Marsupenaeusjaponicus Bate is one of the most valuable cultured shrimp species in China and outdoor earthen pond farming is the most common method of culturing this organism. The need to increase soil usage efficiency...Marsupenaeusjaponicus Bate is one of the most valuable cultured shrimp species in China and outdoor earthen pond farming is the most common method of culturing this organism. The need to increase soil usage efficiency in aquaculture has been recognized and a great deal of research effort has been directed toward development of super-intensive farming systems. However, current research and development in this field is largely devoted to Litopenaeus vannamei Boone, while to M.japonicus Bate it has been neglected. In this study, a layered fanning system was designed and a 66-day study was conducted in M.japonicus Bate culture. The system comprised bracket and sand layers that divided a shrimp tank filled to a depth of 1.2 m into four water layers. Conventional tank culture （unlayered） was used as a control. The results show that survival rate, feed conversion efficiency and production of M.japonicus Bate in the layered farming system were 68%, 18%, and 0.59 kg/m^2, respectively, all of which are significantly higher than in the unlayered fanning system （P〈0.01）. These findings confirmed the possibility of using a layered system to culture M. japonicus Bate.展开更多
Hybrid tilapia weighing 7.71 g were reared in seawater at 24.0-29.0℃ for 8 weeks. The controls were fed to satiation twice a day throughout the experiment, whereas treatment groups were fed at 0.5%, 1.5% or 3.0% body...Hybrid tilapia weighing 7.71 g were reared in seawater at 24.0-29.0℃ for 8 weeks. The controls were fed to satiation twice a day throughout the experiment, whereas treatment groups were fed at 0.5%, 1.5% or 3.0% body weight per day for 4 weeks, and then to satiation for the remainder of the experiment. During the first 4-week period, there was a curvilinear relationship between growth rate and ration size. Fish fed 0.5% and 1.5% rations displayed compensatory growth response of 2 weeks duration during realimentation. The weight-adjusted growth rate of fish fed at 3% ration was not significantly different from that of the controls by the end of the experiment, when none of the treatment groups had caught up in body weight with the controls. Hyperphagia was observed for the first 2 weeks of realimenatation in fish previously fed at 3% ration, but persisted for the whole realimentation period in groups previously fed at 0.5% and 1.5% rations. None of the feed restricted groups showed improved digestibility, feed efficiency, or protein and energy retention efficiency.展开更多
Experiment on phosphorus budget of redeye mullet (Liza haematocheila T. & S.) was con- ducted at water temperature 21℃ and salinity 33. The results showed that the growth phosphorus (phosphorus that allocated int...Experiment on phosphorus budget of redeye mullet (Liza haematocheila T. & S.) was con- ducted at water temperature 21℃ and salinity 33. The results showed that the growth phosphorus (phosphorus that allocated into growth, GP) increased from –30.84% to 15.83% by feeding on graded amount of diets (starvation, 1%, 2%, 3%, 4% body weight and satiation). The GP linearly increased with feeding levels (FL) as GP (mg) =–0.785 + 0.604 FL, and at satiation the relationship between GP and body weight (BW) was GP (mg) = 1.5991 BW 0.768 5. In the budget, IP (intake phosphorus) = GP + FP (faecal phosphorus) + EP (excretion phosphorus). FP showed an irregular tendency with different feeding levels, and EP decreased with increasing feeding levels but rebound at satiation. The P budget at satiation was 100IP = 15.84 GP + 64.62 FP + 19.55 EP.展开更多
The seaweed Sargassum hemiphyllum is widely distributed throughout the coastal waters of Asia and has high commercial value. In recent years, its natural biomass has declined due to over-exploitation and environmental...The seaweed Sargassum hemiphyllum is widely distributed throughout the coastal waters of Asia and has high commercial value. In recent years, its natural biomass has declined due to over-exploitation and environmental pollution. To seek for a feasible way to culture this seaweed efficiently, we designed a simple long-line system in a shrimp pond for the culture during winter, and the growth and nutritional composition of the seaweed were examined. Results show that the cul^re system was durable and flexible allowing S. hemiphyllum to grow vertically offthe muddy bottom of the pond. Although the length of pond- cultured S. hemiphyllum was inhibited by water depth, the weight-specific growth rate （（1.65±0.17）%/d） was nearly three times higher than that of wild plants （（0.62±0.19）%/d）. The crude protein （6.92%±0.88%） and ash content （21.52%±0.07%） of the pond-cultured seaweed were significantly lower than those of the wild plants （9.38%±-0.43% and 26.93%±0.07%, respectively）; however, crude fat （1.01%±0.04%） was significantly higher than that of the wild plants （0.87%±0.02%）. In addition, the nutritional composition of both pond-cultured and wild S. hemiphyllum was comparable to or even higher than those of other common seaweeds being used as food and/or aquaculture fodder. Future studies shall be focused on the impact of environmental parameters on its growth and nutritional composition.展开更多
This study was designed to compare the effect of two exchange rates （ERs; 0.5 m^3 feed/kg and 1.5 m^3 feed/kg） in re-circulating aquaculture systems （RAS） on water quality and fish growth profiles on fish stocks ...This study was designed to compare the effect of two exchange rates （ERs; 0.5 m^3 feed/kg and 1.5 m^3 feed/kg） in re-circulating aquaculture systems （RAS） on water quality and fish growth profiles on fish stocks （200 indiv/m^3 of 251.4 g e 20.67 g） of gilthead bream, Sparus aurata. Water quality, fish growth, specific growth rate （SGR） and feed conversion ratio under the two ERs were examined for a period of six months. Inorganic nutrient in RAS, temperature, dissolved oxygen and pH were measured daily. Feeding regime effect was also determined on the fish quality and organoleptic characteristics and thus opts to energy optimization of the system. The fish reared under the 1.5 m^3 feed/kg ER demonstrate enhanced growth, the daily SGR and the conversion ratio. Sensory test analysis revealed differences in the organoleptic characteristics between the two experimental fish stocks with considerably high acceptance scores for fish reared at high ER. Nutrient concentrations： ammonia, nitrate, nitrite and phosphate were lower in RAS of the highest ER when compared to those reared under the 0.5 m3/kg feed. Results suggest an ER of 1.5 m^3 feed/kg improved both fish quality and growth profile of the gilthead bream.展开更多
基金Supported by the Science and Technology Plan of Qingdao(No.103-4-5-6-jch)the National Natural Science Foundation of China(No.31101916)+1 种基金the Natural Science Foundation of Shandong Province,China(No.ZR2010CM060)the University Student Innovation Plan of Qingdao Agricultural University(No.201030)
文摘Marsupenaeusjaponicus Bate is one of the most valuable cultured shrimp species in China and outdoor earthen pond farming is the most common method of culturing this organism. The need to increase soil usage efficiency in aquaculture has been recognized and a great deal of research effort has been directed toward development of super-intensive farming systems. However, current research and development in this field is largely devoted to Litopenaeus vannamei Boone, while to M.japonicus Bate it has been neglected. In this study, a layered fanning system was designed and a 66-day study was conducted in M.japonicus Bate culture. The system comprised bracket and sand layers that divided a shrimp tank filled to a depth of 1.2 m into four water layers. Conventional tank culture （unlayered） was used as a control. The results show that survival rate, feed conversion efficiency and production of M.japonicus Bate in the layered farming system were 68%, 18%, and 0.59 kg/m^2, respectively, all of which are significantly higher than in the unlayered fanning system （P〈0.01）. These findings confirmed the possibility of using a layered system to culture M. japonicus Bate.
基金Supported by the State Key Laboratory of Freshwater Ecology and Biotechnology of China and Shanghai Fisheries University (Grant No. 200015).
文摘Hybrid tilapia weighing 7.71 g were reared in seawater at 24.0-29.0℃ for 8 weeks. The controls were fed to satiation twice a day throughout the experiment, whereas treatment groups were fed at 0.5%, 1.5% or 3.0% body weight per day for 4 weeks, and then to satiation for the remainder of the experiment. During the first 4-week period, there was a curvilinear relationship between growth rate and ration size. Fish fed 0.5% and 1.5% rations displayed compensatory growth response of 2 weeks duration during realimentation. The weight-adjusted growth rate of fish fed at 3% ration was not significantly different from that of the controls by the end of the experiment, when none of the treatment groups had caught up in body weight with the controls. Hyperphagia was observed for the first 2 weeks of realimenatation in fish previously fed at 3% ration, but persisted for the whole realimentation period in groups previously fed at 0.5% and 1.5% rations. None of the feed restricted groups showed improved digestibility, feed efficiency, or protein and energy retention efficiency.
基金Supported by NSFC (No.40206001), and the Key Laboratory of Mariculture of Ministry of Education, Ocean University of China (No.200404).
文摘Experiment on phosphorus budget of redeye mullet (Liza haematocheila T. & S.) was con- ducted at water temperature 21℃ and salinity 33. The results showed that the growth phosphorus (phosphorus that allocated into growth, GP) increased from –30.84% to 15.83% by feeding on graded amount of diets (starvation, 1%, 2%, 3%, 4% body weight and satiation). The GP linearly increased with feeding levels (FL) as GP (mg) =–0.785 + 0.604 FL, and at satiation the relationship between GP and body weight (BW) was GP (mg) = 1.5991 BW 0.768 5. In the budget, IP (intake phosphorus) = GP + FP (faecal phosphorus) + EP (excretion phosphorus). FP showed an irregular tendency with different feeding levels, and EP decreased with increasing feeding levels but rebound at satiation. The P budget at satiation was 100IP = 15.84 GP + 64.62 FP + 19.55 EP.
基金Supported by the Key Projects of the National Science and Technology Pillar Program during the 12th Five-year Plan Period(Nos.2011BAD13B02,2012BAD18B03)the Science and Technology Promoting Projects for Oceanic and Fishery in Guangdong Province(Nos. A201100D01,A201101D02)
文摘The seaweed Sargassum hemiphyllum is widely distributed throughout the coastal waters of Asia and has high commercial value. In recent years, its natural biomass has declined due to over-exploitation and environmental pollution. To seek for a feasible way to culture this seaweed efficiently, we designed a simple long-line system in a shrimp pond for the culture during winter, and the growth and nutritional composition of the seaweed were examined. Results show that the cul^re system was durable and flexible allowing S. hemiphyllum to grow vertically offthe muddy bottom of the pond. Although the length of pond- cultured S. hemiphyllum was inhibited by water depth, the weight-specific growth rate （（1.65±0.17）%/d） was nearly three times higher than that of wild plants （（0.62±0.19）%/d）. The crude protein （6.92%±0.88%） and ash content （21.52%±0.07%） of the pond-cultured seaweed were significantly lower than those of the wild plants （9.38%±-0.43% and 26.93%±0.07%, respectively）; however, crude fat （1.01%±0.04%） was significantly higher than that of the wild plants （0.87%±0.02%）. In addition, the nutritional composition of both pond-cultured and wild S. hemiphyllum was comparable to or even higher than those of other common seaweeds being used as food and/or aquaculture fodder. Future studies shall be focused on the impact of environmental parameters on its growth and nutritional composition.
文摘This study was designed to compare the effect of two exchange rates （ERs; 0.5 m^3 feed/kg and 1.5 m^3 feed/kg） in re-circulating aquaculture systems （RAS） on water quality and fish growth profiles on fish stocks （200 indiv/m^3 of 251.4 g e 20.67 g） of gilthead bream, Sparus aurata. Water quality, fish growth, specific growth rate （SGR） and feed conversion ratio under the two ERs were examined for a period of six months. Inorganic nutrient in RAS, temperature, dissolved oxygen and pH were measured daily. Feeding regime effect was also determined on the fish quality and organoleptic characteristics and thus opts to energy optimization of the system. The fish reared under the 1.5 m^3 feed/kg ER demonstrate enhanced growth, the daily SGR and the conversion ratio. Sensory test analysis revealed differences in the organoleptic characteristics between the two experimental fish stocks with considerably high acceptance scores for fish reared at high ER. Nutrient concentrations： ammonia, nitrate, nitrite and phosphate were lower in RAS of the highest ER when compared to those reared under the 0.5 m3/kg feed. Results suggest an ER of 1.5 m^3 feed/kg improved both fish quality and growth profile of the gilthead bream.
