Mesocosm hatcheries using semi-intensive culture methodologies are characterized by large tanks （40 m3） for fish larvae production at low densities （2-8 larvae/L）, with live prey production within the tank supplem...Mesocosm hatcheries using semi-intensive culture methodologies are characterized by large tanks （40 m3） for fish larvae production at low densities （2-8 larvae/L）, with live prey production within the tank supplemented by exogenous sources of feed. Due to the high biological quality of larvae produced and low level of technological input, these methodologies are regarded as an interesting option to meet the increasing fry demand from the aquaculture industry. This study aimed to describe the experience at Centro de Maricultura da Calheta, Madeira Island, Portugal, with the establishment of a mesocosm hatchery for the production of marine fish larvae. Production trials were initiated with gilthead seabream Sparus aurata. This larval species presented faster growth in total body length （TL） per day （TL = 3.7516e~ ~293day, R2 = 0.9404）, higher survival rate （SR = 31.9%） and comparable swimbladder inflation rates （SB = 90%） to those of larvae reared with intensive methodologies. High larval performance was obtained with two candidate species for aquaculture： the red porgy Pagruspagrus （TL = 3.212e~~39day, R2 = 0.995; SR = 15.3%; SB = 95.7%） and the white seabream Diplodus sargus （TL = 3.6355e~~413day, R2= 0.9824; SR = 25%; SB --- 100%）. Testing ofa 110 m3 mesocosm rearing tank with white seabream larvae revealed limitations associated to larger tanks namely, the amount and quality of live feed required daily. First trials with striped jack （Pseudocararoc dentex） larvae resulted in low larval survival （0.04%）, but the use of a white tank avoided culture management constraints related to positive phototropism. The present results suggest that a mesocosm using semi-intensive methodologies may contribute to species diversification and consequently, to the sustainable development of aquaculture.展开更多
文摘使用毒饵是有效控制红火蚁发生和危害的重要方法之一.研究明确了不同剂量0.045％茚虫威饵剂处理对不同活蚁巢密度红火蚁的防治效果,建立了4个活蚁巢密度、饵剂剂量和防治效果之间的关系方程,获得了防治红火蚁的0.045％茚虫威饵剂的理论使用剂量：单个蚁巢处理饵剂3～6 g、100 m^2面积撒施25～30 g.
文摘Mesocosm hatcheries using semi-intensive culture methodologies are characterized by large tanks （40 m3） for fish larvae production at low densities （2-8 larvae/L）, with live prey production within the tank supplemented by exogenous sources of feed. Due to the high biological quality of larvae produced and low level of technological input, these methodologies are regarded as an interesting option to meet the increasing fry demand from the aquaculture industry. This study aimed to describe the experience at Centro de Maricultura da Calheta, Madeira Island, Portugal, with the establishment of a mesocosm hatchery for the production of marine fish larvae. Production trials were initiated with gilthead seabream Sparus aurata. This larval species presented faster growth in total body length （TL） per day （TL = 3.7516e~ ~293day, R2 = 0.9404）, higher survival rate （SR = 31.9%） and comparable swimbladder inflation rates （SB = 90%） to those of larvae reared with intensive methodologies. High larval performance was obtained with two candidate species for aquaculture： the red porgy Pagruspagrus （TL = 3.212e~~39day, R2 = 0.995; SR = 15.3%; SB = 95.7%） and the white seabream Diplodus sargus （TL = 3.6355e~~413day, R2= 0.9824; SR = 25%; SB --- 100%）. Testing ofa 110 m3 mesocosm rearing tank with white seabream larvae revealed limitations associated to larger tanks namely, the amount and quality of live feed required daily. First trials with striped jack （Pseudocararoc dentex） larvae resulted in low larval survival （0.04%）, but the use of a white tank avoided culture management constraints related to positive phototropism. The present results suggest that a mesocosm using semi-intensive methodologies may contribute to species diversification and consequently, to the sustainable development of aquaculture.
