03/12/11

Red Tilapia Body Colour Genetics and Variations


Recently red tilapia strains are very important for commercial farming in South and East Asia, Caribbean and Latin American countries mainly for their high productivity, tolerant to medium or high salinity and especially for consumer's preference due to their excellent body colour. Commercially available red tilapia strains are mostly hybrids and products of inter specific cross breeding involving as many as four different tilapia species in which Oreochromis mossambicus and O. niloticus are predominant. 

In the early 90's we thoroughly studied body colour inheritance and genetics of Egyptian and Thai red strains in the Institute of Aquaculture, Stirling University, Scotland. It has been experimentally proved that the existing stocks of the Egyptian and Thai red strains are a mixture of both heterozygous and homozygous genes but mostly are heterozygote that do not bred true (not able to produce all red colour progeny). Another problem associated with the appearance of varying proportions of blotched types (presence of ugly black spots over the skin), which are not valuable to the consumers as the pure red individuals.

Subsequently, in 2005 onwards we also studied the body colour genetics of Malaysian red tilapia strain in Bangladesh Fisheries Research Institute, Mymensingh. In this strain we observed majority of the population having homozygous red gene, the homozygote breeders can breed true (able to produce all red colour progeny) all along the following generations. So, probably, the Malaysian tilapia farmers did not face serious problem of availability of varying proportion of blotched type fish in their commercial farming. Although red strain has promising future but it is not yet very popular species for commercial tilapia farming in Bangladesh.

I wonder, if red tilapia esteemed researchers and farmers can come forward to explain their observations and experiences in these aspects who are working with other commercially important red tilapia strains viz. Florida, Jamaican, Taiwanese and Philippines red strains.


Dr. M. G. Hussain