguese     · text in English     · pdf in English