CRSP Research Report 04-200
Effect of Oxygen Saturation in Water on
Reproductive Performances of Pacu Piaractus brachypomus
Konrad Dabrowski and Jacques Rinchard
School of Natural Resources
The Ohio State University
Columbus, Ohio 43240 USA
Joseph S. Ottobre
Department of Animal Science
The Ohio State University
Columbus, Ohio 43240 USA
Fernando Alcantara and Palmira Padilla
Instituto de Investigaciones de la Amazonia Peruana
Iquitos, Peru
Andrzej Ciereszko
Department of Molecular Andrology
Polish Academy of Sciences
Olsztyn-Kortowo, Poland
Marcos J. De Jesus and Christopher C. Kohler
Fisheries Research Laboratory
Southern Illinois University
Carbondale, Illinois 62901 USA
Broodstock pacu Piaractus brachypomus as well as their eggs during their embryonic development were exposed to either normoxia (5.5-7.5 2/L) or hypoxia (2.04.5 mg O2/L) conditions. The plasma concentrations of 11-ketotestosterone in males and estradiol-17 in females, as well as that of their precursor testosterone (T) were significantly (P < 0.01) higher in fish maintained under normoxic conditions than in fish exposed to hypoxia. After ovulation and spermiation induced by hormonal treatments, the plasma concentrations of T and 17,20 -dihydroxy-4-pregnen-3-one (17,20 P) significantly (P < 0.05) increased in both sexes under both normoxic and hypoxic conditions. The plasma levels of T and 17,20 P achieved
CRSP Research Report 04-199
Gamitana (Colossoma macropomum) and Paco
(Piaractus brachypomus) culture in floating cages in the Peruvian Amazon
Fernando Alcantara B., Carlos Chávez V.,
Luciano Rodriguez C., and S. Tello
Instituto de Investigaciones de la Amazonia Peruana
Programa de Ecosistemas Acuáticos
Av. Abelardo Quiñónez, Km. 2.5
Iquitos, Peru.
Christopher C. Kohler, Susan T. Kohler, and
William Camargo N.
Fisheries and Illinois Aquaculture Center
Southern Illinois University at Carbondale
Carbondale, Illinois 62901, USA
Marco Colace
NGO Terra Nuova
Av. Abelardo Quiñónez, Km. 2.5
Iquitos, Peru
In April 1999, the Institute for Investigations of the Peruvian Amazon (IIAP) located in Iquitos (Loreto region) with the Italian NGO Terra Nuova and Southern Illinois University at Carbondale (SIUC), through the auspices of the PD/A CRSP-USAID program, initiated the Food Security Program for Familiar Productive Units (PROSEAL) between the Iquitos-Nauta Road and the Tigre River (Santa Helena and Huayococha). The goal of this program was to produce fish in ponds and floating cages as a way of providing tools to improve the animal protein intake of the Quichuas indigenous population and other rural poor.
This article is restricted to the experiences gained through a demonstration project on floating cages. Fish culture in cages floating directly in the natural environment in the Peruvian Amazon hat not been reported previously; thus many issues had to be resolved for it to be successful. The two predominant concerns were: 1) the behavior of major predators, such as dolphins (Inia geoffrensis and Sotalia fluviatilis), crocodiles (Caiman sclerops), and pirañas (Serrasalmus nattereri) towards the unprotected floating cages containing large numbers of fish; and 2) the sociological fact that natives of the region possessed a strong traditional hunting and gathering tradition, with fish culture activities being alien to them.
The fishes selected for cage culture were the gamitana
(Colossoma macropomum‹also known as black cachama or tambaqui), and paco (Piaractus brachypomus‹also known as pacú, white cachama, pirapitinga, or morocoto). The two species have the advantage of being well known to the local population, although recent captures have decreased dramatically as a result of excessive fishing pressure on natural stocks by the Iquitos-based commercial fishing fleet. In this article, we report preliminary results obtained from gamitana and paco culture in floating cages in the Tigre River.
This abstract is excerpted from the orginal paper, which was published in World Aquaculture, 34(3): 22-24.