40 Developments References Bagarinao, T. U. 1991. Biology of milkfish (Chanos chanos Forsskal). Tigbauan, Iloilo, Philippines: SEAFDEC Aquaculture Department.https://repository.seafdec.org.ph/bitstream/ handle/10862/650/bagarinao1991-biology-of-milkfish. pdf?sequence=1&isAllowed=y Crim, L. W. 1985. Methods for acute and chronic hormone administration in fish.” Reproduction and culture of milkfish: 1-13. Emata, A. C. & Marte, C. L. 1994. Natural spawning, egg and fry production of milkfish Chanos chanos (Forsskal), broodstock reared in concrete tanks. Journal of Applied Ichthyology, 10 (1), 10-16. Emata, A. C. 1993. Hormonal, environmental, and dietary manipulation of milkfish broodstock to enhance egg production. In Towards More Effective Utilization of Resources for Sustained Development. Proceedings of the First IFS-NRCP SeminarWorkshop, 26-29 April 1993, Makati, Metro Manila, Philippines (pp. 146-153). Stockholm, Sweden: International Foundation for Water heaters installed near the sand filter tank Science. Kumagai, S. 1984. The ecological aspects of milkfish fry occurrence, particularly in the Philippines, in: ‘Advances in milkfish biology and culture: Proceedings of the Second International Milkfish Aquaculture Conference, 4-8 October 1983, Iloilo City, Philippines (pp. 53-68). Aquaculture Department, Southeast Asian Fisheries Development Center. Lee, C. S., Weber, G. M. & Tamaru, C. S. 1986. Effect of orally administered 17α-methyltestosterone on spermatogenesis in immature milkfish, Chanos chanos Forsskal. Journal of Fish Biology, 29 (5), 567-572. Lin, L. T. 1984. Studies on the induced breeding of milkfish (Chanos chanos Forsskal) reared in ponds. China Fisheries, 378, 3-29. Marte, C. L. 1988. Broodstock management and seed production of milkfish. In J. V. Juario & L. V. Benitez (Eds.), Perspectives in Aquaculture Development in Southeast Left, sand filter tank and water supply canal; right: Water outlet canal going to the broodstock tank and Asia and Japan: Contributions of the SEAFDEC Aquaculture right,Left, sand filter tank and water supply canal; right: Water outlet canal going to the broodstock tank and right, Department. Proceedings of the Seminar on Aquaculture Development in Southeast Asia, 8-12 September 1987, Iloilo Milkfish fry City, Philippines. (pp. 169-194). Tigbauan, Iloilo, Philippines: SEAFDEC, Aquaculture Department. https://repository.seafdec. org.ph/bitstream/handle/10862/145/adsea87p169-194. pdf?sequence=1&isAllowed=y Romana-Eguia, M. R. R., Santos, B. S., Ikeda, M., Basiao, Z. U.& Kijima, A. 2018. Genetic assessment of milkfish (Chanos chanos Forsskal) stocks based on novel short tandem repeats for marker-aided broodstock management. Aquaculture Research, Spawning success with higher water temperature 49 (4), 1557-1568. Wainwright, T. 1982. Milkfish fry seasonality on Tarawa, Kiribati, Figure 4 shows the monthly production of good eggs and the hatched normal larvae from January 2018 to February 2020. Spawning of milkfish in tanks occurs from March to October and ceases from its relationship to fry seasons elsewhere, and to sea surface November to February. This observation is synonymous to the previous observation of milkfish temperatures (SST). Aquaculture, 26 (3-4), 265-271. broodstock that naturally spawns during increased water temperature in the environment. With the Winans, G. A. 1980. Geographic variation in the milkfish, Chanos installation of water heaters in the tanks, spawning occurred from December 2020 to February 2021. chanos. I. Biochemical evidence. Evolution, 558-574. The result of the experiment is encouraging but it, however, needs a longer duration and observation Yap, W. G., Villaluz, A. C., Soriano, M. G. G., Santos, M. N. such as for a period of four years. The longer experiment aims to establish the effect of water 2007. Milkfish production and processing technologies in the temperature inLAY-OUT milkfish spawning efficiency, fecundity, fertilisation rate and larval abnormality rates. PLAN ISOMETRIC Water temperature manipulation in tanks of milkfish broodstock allows the fish to spawn during cold Philippines. months or off-season. Along with the expansionof of hatcheries, improvement of milkfish broodstock, this Figure 3. Schematic diagram the filter tank, water heater setup technology will further increase the production of milkfish in the Philippines and reduce the dependence water canal and (right) the location of 15 water heaters. ofand milkfish fry imports. 40.00
Production in millions
35.003. Schematic diagram of the filter tank, water heater set-up and water canal and (right) filter tank, Figure Figurewater 3. Schematic diagram of the filter tank, water heater set-up and water canal and (right) filter tank, 30.00heater set-up and water canal.
water heater set-up and water canal. 25.00 20.00 15.00 10.00
6
5.00
Dan D. Baliao is Chief, Aquaculture Department, Southeast Asian Fisheries Development Center
6
Roger Edward P. Mamauag, PhD, is Head Technology Verification and Extension Division
0.00
Month/Year Eggs
Leobert D. de la Pena, PhD, is Head, Research Division
Larvae
Figure 4. Monthly production of milkfish eggs and larvae from January 2018 to March 2021. Figure 4.b Monthly production of milkfish eggs and larvae
January 2018 to March 2021.
from
-endDan D. Baliao is Chief, Aquaculture Department, Southeast Asian Fisheries Development Center.
Roger Edward P. Mamauag, PhD,AQUA is Head Technology and Extension Division January/February 2022 CultureVerification Asia Pacific Leobert D. de la Pena, PhD, is Head, Research Division.
All authors are with SEAFDEC/AQD, Tigbauan, Iloilo, Philippines
