To find out if pawpaw (Carica papaya) seeds can induce sterility in male Nile tilapia (Oreochromis niloticus) and to determine if sterility so induced is reversible or otherwise, mature male tilapia of mean weight 40 g were treated for 30 days with a low dose (4.9 g/kg/day) and a high dose (9.8 g/kg/day) of ground pawpaw seeds incorporated into their feed. Fish of similar sizes in the control experiment were fed with feed that did not contain pawpaw seed.
This manual, which focuses on pond and rice field ecosystems, is in two parts. Part 1 provides background information for trainers of farmers on using the theory of participatory action learning (PAL), provides a PAL sessionsheet format and gives recommendations for using PAL sessions. A selection of 14 ponds and 4 rice field fish culture PAL session plans is contained in part 2. This manual includes two types of PAL sessions: those which need facilitation only once, and those which farmers can use repeatedly as a diagnostic tool.
Starting from a small base, aquaculture production in Africa registered annual growth rates equal to or above those in other regions. This expansion was due to significant increases in a few African countries. Increasing demand coupled with rapidly dwindling catches from capture fisheries, the implementation of novel participatory approaches to technology development and transfer, and the emergence of a few successful large-scale tilapia culture operations directed at the export market offer opportunities for further expansion in both the small-scale and large-scale commercial sectors.
Wild (Sanaga River) and domesticated populations of Oreochromis niloticus were compared onfarm and on-station in the Central Province of Cameroon to determine the degree to which genetic deterioration of stocks may have occurred during the process of domestication and subsequent breeding. On-station, average weight at harvest was 284.3 ± 16.2 and 178.1 ± 9.9 g for Sanaga and domesticated populations, respectively. On-station specific growth rate was 0.0660 ± 0.0022 and 0.0555 ± 0.0016 g/day for Sanaga and domesticated populations, respectively.
A narration of the collaborative work between ICLARM fish farming / culture program in Bangladesh with the Bangladesh Fisheries Research Institute on potential use of seasonal ponds as small scale fish ponds. The ponds could be used to increase fish production in Bangladesh up to 80%. The women could manage the fish culture and in the process of doing so, contribute to household income, provide employment and improve family nutrition.
A study was carried out to estimate pond-water availability for fish culture by developing and applying a simulation model that can express water budget for fish ponds based on prevailing climatic and hydrological conditions. The model was applied at selected meteorological stations in the floodplains of the Ganges-Brahmaputra delta in Bangladesh from 1998 to 2002.
Determines and measures the constraints to the adoption of more intensive fertilizer application rates among Philippine milkfish farmers. Hypothesized 56 explanatory variables, categorized into socioeconomic, institutional, physical and biotechnical parameters to explain variations in fertilizer use. Focused on farmers' perceptions of constraints. Data from 447 milkfish farmers in seven provinces and from a previous survey of 324 farmers in seven provinces.
An agreement on the need for concerted international efforts for advancing the science of fish breeding and genetics through networking.
Thai pangas, Pangasius sutchi (Syn. P. hypophthahnus) is one of the important species in aquaculture of Bangladesh. Over the last few years, spectacular development of has been taken place in Thai pangas farming in Mymensingh district. Due to quick profit, peoples are converting their rice field into pangas farm. However, when the expansion of pangas farming is almost in its peak, farmers are facing serious disease problems and mortality in their fish. Therefore, to examine health and disease status of Thai pangas, clinical histopathological and bacteriological techniques were employed.
Alien invasive species may cause as much havoc in water-dependent ecosystems, such as wetlands, lakes and rivers, as they do in terrestrial systems. In the aquatic medium they are more diffi cult to detect and eradicate or even to control and there needs to be special effort to avoid such invasions from both alien species and genotypes. This paper describes some of the pathways and impacts of alien and other invasive species in aquatic situations and suggests that the intentional introduction of any species to a new environment should be preceded by a rigorous risk assessment process.