Philippines Research

Background
Collaborative work involving the Freshwater Aquaculture Center at Central Luzon State University (FAC/CLSU) and the University of Hawaii (UH) began as part of the Pond Dynamics/Aquaculture CRSP Sixth Work Plan in 1991. Originally started as a relatively small-scale ancillary component of the Thailand project, this collaboration has grown steadily and the scope of work has increased to the degree that FAC/CLSU is now considered to meet all requirements for selection as a CRSP prime site in the Philippines.

In support of this change in the status of FAC/CLSU within the PD/A CRSP program, socioeconomic studies carried out by Molnar et al. (1994) concluded that Central Luzon is receptive to the adoption of new technology and should therefore benefit from a concentration of CRSP activities in the area. Among other observations, it was noted that aquaculture methods and concepts consistent with ideas developed within the CRSP program have been advocated by the Philippine Bureau of Fisheries and Aquatic Resources (BFAR) for many years. CRSP activity, however, has led to a demonstrable increase in attainable yields of pond-grown tilapia.

Research at the CLSU site to date has concentrated on pond fertilization protocols and examination of strain-related differences in growout performance among tilapia. The cumulative experience of CLSU and UH participants has led us to the conclusion that despite improved yields, optimization of the pond fertilization strategy and pond management methods leaves many of the practical problems that limit the intensification of tilapia production in the Northern Philippines unresolved. Studies conducted by the CRSP in Thailand suggest that supplemental feeding of tilapia in fertilized ponds may induce growth advantages over feeding or fertilization alone (Diana et al., 1994a). Our goal for the proposed project is to explore the possibility that low-level feeding or feeding during only part of the grow-out phase may promote production in a cost-effective manner that will be readily acceptable for fish farmers in the Philippines.

Work on genetics of Oreochromis niloticus hybrids is the subject of a continuing effort under the direction of the International Center for Living Aquatic Resource Management (ICLARM) Genetic Improvement of Farmed Tilapia (GIFT) project. This project is also being carried out at CLSU. We will remain closely attuned to this project, assisting to the degree that we can, and integrating their results with our own as our project progresses. The UH/CLSU collaboration has also involved “genetically male tilapia” work conducted at CLSU by the U. Wales/Swansea project.

One specific problem requiring attention is the production of monosex tilapia, which has been problematic at the CLSU hatchery despite apparently adequate training and background knowledge in the technology. Although this is not a primary focus of our research, we will troubleshoot this and other problems that arise at CLSU to the best of our ability.

Research Problem
A variety of farming methods are currently in practice in the Philippines, ranging from family-scale subsistence production to commercial-scale farming. It is generally true that all tilapia produced can be sold, and recently markets for larger tilapia at premium prices have developed. For these reasons, we feel that the major project emphasis should be on a practical component of production at this time, and one which can be integrated into farming that takes place on a range of different scales.

The proposed work aims to contribute to optimized intensification of tilapia farming through a combination of on-farm and on-station development of:

It is has recently become generally profitable to grow tilapia in ponds in central Luzon, to the degree that intensification beyond the traditional fertilization strategy (i.e., use of prepared feeds, increased stocking densities) has begun. A notable difference from the earlier traditional market condition is that there is now a substantial price premium for tilapia of larger sizes (at least 250 to 300 g/fish). Production of this product involves feeding the fish during at least some portions of the production cycle. However, both researchers and farmers are aware that feed costs are high and can compromise profits. At present, practices are variable and the progress of intensification on particular farms may be disorderly and of a trial-and-error character. Technical guidance would smooth and hasten progress toward optimization.

Concurrently, there are and will remain small farms which are unlikely to follow optimal intensification methods, but which may nevertheless benefit from recommendations developed by the PD/A CRSP. The logical progression from the CRSPs development of efficient fertilization protocols is to integrate options of stepwise intensification by way of supplemental feeding, and other management practices. Therefore, pond production of tilapia and other fishes in central Luzon, already one of the Philippines’ most productive inland regions, would benefit from the dissemination of a comprehensive approach to a range of intensity levels, all having a sound theoretical and empirical basis, and all having been demonstrated under local conditions. This has been done, though largely on-station in the case of feeding experiments, by the Thailand CRSP project (Szyper et al., 1995; Table 1).

Objectives
The overall goal of the proposed work is to develop and disseminate improved pond management options for intensified production of tilapia by farmers with different resources and capabilities. Specific objectives are to:

1) Demonstrate, refine, and disseminate efficient supplemental feeding practices for production of tilapia in fertilized ponds, by means of on-farm trials and additional experimentation;
2) Study and standardize a series of incremental stepwise intensification measures which can be used by farmers to the degree that is most appropriate for their particular situation;
3) Perform the Eighth Work Plan Global Experiment as it has been designed by the PD/A CRSP; and
4) Develop an effective administrative presence within the project, for the purpose of coordinating prime-site functions, and to integrate them constructively into regional activities.

Work Plan and Technical Considerations
1) Characterization of the Research Site
The Freshwater Aquaculture Center at Central Luzon State University has already been the subject of general site characterization, including a description of the site layout, climate, water and soil quality parameters (Bowman and Clair, 1996; Egna, 1997).

2) Proposed Collaborative Work
The body of our proposed research directly addresses one of the priority areas for research activities listed in the Request for Proposals—intensification of aquaculture production techniques. The concept of a stepwise program of intensification options was developed in discussions with farmers and host country scientists. In addition, our response to the host country’s request for assistance with problems in the consistency of hatchery production of monosex tilapia will address the first priority, although more as a matter of technical assistance than as a formal program of experimental investigations. We believe the proposed activities present a balance of scientific and technical work that integrates the research interests of the US and Host Country participants, in keeping with point 8 under “Major Programmatic Considerations,” which emphasizes recognition of joint decisionmaking between Lead Institution and Host Country PIs.

The program will begin with on-farm trials aimed at demonstration of practices which increase fish production in fertilized ponds by supplemental feeding with lower feed inputs than are required for complete feeding throughout the entire production cycle. Our working hypothesis is that feeding at less than satiation promotes growth cost-effectively, and can provide a means of incrementally increasing the degree of intensification which will be of practical use to farmers.

The work begins on-farm in order to facilitate adoption of successful practices both within and beyond the collaborating group as rapidly as possible. On-station activity and resources will be invoked to answer questions which may arise in management of the on-farm work or in analysis of the data. Because on-farm trials differ from on-station experimentation in terms of the degree to which variables can be controlled, on-farm trials will be used to detect different outcomes resulting from only two very different levels of a factor, daily ration for example. Should outcomes differ substantially, on-station experiments can then examine the factor at several well-controlled levels in order to determine a response curve. In addition, the on-station pond experimentation will contribute to the development of a standardized set of stepwise intensification measures that can be used for pond production systems. The incorporation of less expensive, locally available materials into feeds will be addressed by a collaborating US-based CRSP component project (U. of Arizona) during the effective dates of our project and presumably during its continuation. We will provide technical support for this project and will integrate its results into our own intensification studies. Also, the CRSP Eighth Work Plan Global Experiment will be carried out, in keeping with the guidelines set forth by the Technical Committee.

The proposed work can begin with on-farm trials because the initial values of trial parameters (ration levels, etc.) can be adapted for local conditions from results obtained by the CRSP Thailand project (Diana et al., 1994a, b, c). Technical exchange with the AIT site is given a high priority for our project, not only because the work that we propose follows similar lines of thought, but also because we feel that cooperation between CLSU and AIT will be important in the emergence of the new prime site and in the eventual fulfillment of its role as a center for regional activities.

The program will progress through similar stages of optimization of feeding practices, detailed below. It is fairly safe to predict that each of the conceptual stages will successfully demonstrate improvement (saving of feed inputs and reduced loading of static and output waters) over constant feeding regimes, but with differences particular to the regional socioeconomic and natural environments.

Because this work is oriented to prompt dissemination, an important part of the activity will be production of a sequence of handout pamphlets and presentation aids (overhead computer screen projection, videotape recordings) matched to each of the anticipated stages of technical progress in on-farm trials. Upon completion of each topic in one or more on-farm trials, a farmers’ workshop session will be arranged to disseminate the results and practical consequences. Farmer collaborators will be given pamphlets based on results of the previous stage for distribution to visitors to their farms. The involvement of an Aquaculture Extension Specialist from UH at the level of Associate Investigator is intended to improve the quality and efficiency of dissemination of results to farmers.

Experimental Design
The on-farm trials will proceed with a common framework:

Number of Farmers: At least 20 farmers will be enlisted for each trial; no more than two comparison groups per trial will be made. Although yield data will be examined for differences between groups, the primary orientation is to demonstrate the efficacy of practices performed by all participants.

Stocking: Ponds will be stocked with sex-reversed Nile tilapia (Oreochromis niloticus) of a single strain for each trial, at an individual weight of 5 to 10 g/fish, and a density of 4 fish/m2. The best available strain will be chosen based on results of current trials. This density is higher than the optimal 2 to 3 fish/m2 used for fertilized, unfed ponds, but lower than the observed optimum of approximately 6 fish/m2 for the Thailand experiments. Density will be adjusted later in the series of trials as described below.

Fertilization: All ponds will be fertilized weekly with urea and 16-20-0 at a rate of 4 kg N/ha/d and an N:P ratio by weight of 5:1, for at least 60 days in each trial. This is done in order to feed the fish from the pond ecosystem as long and as well as possible, testing the input of prepared feed as a supplement.

Sampling: Ponds will be sampled monthly for water quality (water-column integrated samples for analysis of dissolved oxygen, pH, total alkalinity, total ammonia, and soluble reactive phosphorus) to document the nutrient regimes supporting the blooms and which constitute the loading of waters to be discharged upon harvest. Analyses will be done at the FAC laboratory according to standard methods (Boyd, 1979; APHA, 1980). Fish will be sampled monthly for bulk weight and count of at least 25 fish taken without pattern from a seine haul. Ponds will be harvested by seining and complete draining where possible at 120 to 150 days in pond, or at an approximate fish weight of 300 g/fish, a currently desirable “larger” market size.

The sequence of trials will be:
1) Timing of the Onset of Supplemental Feeding
Diana et al. (1994b) showed that initiation of feeding of O. niloticus after 80 days in the pond produced the same yield at the same time as initiation of feeding at 38 days. Later feeding also increased growth rates and yields to the target levels, but with some delay over earlier feeding. This means that fish do not need to be fed immediately upon stocking, but can be supported by the pond ecosystem. For this on-farm trial, two groups of farmers (all able and willing to buy sufficient feed for the trial) will begin feeding the fish at 30 and 60 days-in-pond. Results may indicate that refinement of the optimal feeding time is possible with an on-station trial which examines more than two periods of delay before feeding.

2) Reduction of Rations below Satiation Levels
Diana et al. (1994a) showed that yields of O. niloticus were nearly equal at rations of 100%, 75%, and 50% of experimentally determined satiation levels. In other words, reduced amounts of feed may be offered without sacrificing production, but only if these amounts are carefully determined. For this trial, two groups of farmers will feed ponds twice daily at 100 and 67% of experimentally determined satiation. The determination of satiation requirements will be made once per week by project personnel on each farm, who will mark a container for the farmer’s use with the volume of feed to be offered twice daily for the coming week. Results may indicate that refinement of the optimal ration will be possible following an on-station trial which examines more than two ration levels.

3) Stocking Density and Feeding Regime for Optimal Pond Production
At least 20 farmers will be recruited to participate in a trial which offers a range of input (and likely yield and profit) options, based on a continuum from low feed inputs and densities up to the feeding and stocking parameters representing a fully intensified system. Based on the Thailand results and the design of trials 1 and 2 above, the highest intensity level in this trial would be conducted with initial fertilization before fish stocking at 6 fish/m2, and supplemental feeding at 67% satiation to begin after 60 days in pond. Lower stocking and input options would be arranged either to match the capabilities and willingness of participants or to create a range of input levels artificially. An extension workshop will explain the trial near its beginning; participants and others will be invited to visit participating farms in the company of project personnel during the trial.

4) Workshops and Production of Improved Extension Materials
Each on-farm trial will be analyzed, and a farmers’ workshop prepared based on the results. If on-station experimentation is called for, the workshop will not await its completion, but will proceed, with a target date not later than three months after a trial’s harvest is completed. Extension will be facilitated by production of illustrated pamphlets describing each of the stages discussed above. The fertilization and feed leaflets used by the AIT projects in Northeast Thailand will serve as a model for development of materials here. These will be refined by circulation of drafts to other organizations (Bureau of Fisheries and Aquatic Resources, BFAR) involved in aquaculture extension functions, and by reviews of draft documents by selected recipients to determine the clarity, effectiveness, and appropriate technical level of the information. Participating farmers will be given multiple copies of the pamphlets appropriate to each completed trial, for distribution to their own neighbors and visitors. The high level of literacy in the Philippines makes distribution of printed materials an effective nationwide mechanism for dissemination.

Expected Outcomes
At the end of the first two-year period, the first two on-farm trials will have been completed, and the collaborators arranged for the third. One or two of the post-trial workshops will have been held. Accordingly, approximately 100 farmers will have had direct contact with project personnel and results, with secondary contacts being much more numerous. Intensification of pond production of tilapia will have been fostered along more efficient and sustainable pathways than would otherwise have been the case if unguided farmers proceeded from opportunistic motives to overstock and overfeed. Sustainability will further be favored by availability of the product of the projected U. of Arizona project, namely, a low-cost supplemental feed based on locally available materials. The extension materials will be available for at least the first trial and workshop, with those for the second near at hand. Project personnel and others will have learned how to use the appropriate tools and materials, which will likely be shared widely at FAC, and will have this project’s products as examples.

Beneficiaries
The primary beneficiaries will be the fish producers and consumers of central Luzon, with much wider effect including other regions of the Philippines and Southeast Asia. Yields and parameters, in differing from those obtained on-station in Thailand, will illustrate differences and ranges of outcomes to be expected elsewhere, for example in AITs target area in Vietnam, Laos, and Cambodia.

Other beneficiaries will include other faculty and staff of CLSU, staff of BFAR and other government agencies, and the clientele (students, advisees) of all. CRSP researchers will benefit from the comparisons noted above, and be better able to design and predict outcomes of work in other locations.

Finally, this work has direct applicability to the US tilapia industry because feeds are a major input cost at all levels of system intensification, and all information about the response of fish growth to different feeding practices is valuable when systems are analyzed or designed anew.

Schedule
The first year’s work will consist of establishment of the project team, refurbishment of facilities and equipment stocks as necessary, coordination of start-up for collaborating projects, conduct of the first on-farm trial, analysis of its results and preparation of workshop and distribution materials, conduct and evaluation of the first workshop, and initiation of the Eighth Work Plan Global Experiment*. Thereafter, on-station work which may be called for by the results of the on-farm trial will be performed, and at the same time the next on-farm trial will be initiated. The approximate pace of the work will be one trial, one workshop, and on-station work as appropriate to the trials and the Global Experiment, each year. This means that the third on-farm trial will probably take place during a projected third-year period.

Timing of the Onset of Supplemental Feeding (9FFR4)

Start of investigation: January to February 1999
End of investigation: May 1999
Final report due: July 1999

Reduction of Rations below Satiation Levels (9FFR3)

Start: September 1999
End: January 2000
Final report due: July 2000

Workshop and Production of Improved Extension Materials (9ADR6)

Production of improved extension materials completed: October 1999
Start of first workshop: December 1999
End of first workshop: December 1999

Start of second workshop: March 2000
End of second workshop: March 2000

Final report due: July 2000

Eighth Work Plan Global Experiment (8FFR1Ph)

Cool season trial start: December 1999
Cool season trial end: March 2000

Warm season trial start: May 1999
Warm season trial end: August 1999

Final report due: July 2000

Regional Emphasis of the Planned Research
We recognize the need for an active commitment to project coordination and integration on local and international levels. The University of Hawaii will provide a large measure of this form of support to the project. The first administrative priority in our plan will be to increase and simplify communications with the CLSU site, which have been unreliable. The FAC campus is currently not connected to telephone services by wire, although such connections are anticipated in the near future. The lack of a hardwired phone link has made communications by fax, phone, and email difficult; it has been a common experience of PD/A CRSP personnel to send a message to CLSU and wonder for several days if it may have been received. We have also had Express Mail disappear without a trace. A major improvement of communications at the outset of our project is essential if we are to accommodate current and future CRSP projects wishing to arrange site visits or requiring soil and water samples, etc.

Our approach will be to install a dedicated project computer at FAC/CLSU with the best available processing ability and communications software, and subscribe to cellular and Internet service providers, so that project participants can communicate electronically on a more frequent basis, any time they wish. We have contacted available Internet servers in Manila, which offer several apparently workable service options. We will evaluate cellular services in order to obtain the fastest possible data transmission rates, and when phone lines reach the FAC/CLSU site, we will be among the first to obtain a connection.

The strategy of project management and regional integration hinges to some extent on the fostering of cooperation between the CLSU prime site and the former prime site at the Asian Institute of Technology in Thailand. Our vision of the role of CLSU is that of a center from which new technology can radiate throughout Southeast Asia, and as a base for the establishment of future USAID initiatives in other countries able to benefit from enhanced aquaculture development, such as Sri Lanka, Bangladesh, and Nepal.

* Though the Philippines Global Experiment is printed as part of this work plan, it was funded under Eighth Work Plan research and is in fact the same Global Experiment conducted at other CRSP research sites under the Eighth Work Plan. (As noted in the Introduction to this volume, the Ninth Work Plan does not call for a Global Experiment as a consequence of funding cuts to the program in the third year of the current 5-year grant.)

References
AIT, 1994. Partners in Development: Promotion of Sustainable Aquaculture. The Asian Institute of Technology, Bangkok, Thailand, 98 pp.

APHA (American Public Health Association), 1980. Standard Methods for the Examination of Water and Wastewater. APHA, Washington, D.C.

Bowman, J. and D. Clair, 1996. Pond Dynamics/Aquaculture Collaborative Research Data Reports, Volume 1, Second Edition, General Reference: PD/A CRSP Site Descriptions. PD/A CRSP, Oregon State University, Corvallis, Oregon, 74 pp.

Boyd, C.E., 1979. Water Quality in Warmwater Fish Ponds. Auburn University Agricultural Experiment Station, Auburn, Alabama.

Diana, J.S., C.K. Lin, and K. Jaiyen, 1994a. Supplemental feeding of tilapia in fertilized ponds. J. World Aquacult. Soc., 25:497-506.

Diana, J.S., C.K. Lin, and Y. Yang, 1994b. Timing of supplemental feeding for tilapia production. In:
H. Egna, J. Bowman, B. Goetze, and N. Weidner (Editors), Twelfth Annual Technical Report, Pond Dynamics/Aquaculture Collaborative Research Support Program. Oregon State University, Corvallis, Oregon, pp. 147-152.

Diana, J.S., C.K. Lin, and Y. Yang, 1994c. Stocking density and supplemental feeding in tropical fish ponds. In: H. Egna, J. Bowman, B. Goetze, and N. Weidner (Editors), Twelfth Annual Technical Report, Pond Dynamics/Aquaculture Collaborative Research Support Program. Oregon State University, Corvallis, Oregon, pp. 153-155.

Egna, H.S., 1997. History of the Pond Dynamics/Aquaculture Collaborative Research Support Program. In: H.S. Egna and C. E. Boyd (Editors), Dynamics of Pond Aquaculture. CRC Press, Boca Raton, FL, pp. 19-52.

Kedtag, A.Q., 1993. Production of Nile tilapia (Oreochromis niloticus L.) in ponds applied with high nutrient inputs. M.S. thesis, Central Luzon State University, 86 pp.

Molnar, J.J., T.R. Hanson, and L.L. Lovshin, 1994. Minding the pond: Feeding, fertilization, and stocking practices for tilapia production in Rwanda, Thailand, the Philippines, and Honduras. In: H. Egna,
J. Bowman, B. Goetze, and N. Weidner (Editors), Twelfth Annual Technical Report, Pond Dynamics/Aquaculture Collaborative Research Support Program. Oregon State University, Corvallis, Oregon, pp. 34-46.

Smida, H., W. Krone, T.S. Rothermel, and M.J. Petit, 1992. A Study of International Fisheries Research. Policy and Research Series No. 19, The World Bank, Washington, D.C.

Szyper, J.P., C.K. Lin, D. Little, S. Setboonsarng, A. Yakupitiyage, P. Edwards, and H. Demaine, 1995. Techniques for efficient and sustainable mass production of tilapia in Thailand. Proceedings of the PACON International Sustainable Aquaculture 95 Symposium, Pacific Congress on Marine Science and Technology, Honolulu, Hawaii.

Stage Number	Fertilizer Inputs	Fertilization (kg/ha/week)	Approximate Fish Yield (kg/ha/year)
1	Phosphorus, inorganic	2 units	800
2	Chicken litter	500 units (dry basis)	5,000
3	Inorganic combination	N: 28 units; P: 7 units	8,000
4	Fertilizer & feed	Stage 3 + pellets @ 50% satiation	22,000