Nutrition of Colossoma macropomum and Piaractus brachypomus
Tenth Work Plan, Feeds and Fertilizers Research 1 (10FFR1)
Final Report
Christopher C. Kohler
Fisheries and Illinois Aquaculture Center
Southern Illinois University at Carbondale
Carbondale, Illinois, USA
Susan T. Kohler
Economic and Regional Development Office
Southern Illinois University at Carbondale
Carbondale, Illinois, USA
Fernando Alc‡ntara Bocanegra
Instituto de Investigaciones de la Amazonia Peruana
Iquitos, Peru
William M. Camargo
Fisheries and Illinois Aquaculture Center
Southern Illinois University at Carbondale
Carbondale, Illinois, USA
Salvador Tello
Instituto de Investigaciones de la Amazonia Peruana
Iquitos, Peru
Abstract
Research studies provided considerable information related to the nutrition, feeding, and general culture of targeted Amazonian fish species. Three diets were formulated with crude protein (CP) levels at 22, 27, and 32% using the same ingredients as diets in the Ninth Work Plan to feed Piaractus brachypomus. Nine ponds (3 treatments with 3 replicates) were stocked at a rate of 8,000 25-g fingerlings ha-1. Pond liming, fertilizing, conditioning, feed ration adjustment, and water quality monitoring were accomplished as in previous work plans. Piaractus brachypomus grew similarly with all three diets over a six-month trial, though condition factor was highest among fish fed the 32% CP diet. Based on these results, the standard 28% CP diet currently being employed by the Instituto de Investigaciones de la Amazonia Peruana appears to be a suitable diet for grow-out, but diets lower in CP levels (perhaps 25%) should be considered to further reduce costs. We designed two diets that our Peruvian PhD student will test in the Eleventh Work Plan for acceptability and digestibility. From June to March 2003, a study was conducted as part of the same Peruvian studentÕs dissertation to assess the role of P. brachypomus and Colossoma macropomum in seed dispersal throughout the flooded forest. Three C. macropomum and three P. brachypomus for each of three weight-groups
(1, 3, and ³ 5kg) were placed in randomly assigned cages (6 m3) floating in ponds. Fish were starved for two days to ensure they had released their gastric contents before being fed fruits and seeds (one of each at a time) until satiation. After verifying fish seed consumption, fish were placed into individual tile-lined raceways to collect seedsÑboth whole and brokenÑin the feces. Digested and undigested seeds from the same tree (control) were sowed into sterilized humus to determine their viability and germination rate. Seeds of some of the different fruits ingested by the fish germinated at rates as good or better than did controls.
Introduction
In South America, eight countries have USAID-presence status (Bolivia, Brazil, Colombia, Ecuador, Guyana, Para
guay, Peru, and Venezuela). Excluding Paraguay, these countries are linked by major river systems, particularly the drainages comprising the Amazon and Orinoco Rivers,
