Budidaya Burayak ikan laut di Jepang

MARINE FISH LARVAL CULTURE IN JAPAN. Presently the techniques of marine fish larval culture has well developed in several countries such as in Japan. In Japan, this effort has been commonly practiced in large scale. Therefore, the seed production of the culture has fulfilled the seed demand of fish culture itself, and even every year millions of seeds are released into the sea to enchance natural fishery. This paper describes the basic techniques of marine fish larval culture in general and larval culture of Pagrus major is presented as an example of mass culture of marine fish larvae. The basic techniques of fish larval culture may be broadly divided into two parts. The first part is the collecting and hatching of eggs, and the second part is the rearing of larvae. The egg collecting should be done carefully. Only good eggs are choosen and should be avoided from physical damage. The eggs have to be incubated in suitable temperature and salinity, and should be sufficiently aerated. There are several important things that should be paid attention in rearing of larvae i.e. the food should be sufficiently provided and suitable for various developmental stage of larvae, and water quality should be maintained in good condition. The organisms which are commonly used as live food for fish larvae are rotifer Brachionus plicatilis, copepod Tigriopus japonicus and brine shrimp Artemia salina. Pellet (artificial food) could be given as additional food After metamorphosis to juvenile stage, they could be fed with minced fish, shellfish and shrimp particularly for the carnivorous or omnivorous fishes. Rearing water should be maintained at suitable temperature and salinity with sufficient dissolved oxygen concentration, and be avoided from many kinds of pollutants and diseases.