TILAPIA has become the mainstay of many small-scale aquaculture projects of poor fish farmers in the developing world. "The fish is cultured in more than 70 countries," says Dr. Rafael D. Guerrero III, a national scientist and former executive director of the Philippine Council for Aquatic and Marine Research and Development (PCAMRD).
Fishery experts have dubbed tilapia as "aquatic chicken" because it possesses many positive attributes that suit the fish for a varied range of aquaculture systems. For one, tilapia tolerates a wide range of environmental conditions and is highly resistant to diseases and parasitic infections.
Other good traits of tilapia include excellent growth rates on a low-protein diet, ready breeding in captivity and ease of handling; and, more importantly, wide acceptance as food fish.
"Tilapia has become a very important fish in the world, especially in Asia and Africa," said Dr. Guerrero, who holds a doctorate degree in fisheries management from Auburn University in the United States. "Where you have a problem of protein deficiency, where there is hunger and malnutrition, people depend on rice and cultured fish like tilapia."
With burgeoning populations and less space available for production, the search for a super strain of tilapia continues. In the Philippines, there are four species raised in the country: Oreochromis niloticus, O. mossambicus, O. aureus, and Tilapia zillii.
"Tilapia culture in the Philippines started in the 1950s with the introduction of Mozambique tilapia, a small, black species that was not accepted in the market," Dr. Guerrero recalls. "It was touted as a miracle fish. But there were difficult problems in its management, including overpopulation."
The fish is a prolific breeder that multiplies rapidly. Crowded surroundings stunt its growth. "People criticized the small size of the fish," he said, "and it was sold at very low prices."
It was not until the Nile tilapia was introduced in the country that Filipinos started to like the fish. "The Nile tilapia became popular because of its rapid growth, large size and high yield potential," notes a PCAMRD briefing paper. "Like other tilapias, this species is resistant to parasites and diseases, resistant to overcrowding and has the ability to survive low oxygen levels. They also grow in both natural and artificial fish foods, and utilize manure well. They are excellent table food fish with white firm flesh and no intramuscular bones."
The Nile tilapia was so popular that it became the second most important farmed aquaculture species, after milk fish. But after some initial success and popularity, it was inbred with other species and yields declined.
A ten-year multi-national effort for genetic improvement led to the development of the hugely successful GIFT (Genetically Improved Farmed Tilapia) strain.
Since then, several different strains of Nile tilapia have now been developed within the Philippines and overseas. The Bureau of Freshwater and Aquatic Resources (BFAR) has developed the Genetically Enhanced Tilapia-Excellent (GET-EXEL) strain, and the Freshwater Aquaculture Center of Central Luzon State University (FAC/CLSU) has bred the FaST strain. In Norway, a private company Genomar markets the fish under the name GenoMar Supreme Tilapia (GST).
The GIFT strain has been undergoing 13 generations of selection—five generations in the Philippines and 8 generations in Malaysia. Although the strains account for around 70% of total tilapia production in the Philippines, and the variety of strains offers farmers more variety to choose from, little analysis has been carried to compare the benefits of these strains.
So, a project entitled “Evaluation of Nile Tilapia Strains for Aquaculture in the Philippines” is currently being done by Kuala Lumpur-based WorldFish in partnership with three institutions: the National Freshwater Fisheries Technology Center of BFAR, FAC/CLSU and Feedmix Specialist II. The Bureau of Agricultural Research funds the project.
The ultimate aim of the current study is to identify superior strains of Nile tilapia for aquaculture in the Philippines. Dr. Tereso Abella, FAC-CLSU’s director and technical consultant from WorldFish, says that identifying the best performing strain in the country will have vast social and economic benefits.
"The goal of the project is to develop and make available the best strain of Nile tilapia for the industry,” he explains. “We want the product of this research project widely disseminated to both large and small-scale tilapia farmers but higher priority will be given to small scale tilapia farmers to improve their production, and the quality of their lives.”
This will help increase aquaculture productivity, generating greater income for small-scale fish farmers, improving their living standards, and helping to increase the availability of Nile Tilapia for poor consumers. It is also expected to contribute to gender equality through the creation of employment opportunities for women.