Text and Photos by Henrylito D. Tacio
Davao City, 1 July 2014. After bangus (milkfish), tilapia is now the second most important fish in the Philippines. These days, tilapia fish cages are a common sight in almost all the major rivers and lakes in the country, including Laguna de Bay, Taal Lake, and Lake Sebu. It is very popular among Filipinos who cooked the fish in different ways, including fried, grilled, sinigang (a sour soup using tamarind, santol, guava or calamansi as a base) and paksiw (similar to sinigang only it uses vinegar).
It’s no wonder why tilapia has replaced galunggong as the poor man’s fish. Tilapia has provided many Filipinos, especially the lower income households, with access to cheap source of animal protein.
Dr. Rafael D. Guerrero III, an Academician of the National Academy of Science and Technology who popularized tilapia raising in the country, said the Philippines is “now one of leading producers of tilapia in the world today.”
This has been confirmed by Agriculture Secretary Proceso Alcala during the Fourth Tilapia Congress last year. “The Philippines,” he said, “has maintained its position among top tilapia producing countries, cornering eight percent of the total world production.”
Last year, the world tilapia production exceeded 4 million metric tons, according to Dr. Guerrero. The Philippines contributed more than 260,000 metric tons. “Tilapia is now second only to the carps as the world's most important farmed fish based on production,” he added.
The popularity of tilapia as a food fish has spread around the world. Aside from the Philippines, the other biggest producers in Asia are: China, Malaysia, Vietnam, Indonesia, Taiwan and Sri Lanka. In South America, the top producers are: Brazil, Costa Rica Ecuador and Peru. The United States is the biggest importer of tilapia while China leads as the biggest exporter.
If the Philippines has to maintain its edge, it has to increase its tilapia production in the coming years. But the industry has to solve some of the problems it currently faces: degradation of quality fingerlings due to inbreeding, insufficient supply of quality tilapia fry in far flung areas, high cost of farm inputs and poor quality feeds, lack of technology transfer initiatives at the grassroots level, and lack of value-added products.
As such, the Department of Science and Technology (DOST) thinks of doing interventions to boost capacity of tilapia production systems and enhance product competitiveness. Through its line agency, Philippine Council for Agriculture, Aquatic, and Natural Resources Research and Development (PCAARRD), it launched Strategic Science and Technology Plans (ISP) for tilapia.
PCAARRD, in its recently released annual report, said the ISP for tilapia aims “to produce better-performing breeds, specifically the red tilapia.” Through this program, a base population within red Nile tilapia family has been established.
“Two generations were produced and grown for selection,” the report said. In addition to red Nile tilapia, seven tilapia breeds were collected and crossbred.
As much as 90% of the tilapia cultured in the country is sex-reversed, Dr. Guerrero reported. “At least 50% of the tilapia produced in the United States, Canada, Israel, the Caribbean and Asia is sex-reversed,” he pointed out.
It was Dr. Guerrero himself who developed the sex reversal tilapia (SRT) technology. For his feat, he was awarded the IBM Science and Technology award by the IBM Philippines.
“Artificial sex reversal is considered the most effective, efficient and economical method for solving the major drawback of growing tilapias to market-size caused by unwanted reproduction,” Dr. Guerrero said.
“With mix-sex (male and female) stocks, the fish matures early and breeds frequently resulting in stunted growth due to overpopulation in ponds,” he added. “By growing all-male tilapia produced through hand-sexing (manual separation of sexes), hybridization (crossbreeding of two appropriate species) or sex reversal, the yield of large-sized tilapias is significantly increased by 30 percent to 50 percent because of the faster-growing males compared to females and the control of reproduction.”
The commercial tilapia sex reversal feed (SR Premix) is available from its exclusive manufacturer and distributor, Aquatic Biosystems. Interested individuals can write the owner at this email: aquabios@yahoo.com.
According to Dr. Guerrero, applying the sex reversal feed method with a success rate of at least 95 percent requires the production of the right age of the fry for treatment, preparation of the hormone feed or its procurement, and the proper application of the treatment.
In its annual report, PCAARRD said some of its researchers are currently doing experiments on using pine pollen as source of phytoandrogen (substance in plants that have similar effects to testosterone in animals) to promote sexual inversion.
Tilapia fry given the pine pollen reportedly showed comparable results to the use of synthetic hormone. “The pine pollen-treated males produced fry within 16 days post stocking, which means that the sex inversed females became functional males,” the report said.
To solve the high cost of feeds for tilapia, PCAARRD likewise conducted some studies on various feeds. Initial data on field trials showed positively that fry easily adapted to the feeds introduced.
According to the report, positive increase in terms of average body weight, length, and width of the fish were observed.
The data also showed that ingredients used in the feed formulations -- cassava meal, camote meal, copra meal, corn meal, rice bran, and golden apple snail -- were sufficient to meet the nutritional requirements of cultured tilapias.
This is good news for Filipinos. After all, fish provides more than half of the protein requirement of almost all Filipinos.