Gần đây phát triển nghề nuôi cá biển ở các vùng nước ven biển của Việt Nam đòi hỏi chất lượng giống thả. Do đó, nỗ lực to lớn, được đầu tư Thiết lập nối kết trong sản xuất sản xuất giống cho các loài nuôi Một số phổ biến, như vậy như cá chẽm châu Á (Lates calcarifer), cá mú (Epinephelus spp.) và cá giò (Rachycentron canadum). Trong khi một số lượng đáng kể của giống đã được sản xuất bởi các Hatchery địa phương, cá vẫn còn quá nhỏ để thả nuôi ao, net lồng | MASS PRODUCTION OF QUALITY MARINE FISH FINGERLINGS BY IN-POND FLOATING RACEWAYS Hoang Tung1 Michael Burke2 Huynh Kim Khanh3 1 School of Biotechnology International University Vietnam. Email htung@ 2 Queensland Department of Primary Industries Fisheries Australia 3 Department of Agriculture and Rural Development Khanh Hoa Vietnam INTRODUCTION Recent development of marine fish farming in coastal waters of Vietnam demands more quality fingerlings for stocking. Consequently tremendous effort has been invested in establishing reliable hatchery production for several popularly-cultured species such as the Asian seabass Lates calcarifer groupers Epinephelus spp. and cobia Rachycentron canadum . While a significant number of fingerlings have been produced by the local hatcheries the fish are still too small for stocking in grow-out ponds or net cages. Tank production of large-sized fingerlings is possible but is costly and requires large nursing area. Meanwhile advanced nursing in ponds is often associated with poor survival and very limited management over fish health. To address this problem the CARD VIE062 04 Project adopted the principles of in-pond floating raceway and successfully developed effective methods for grow-out production in Australia and mass production of large-sized marine fish fingerlings with high quality at low costs in Vietnam. Figure 1 Working principles of in-pond floating raceway 1 Floating raceways FRs have been experimented successfully for freshwater fish farming in USA Masser Lazur 1997 Germany Gottschalk et al. 2005 and Australia Burke et al. 2007 . Basically FR is a long narrow tank either self-floating or supported to float in a reservoir pond or sheltered waters. Water is circulated continuously through the raceway by an air-lift system which also helps increase dissolved oxygen level. Thanks to high water exchange rate fish can be stocked as high density up to 70 kg m3. Since the cultured fish are condensed in the raceway .
