An examination is made of the applications of microcomputers to aquaculture research, considering in particular data storage and processing and also statistical analysis programmes. Reference is made to development projects with the aim of making use of modern, applied research methods to develop aquaculture technologies applicable for developing countries.
A description is given of the technique used at the Gan Shmuel Fish Breeding Center, in Hadera, Israel, for the commercial mass production of sex inversed Oreochromis hybrids using androgen diets.
A historical account is given of the discovery of Tilapia mossambica and its culture in Indonesia and the resulting success in Java of this species in rural development programs. Consequent introduction of this species to the Philippines and development of the tilapia culture industry is described, comparing it with development of the industry in Indonesia.
The results are presented of trials conducted whereby cassava peel and mango seed were fed to Nile tilapia (Oreochromis niloticus ) fingerlings. Findings indicate that these products may successfully be used as part of thediets of tilapia fingerlings, although further studies are required in order to determine the optimum proportions.
Genetic improvement through selective breeding has been used for millennia on crops and livestock, but up until the 1980s, little had been done to utilize this process for farmed fish. In response to the inadequate supply of tilapia seed and the deteriorating performance of the fish in many aquaculture systems in Asia, WorldFish and partners began the Genetic Improvement of Farmed Tilapia (GIFT) project to develop a faster-growing strain of Nile tilapia (Oreochromis niloticus) that was suitable for both small-scale and commercial aquaculture.
Genetic parameters and selection responses were obtained for harvest body weight of blue tilapia (Oreochromis aureus) from data collected over three generations in a selected population. A total of 18 194 records representing 186 sires and 201 dams were used in the analysis. Within generation heritability estimates for harvest body weight ranged from 0.18 to 0.58. When data from more than one generation were included in the analysis, heritability estimates became more stable (0.33–0.40) and it was 0.33 when all data were included in the analysis.
The maintenance of reference populations of Tilapia is discussed, examining genetic considerations to be taken into account to conserve the gene pool to prevent genetic drift and prevent detrimental levels of inbreeding. The importance of knowledge of the proper effective breeding number and its use in management of the reference population is described.
A summary is presented of studies undertaken regarding the salinity tolerance of tilapias. The implications of thefindings to the culture of tilapias in Taiwan are considered.
The production performances of giant freshwater prawn Macrobrachium rosenbergii and Nile tilapia Oreochromis niloticus in C/N-controlled periphyton-based polyculture systems were evaluated in triplicate. The result of this study could be useful in improving the sustainability of freshwater prawn farming in terms of ecological, social and financial benefits.
Production and supply of fish seed-stock are essential for the promotion of aquaculture. Traditional inland aquaculture was based on the collection of seed-stock from rivers and required the sorting and acclimatising of mixed species. Fine meshed nylon net cages ‘hapas’ have been used for this purpose for Chinese carps in China and in Bangladesh and India for Indian major carp for a long time. Hapa nursing of small fry to larger, more predator-resistant fingerlings has been the focus for intensification of aquaculture in North East Thailand and Lao PDR.