Analysis of RAPD loci in Indian mackerel (Rastrelliger kanagurta), as generated by the arbitrary primer OPA 07 (GAAACGGGTG), revealed a maximum within-region genetic variability for samples from the east coast of India. Dendograms did not show clear centre-specific clusters. Restricted intermixing among the individuals between the east and west coasts in suggested.
Advocates of transgenesis consider it an effective means of improving the productivity of aquatic animals. Opponents see it as a threat to both the environment and human health. This is a challenging area because important traits in fish are complex and controlled by multiple genes. Nevertheless, some transgenic lines of "high-growth" tilapia, salmon and carp are nearing the stage at which they could be considered for commercial production.
This proceedings include papers present at the workshop held from 5 to 9th Nov 2007 in Accra, Ghana. The areas cover 1)the present state of the catfish industry in Africa 2)Catfish reproductive management and grow out 3)Catfish nutrition and feeds 4)The application of genetic principles to catfish genetic improvement programs 5)Recommendations on how to best approach the issue of genetic improvement programs for catfish.
Researchers in Malawi are screening and testing indigenous fish species for use in aquaculture and water resources management, using methodologies developed by ICLARM. This article explains the process.
Biologists have long employed morphometry as a tool in identification, grouping of populations and stock identification of fish. For tilapias, studies have been made on the variability of morphomeric characters in Egyptian species (Libosvarsky and Bishara 1986). Truss morphometrics, where the body shape is divided into a series of 'cells' each of which contains information on the shape and size of the fish, were used by Brzeski and Doyle (1988) for Oreochromis mossambicuslurolepis hornorum sex differentiation.
A selective breeding study for live weight based on a fully pedigreed population of GIFT (Genetically Improved Farmed Tilapia) strain was carried out at the Aquaculture Extension Centre, Department of Fisheries, Jitra, Kedah. Progeny were generated in three spawning seasons, 2002, 2003 and 2004. Two lines were created from the 2002 progeny, based on high breeding values (selection line) and for average breeding values (control line).