Occurrence of milkfish eggs in the adjacent waters of Panay Island, Philippines
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Location of spawning grounds of milkfish is one of the most important steps towards gaining knowledge on the spawning habits of the fish as well as the early life history and nature of its eggs and larvae. The present study is an attempt towards this objective. Surveys were made in selected areas in the sea around the Panay Island and milkfish eggs were collected on several occasions from surface to 20 m depth water by towing with larval nets. The eggs floated in the water in a glass jar. The eggs and newly hatched larvae had the same characteristics as described by Delsman (1929). A comparative study has been made to distinguish milkfish eggs from other more or less similar size pelagic eggs of fishes occurring in the same waters at the same time.
Senta, T., Kumagai, S., & Ver, L. (1976). Occurrence of milkfish eggs in the adjacent waters of Panay Island, Philippines. In Proceedings of the International Milkfish Workshop Conference, May 19-22, 1976, Tigbauan, Iloilo, Philippines (pp. 167-180). Tigbauan, Iloilo, Philippines: Aquaculture Department, Southeast Asian Fisheries Development Center. http://hdl.handle.net/10862/3365
PublisherAquaculture Department, Southeast Asian Fisheries Development Center
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Conference paperTY Wee - In BO Acosta, RM Coloso, EGT de Jesus-Ayson & JD Toledo (Eds.), Sustainable aquaculture development for food security in Southeast Asia towards 2020. Proceedings of the Regional Technical Consultation on Sustainable Aquaculture Development in Southeast Asia Towards 2020, 2011 - Aquaculture Department, Southeast Asian Fisheries Development CenterSingapore is a small island state and its development of commercial aquaculture started only in the early 1970s. The foodfish aquaculture industry currently produces about 4% of the estimated 100,000 mt of fish consumed annually. The main bulk of foodfish production comes from marine coastal farms and some from land-based foodfish farms. The Agri-Food and Veterinary Authority of Singapore (AVA) is the national authority for aquaculture development for Singapore and manages aquaculture farms through the issuance of farm licenses. For marine foodfish farms, the farm licensee has to abide by good farm management guidelines to maintain the farm in good condition and ensure that the farm does not engage in activities that would pollute the farm waters. For land-based farms, there are also guidelines that address infrastructure layout, farming system and water treatment facilities. The latter requires that sedimentation ponds, reservoir ponds/tanks, supply and drainage systems, trade effluent treatment and sampling plant are included in the farm set-up. Aquaculture, as with all other food production practices, is facing challenges for sustainable development. An example of Singapore s contribution to sustainable aquaculture is through the development of technology for consistent and economical mass production of fish seeds under controlled conditions. This approach will alleviate the pressure on nature to provide the seeds for farming and would make available large numbers of quality fish for small and large-scale commercial aquaculture. AVA has established the Marine Aquaculture Centre (MAC) at St. John's Island to address the needs of aquaculture development for Singapore through fish reproduction and seed production technology development as well as large- scale fish farming technology development. At present, the fish reproduction technology research work involves closing the reproductive cycles of key marine food fish species and also fry production at a commercial scale. Closing the reproductive cycles will eliminate the reliance and alleviate the pressure on wild seed stock. Good quality brooders are selected, maintained and bred to produce quality fry, which would indirectly translate to better growth performances and shorter culture period. This, together with good farm management practices, will optimize the usage offish feeds during the culture cycle. AVA is looking into the use of vaccination for fish health management purpose, to reduce the reliance on prophylactic drugs in the future. Antibiotics or chemicals if not administered properly for treatment may have negative consequences. One of them is the presence of drug residues in aquatic products which has food safety and health concerns. Other issues include adverse effects on the environment such as build-up resistance of pathogens. In the past, the focus of attention in aquaculture management had been on increasing yield by culture practices, with a view to short-term economic viability. With the current rate of depleting marine resources, there is an urgent need to develop aquaculture in a sustainable way. Current efforts and future developments such as implementation of surveillance programmes, personnel training, fish nutrition and feeding, fish health, the establishment of good aquaculture practices, monitoring of the fish farming environment seawater re-use and information sharing will facilitate working towards the development of sustainable aquaculture in Singapore.
Conference paperK Fukusho - In CL Marte, GF Quinitio & AC Emata (Eds.), Proceedings of the Seminar-Workshop on Breeding and Seed Production of Cultured Finfishes in the Philippines, Tigbauan, Iloilo, Philippines, 4-5 May 1993, 1996 - Aquaculture Department, Southeast Asian Fisheries Development CenterWith economic development and increased demand for high price fish, industrial scale marine finfish culture in Japan was started in 1960-1965 for yellowtail Seriola quinqueradiata. Sustainable supply of wild juvenile and development of floating cage with synthetic fiber net have spurred the culture of nearly 30 species and total production in 1991 is 265 x 103 metric tons (nearly 25% of total aquaculture production). Although salmon ranching had been started in 1888, a national project of ocean ranching was only initiated in 1963 with the present target of 26 species of marine finfish. Ocean ranching aims to increase fisheries resources in coastal sea by stocking hatchery-reared juveniles and preservation of environmental capacity and habitat. Therefore, mass production of marine finfish juveniles is being done for the intensive culture in net cage and for stocking coastal sea in Japan. Nearly 200 million juveniles are produced by ocean ranching centers (14 national, 49 prefectural, 21 city and town, 53 fishermen's association). The number of target fish is about 60 species (excluding salmon and trout). The main species produced are red sea bream, Pagrus major, flounder, Paralichthys olivaceus, puffer, Takifugu rubrapes, rockfish, Sebastes shlegeli, and mud dab, Limanda yokohamae. More than one million juveniles of these species are produced at one hatchery or ocean ranching center per one fry production season. About 70% of total production of juveniles consist of red sea bream and flounder. Red sea bream could be used to introduce mass larval rearing technology in Japan since its mass production is well developed. The focus of the present paper is the present status and short history of the development in larval rearing technology for red sea bream.