Tilapia farmers in the Philippines commonly use supplemental feeds in the production of Nile tilapia. Recent studies have shown that varying the timing of initial feeding may present cost effective alternatives for growout. Timely addition of supplemental feeds for an entire growout cycle can increase profitability.
The idea of delayed feeding is not new, Researchers in Thailand led by Dr. J, Diana found in 1996 that delayed feeding presented some cost-savings without an apparent downside on fish yield. The present experiments show that this approach can work in the Philippines, too. If applied on a large scale, the savings could be considerable.
Seven farms participated in a series of trials to test the idea that varying the timing of supplemental feeding can reduce feed costs.
Ponds were stocked with sex-reversed GIFT strain of Nile tilapia at an initial density of 4 fish per square meter. All ponds were fertilized weekly with inorganic fertilizer at a rate of 28 kg N per hectare and 5.6 kg P per hectare. This rate is equivalent to using 51 kg of Urea (46-0-0) and 28 kg of Ammonium phosphate (16-20-0) per hectare.
Fish were grown in the ponds using a supplemental diet of rice bran and fish meal beginning at either day 45 or day 75. Growout was continued to 150 days, at which time the fish were harvested. Farmers examined the productivity of their commercial production ponds, and also observed survival, uniformity, and other variables that might affect market value. Market data were used to conduct an economic analysis of the alternative feeding strategies.
The early feeding approach did not significantly improve the yield from the experimental ponds, nor were there any apparent benefits to the fish in terms of uniformity or health. The added costs of early feeding were never recovered, so it would appear that every young tilapia do just fine feeding on naturally-occuring pond organisms during the earlier stages of growout. Our results suggests that starting supplemental feeding later can save on production costs and reduce labor without compromising crop production or quality.
Since during the early stages of the growout, the fish are dependent on natural food, we would like to emphasize the importance of pond fertilization to promote the growth of plankton. The ponds should be fertilized on a regular basis using inorganic fertilizers.
The start of feeding on day 45 vs day 75 had no effect on the gross production of tilapia, despite the fact that early feeding used up more feeds and consequently higher feed cost by 30%.
Using This Strategy on Your Farm
It is possible that reducing feed costs may help increase your farm’s profitability, if you are feeding more than necessary for optimal production. Contact FAC/CLSU for more information or a free technical consultation.
Participants in this study included volunteer farmers in Nueva Ecija, who worked in cooperation with investigators and scientific staff from Central Luzon State University-Freshwater Aquaculture Center and Florida International University-Marine Biology Program.
For more information, contact:
Dr. Remedios B. Bolivar
Freshwater Aquaculture Center
Central Luzon State University
Science City of Munoz, Nueva Ecija
Phone: (044) 456-0608/5279
Email: [email protected]