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山瑞鳖与中华鳖的养殖生长和形态比较 被引量:3
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作者 郑文彪 粱淡茹 +4 位作者 肖智 方昆阳 刘顺元 林蠡 孟帆 《淡水渔业》 CSCD 北大核心 1998年第1期40-41,共2页
山瑞鳖与中华鳖的养殖生长和形态比较@郑文彪@粱淡茹@肖智@方昆阳¥华南师范大学生物系@刘顺元@林蠡@孟帆¥广东省海洋与水产厅资源环境管理处山瑞鳖与中华鳖的养殖生长和形态比较郑文彪粱淡茹肖智方昆阳(华南师范大学生物系,... 山瑞鳖与中华鳖的养殖生长和形态比较@郑文彪@粱淡茹@肖智@方昆阳¥华南师范大学生物系@刘顺元@林蠡@孟帆¥广东省海洋与水产厅资源环境管理处山瑞鳖与中华鳖的养殖生长和形态比较郑文彪粱淡茹肖智方昆阳(华南师范大学生物系,广州510631)刘顺元林蠡孟帆(广东省... 展开更多
关键词 山瑞鳖 中华鳖 养殖生长 形态比较
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贝类养殖可持续发展能力的生态制约 被引量:3
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作者 刘岗 《海水养殖》 2000年第1期47-53,共7页
关键词 海水贝类养殖 可持续发展 养殖生长预测 养殖容量 食物 生物附着 混养
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工厂化养殖对虾的促长与病害防治
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作者 陈剑锋 《科学养鱼》 2002年第4期42-43,共2页
关键词 工厂化养殖 对虾 病害防治 生长养殖 高密度精养 虾壳偏软
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Porcine Breeding Management in a Large-scale Piggery with Microbial Fermentation Bed 被引量:1
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作者 刘波 李兆龙 +6 位作者 唐建阳 黄勤楼 郑回勇 蓝江林 史怀 翁伯琦 余文权 《Agricultural Science & Technology》 CAS 2015年第1期160-166,171,共8页
[Objective] The behavior of eating, drinking, defecating and peeing of 1 500 pigs in a large-scale microbial fermentation bed-equipped piggery was observed. We hoped to find some simple indicators that could reflect t... [Objective] The behavior of eating, drinking, defecating and peeing of 1 500 pigs in a large-scale microbial fermentation bed-equipped piggery was observed. We hoped to find some simple indicators that could reflect the health status of swinery and to provide experience for the swinery performance management in large-scale microbial fermentation bed-equipped piggery. [Method] The body weight (BW), daily BW gain, feed intake and other indicators of different-day-old pigs were recorded in details. Based on the recorded data, the models between BW, BW gain, average daily feed intake and feed/gain ratio and growth days (d) were established. In addition, the incidences of pox-like macula (dermatitis), diarrhea (gastrointestinal disease), cough (respiratory disease), stiff pig (malnutrition), conjunctivitis (eye disease) and foot inflection (trauma) among fattening pigs were also investigated. [Result] The BW range, average BW, daily BW gain, breeding days, daily feed intake range, average daily feed intake, staged feed intake, accumulated feed intake, feed/gain ratio and accumulated feed/gain ratio of different-day-old pigs were studied, respectively. Four dynamic models were established for the growth of pigs: (1) the BW (y)-age (x) mod- el: y=0.758 9x-19.883 (3=0.993 7); (2) the BW gain (y)-age (x) model: y=1.039 5x05051 (F=0.885 4); (3) the average daily feed intake (y)-age (x) model: y=0.023 5x-0.334 3 (F=0.991 7); (4) the feed/gain ratio (y)-age (x) model: y=0.022x+0.427 8 (P=0.988 5). Based on these models, the corresponding theoretical growth value of pigs at different growth stage could be predicted. The main diseases occurred among the swinery in the large-scale microbial fermentation bed piggery included pox-like macula (dermatitis), diarrhea (gastrointestinal disease), cough (respiratory disease), stiff pig (mal- nutrition), conjunctivitis (eye disease) and foot inflection (trauma). The deadly infec- tious diseases had been not found among the pigs. [Conclusion] When the actual BW, BW gain, average daily feed intake and feed/gain ratio were all lower than the theoretical values predicted by the models, the management should be enhanced. The average daily feed intake of 60 to 65-day-old pigs was lower than the theoretic value, indicating that the pigs could not adapt nicely to the fermentation bed at the very early stage. When the pigs grew up to 70 to 75 d old, the average daily feed intake was higher than the theoretical value, indicating that the pigs had adapted to the fermentation bed. In particularly, average daily feed intake of 75-day-old pigs was higher than the theoretical value by 21%. It was suggested the fermentation bed was conducive to the growth of pigs. Considering the occurrence of diseases among pigs, the overall incidence was relatively low. The incidence of each disease was all lower than 10% with little difficulty in treating. If the management of mattress was strength- ened, such as paying attention to feeding and keeping water clean, many diseases could heal by themselves. 展开更多
关键词 Disease investigation Large-scale breeding Microbial fermentation bed Porcine growth model
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改造沙漠的太阳能综合体
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作者 远一 《世界农业》 1988年第10期56-56,共1页
苏联阿什哈贝达太阳能联合公司已开始在契尔卡兹里沙漠地区建造太阳能综合体。综合体内包括太阳能机井、给水系统、住宅、空调和制冷以及栽培蔬菜和饲料绿球藻的温室。其中温室设施尤为重要,它不仅要供给人们吃菜,而且要养殖生长极快的... 苏联阿什哈贝达太阳能联合公司已开始在契尔卡兹里沙漠地区建造太阳能综合体。综合体内包括太阳能机井、给水系统、住宅、空调和制冷以及栽培蔬菜和饲料绿球藻的温室。其中温室设施尤为重要,它不仅要供给人们吃菜,而且要养殖生长极快的绿球藻来作为牲畜饲料。综合体的全部设施都利用沙漠地带丰富的太阳能资源。 展开更多
关键词 太阳能 综合体 给水系统 养殖生长 沙漠地区 饲料 联合公司 温室设施 太阳能资源 苏联
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改造沙漠的太阳能综合体
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《世界农业》 1986年第12期17-17,共1页
苏联阿什哈贝达太阳能联合公司已开始在契尔卡兹里沙漠地区建造太阳能综合体。综合体内包括太阳能机井、给水系统、住宅、空调和制冷以及栽培蔬菜和饲料绿球藻的温室。其中温室设施尤为重要,它不仅要供给人们吃菜。
关键词 太阳能 综合体 蔬菜和饲料 给水系统 沙漠地带 养殖生长 温室设施 沙漠地区 联合公司 太阳能资源
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REDUCED GROWTH IN HYBRID TILAPIA (OREOCHROMIS MOSSAMBICUS×O. NILOTICUS) AT INTERMEDIATE STOCKING DENSITY 被引量:2
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作者 王岩 崔奕波 +1 位作者 杨云霞 蔡发盛 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第4期344-347,共4页
Hybrid tilapia were reared at densities of 1, 5 or 10 fish per tank for four weeks. Mortality was 0 at 1 and 10 fish per tank, but was 25% at 5 fish per tank. Specific growth rate was highest at 1 fish per tank, and l... Hybrid tilapia were reared at densities of 1, 5 or 10 fish per tank for four weeks. Mortality was 0 at 1 and 10 fish per tank, but was 25% at 5 fish per tank. Specific growth rate was highest at 1 fish per tank, and lowest at 5 fish per tank. The lower growth rate at the intermediate stocking density was associated with reduced feed efficiency, but there was no reduction in feed intake or digestibility. The results suggested increased metabolic cost caused by aggressive behaviour at intermediate stocking density, which can be suppressed by a further increase in density. 展开更多
关键词 GROWTH feed efficiency stocking density TILAPIA
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Glutamate dehydrogenase and Na^+-K^+ ATPase expression and growth response of Litopenaeus vannamei to different salinities and dietary protein levels 被引量:2
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作者 李二超 Leticia ARENA +5 位作者 Gabriel LIZAMA Gabriela GAXIOLA Gerard CUZON Carlos ROSAS 陈立侨 Alain VAN WORMHOUDT 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第2期343-349,共7页
Improvement in the osmoregulation capacity via nutritional supplies is vitally important in shrimp aquaculture.The effects of dietary protein levels on the osmoregulation capacity of the Pacific white shrimp(L.vanname... Improvement in the osmoregulation capacity via nutritional supplies is vitally important in shrimp aquaculture.The effects of dietary protein levels on the osmoregulation capacity of the Pacific white shrimp(L.vannamei) were investigated.This involved an examination of growth performance,glutamate dehydrogenase(GDH) and Na+-K+ ATPase mRNA expression,,and GDH activity in muscles and gills.Three experimental diets were formulated,containing 25%,40%,and 50% dietary protein,and fed to the shrimp at a salinity of 25.After 20 days,no significant difference was observed in weight gain,though GDH and Na+-K+ ATPase gene expression and GDH activity increased with higher dietary protein levels.Subsequently,shrimp fed diets with 25% and 50% dietary protein were transferred into tanks with salinities of 38 and 5,respectively,and sampled at weeks 1 and 2.Shrimp fed with 40% protein at 25 in salinity(optimal conditions) were used as a control.Regardless of the salinities,shrimp fed with 50% dietary protein had significantly higher growth performance than other diets;no significant differences were found in comparison with the control.Shrimp fed with 25% dietary protein and maintained at salinities of 38 and 5 had significantly lower weight gain values after 2 weeks.Ambient salinity change also stimulated the hepatosomatic index,which increased in the first week and then recovered to a relatively normal level,as in the control,after 2 weeks.These findings indicate that in white shrimp,the specific protein nutrient and energy demands related to ambient salinity change are associated with protein metabolism.Increased dietary protein level could improve the osmoregulation capacity of L.vannamei with more energy resources allocated to GDH activity and expression. 展开更多
关键词 Litopenaeus vannamei gene expression glutamate dehydrogenase Na^+-K^+ ATPase PROTEIN SALINITY
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Effects of lithium on the survival,growth,and reproduction of Daphniopsis tibetana Sars(Crustacea:Cladocera) 被引量:1
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作者 赵文 霍元子 +2 位作者 张天民 王珊 石婷婷 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第4期754-762,共9页
We evaluated the effects of lithium on the survival, growth, and reproduction ofD. tibetana in the laboratory. The safe concentration value was 69.3 mg/L. The time to first brood was significant lower for individuals ... We evaluated the effects of lithium on the survival, growth, and reproduction ofD. tibetana in the laboratory. The safe concentration value was 69.3 mg/L. The time to first brood was significant lower for individuals reared in 5 and 10 mg/L (24.4 and 24.0 d, respectively) compared with individuals reared in 20, 40, or 60 mg/L. Females reared in 5 mg/L lithium produced a mean of 16.5 neonates/brood and had the highest number of broods (3.0±1.95). The rate of egg production (a), the intrinsic rate of increase (rm), net reproduction rate (R0), and finite rate of increase (2) were highest for D. tibetana reared at 5 and 10 mg/L lithium, and the duration of development was shorter than for the remaining groups. The results indicated that rearing in 5 10 mg/L lithium can accelerate the growth and reproduction ofD. tibetana. 展开更多
关键词 LITHIUM toxicity GROWTH REPRODUCTION Daphniopsis tibetana Sars
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Effects of Stocking Density on Water Quality,Growth and Economic Benefits of Chinese Softshelled Turtle Pelodiscus sinensis in Ponds
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作者 Wei LI Huaiyu DING +3 位作者 Fengyin ZHANG Tanglin ZHANG Jiashou LIU Zhongjie LI 《Agricultural Science & Technology》 CAS 2016年第5期1238-1242,共5页
The Chinese soft-shelled turtle Pelodiscus sinensis is a high-valued freshwater species cultured in China.This study investigated the effects of stocking density on water quality,growth performance and economic return... The Chinese soft-shelled turtle Pelodiscus sinensis is a high-valued freshwater species cultured in China.This study investigated the effects of stocking density on water quality,growth performance and economic return of Pelodiscus sinensis cultured in ponds.P.sinensis were stocked at densities of 1 ind./m^2(LD:low stocking density) and 2 ind./m^2(HD:high stocking density) in 3 000-m^2 ponds,with three replicate ponds for each density.P.sinensis juveniles were fed with a commercial dry pellet feed of 46% crude protein and minced fillet of silver carp ans cultured for 122 days.The results showed that the levels of total nitrogen(TN),total phosphorous(TP),Chlorophyll-a(Chl.a) and turbidity in LD treatment were significantly lower than those in HD treatment(P<0.05).The mean TN and TP concentration in LD treatment was 29.3% and 35.7% lower compared to the HD treatment at the end of the experiment,respectively.Mean survival rates,final weight,average growth rates and PER were significantly higher in LD treatment compared with the HD treatment(P<0.05),respectively.Production was significantly affected by stocking density,which was higher in HD treatment,but the net income was higher in LD treatment.The results suggest that turtles with mean weight 55.6 g rearing at a low stocking density(1 ind./m^2) in ponds had a positive effect on overall economic return and was effective at improving turtle growth performance and water quality. 展开更多
关键词 Pelodiscus sinensis Stocking density Water quality Growth performance Economic return
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Culture techniques and growth characteristics of Dinophysis acuminata and its prey 被引量:1
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作者 佟蒙蒙 周启星 +3 位作者 KULIS M.David 江天久 齐雨藻 ANDERSON M.Donald 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第6期1230-1239,共10页
The dinoflagellate Dinophysis acurninata Claparede & Lachrnann is a toxic alga that causes diarrhetic shellfish poisoning. No Dinophysis species were maintained in culture for a long period of time until 2006 when Pa... The dinoflagellate Dinophysis acurninata Claparede & Lachrnann is a toxic alga that causes diarrhetic shellfish poisoning. No Dinophysis species were maintained in culture for a long period of time until 2006 when Park successfully established D. acuminata in culture using a three-step feeding protocol in which the cryptophyte, Geminigera cryophila, is fed to Myrionecta rubra (=Mesodinium rubrum), a ciliate that is in turn fed to D. acuminata. In this paper, we present the details of culturing D. acuminata from the Northeastern United States. The protocols described herein can be adopted for laboratory studies of this species. The effects of temperature on the growth and ingestion rates of D. acuminata were also examined. The results show that D. acuminata growth rate was 0.23/d at 10℃ and 0.11/d at 4℃when fed M. rubra prey. The maximum prey ingestion rate was 2.80 Dinophysis cell/d at 10℃, although the rate decreased slightly at 4℃. In overall, temperature showed a greater influence on growth rate of D. acuminata than on the ingestion rate under the study conditions, and the quantity of available food was also an important regulator to D. acurninata growth. 展开更多
关键词 Dinophysis acuminata Myrionecta rubra Geminigera cryophila growth rate ingestion rate
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Phosphorus budget of redeye mullet (Liza haematocheila T. & S.) under graded feeding levels
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作者 康斌 线薇薇 武云飞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2006年第3期313-317,共5页
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
关键词 phosphorus budget feeding level GROWTH Liza haematocheila
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Growth Profile of Gilthead Bream Reared in Mega Flow Re-circulating Aquaculture System
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作者 Mohammad Al-Zibdah 《Journal of Agricultural Science and Technology(A)》 2014年第4期307-314,共8页
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
关键词 RAS gilthead sea bream ER GROWTH conversion rate.
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Ecological functions of ciliated protozoa in marine ecosystem: effects of ammonium on the population growth of Euplotes vannus 被引量:1
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作者 许恒龙 Song Weibo +3 位作者 Zhu Mingzhuang Wang Mei Ma Honggang Xu Xiaozhong 《High Technology Letters》 EI CAS 2005年第4期432-436,共5页
The effects of ammonium on the population growth of the marine ciliate, Euplotes vannus, were examined using ecotoxicological method, h is showed that ammonium exerts inhibitory effects on the growth of the ciliate po... The effects of ammonium on the population growth of the marine ciliate, Euplotes vannus, were examined using ecotoxicological method, h is showed that ammonium exerts inhibitory effects on the growth of the ciliate populations in a concentration-dependent way. Statistical analvsis reveals that the population growth dynamics exposed to ammoniunt-N concentration over 100mg/L are significantly different from that in the control at P 〈 0.05 level. Linear regression determined that the 24h, 36h, 48h, 60h, 72h and 84h IC50 values of ammonium-N are 19.68, 201.51, 167.49, 47.86, 50.43 and 43.11 concentration over 100mg/L, respectively ( P 〈 0.05; pH 8.2; salinity 28 ppt; temperature, 25℃ ). The results indicate that the tolerance to ammonium in E. vannus is considerably higher than that of the larvae or juveniles of some metozoa, such as cuhured prawns and oysters. Therefore, it is believed that the high tolerance to ammonium is necessary for eiliated protozoa to play positive roles in maintaining and improving water quality in marine ecosystems, especially in the intensive aquacuhure waters with high-level ammonium. In addition, the correlation between /C50 values and exposure time was discussed. 展开更多
关键词 marine ciliates growth response AMMONIA MARICULTURE ECOTOXICOLOGY
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Responses to two-way selection on growth in mass-spawned F_1 progeny of Argopecten irradians concentricus(Say)
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作者 王辉 刘进 +2 位作者 李艳红 朱晓闻 刘志刚 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第2期349-357,共9页
In the present study, the effect of one-generation divergent selection on the growth and survival of the bay scallop (Argopecten irradians concentricus) was examined to evaluate the efficacy of a selection program c... In the present study, the effect of one-generation divergent selection on the growth and survival of the bay scallop (Argopecten irradians concentricus) was examined to evaluate the efficacy of a selection program currently being carried out in Beibu Bay in the South China Sea. A total of 146 adult scallops were randomly selected from the same cultured population ofA. i. concentricus, and divided into two groups in shell length (anterior-posterior measurement): large (4.91-6.02 cm, n=74) and small (3.31-4.18 cm, n=72). At the same time, a control group was also randomly sampled (4.21-4.88 cm, n=80). Mass-spawned F1 progenies from the three size groups were obtained and reared under identical conditions at all growth phases. The effects of two-way (or upward-downward) selection on fertilization rate, hatching rate, survival rate, daily growth in shell length and body weight were assessed in the three size groups. Results show that significant differences (P〈0.01) were found in hatching rate, survival rate and daily growth of F~ progenies, but not in fertilization rate (P〉0.05), among the three groups. The hatching rate, survival rate and daily growth of the progeny of large-sized parents were greater than those of the control group (P〈0.05), which in turn were larger than those of small-sized group (P〈0.05). Responses to selection by shell length and body weight were 0.32±0.04 cm and 2.18±0.05 g, respectively, for the upward selection, and -0.14±0.03 cm and -2.77±0.06 g, respectively, for the downward selection. The realized heritability estimates of shell length and body weight were 0.38±0.06 cm and 0.22±0.07 g for the upward selection, and 0.24±0.06 cm and 0.37±0.09 g for the downward selection, respectively. The change in growth by bidirectional selection suggests that high genetic variation may be present in the cultured bay scallop population in China. 展开更多
关键词 Argopecten irradians concentricus (Say) two-way selection response to selection realized heritability F1 progeny mass-spawned
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Feed, Feeding and Environment Safety in Aquaculture
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作者 XIE S. 《Feed & Livestock》 2010年第3期8-8,共1页
With fast increase in aquaculture, there comes the environmental problems which have received most attentions. The pollution from aquaculture includes nitrogen and phosphorus loading, unexpected chemicals and organism... With fast increase in aquaculture, there comes the environmental problems which have received most attentions. The pollution from aquaculture includes nitrogen and phosphorus loading, unexpected chemicals and organisms. Poor water environment not only resulted in poor growth efficiency of fish, but also in poor fish quality and high risk of diseases. 展开更多
关键词 FEED FEEDING Environment safety
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Evaluation of Feed and Feeding Regime on Growth Performance, Flesh Quality and Fecal Viscosity of Atlantic Salmon(Salmo salar L.) in Recirculating Aquaculture Systems
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作者 SUN Guoxiang LIU Ying +2 位作者 LI Yong LI Xian WANG Shunkui 《Journal of Ocean University of China》 SCIE CAS 2015年第5期849-857,共9页
The effects of different feeds and feeding regimes on growth performance, flesh quality and fecal viscosity of Atlantic salmon (Salmo salar L.) in recirculating aquaculture systems (R.AS) were investigated. Fish ... The effects of different feeds and feeding regimes on growth performance, flesh quality and fecal viscosity of Atlantic salmon (Salmo salar L.) in recirculating aquaculture systems (R.AS) were investigated. Fish (initial body weight of 1677 g+ 157 g) were fed with four commercial feeds (Nosan salmon-NS, Aller gold-AG, Skretting salmon-SS and Hart ye-HY) in two feeding regimes (80% and 100% satiation) for 78 d. The results showed that salmon specific growth ratio (SGR) and weight gain ratio (WGR) were significantly affected by feed type and feeding regime (P〈0.05). Feed conversion ratio (FCR) varied between 0.93 and 3.40, which was significantly affected by feed type (P〈0.05), and slightly improved with increased satiation degree. The activities of digestive enzymes including protease, lipase and amylase were also significantly affected by feed type and feeding regime (P〈0.05), increasing with satiation degree. Flesh qualities for vitamin E, hydroxyproline (HYP), liquid loss and muscle pH among all groups showed significant differences (P〈0.05), ranging from 26.67 to 29.67, while no obvious difference was found in flesh color. Fecal viscosity for different treatments showed no significant difference, though improvement was found in 100% satiation group. From present experiment, it was concluded that both feed type and feeding regime can affect the important quality attributes of Atlantic salmon. 展开更多
关键词 Atlantic salmon Salmo salar L. recireulating aquaculture systems R.AS FEED feeding growth flesh quality fecal viscosity
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Seasonal Variations in Serological Profiles and Growth Status of Farmed and Wild Clarias gariepinus (Burchell, 1822) Obtained from Asaba, Nigeria
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作者 Agatha Arimiche Nwabueze Juliana Regha-John 《Journal of Agricultural Science and Technology(B)》 2015年第3期205-215,共11页
Seasonal variations in serological profiles and growth status of farmed and wild Clarias gariepinus were investigated. Serological profiles of Clarias gariepinus can be an effective tool for proper monitoring of stres... Seasonal variations in serological profiles and growth status of farmed and wild Clarias gariepinus were investigated. Serological profiles of Clarias gariepinus can be an effective tool for proper monitoring of stress induced by management practices in intensive fish culture, which may elicit devastating effect on fish. Spectrophotometry procedures were used to analyze serum parameters of Clarias gariepinus. No different seasonal patterns were observed for mean values of albumin, total protein, urea, cholesterol, glucose and alanine amino-transferase. However, aspartate amino-transferase showed different seasonal pattern. Levels of cholesterol and alanine amino-transferase were highly significant in farmed and wild fish, separately. Juvenile fish had high level of urea irrespective of season. Seasonal variations in water quality parameters were observed except for pH which had no seasonal pattern. The growth exponential shows b-values between -0.048 and 7.434 for Clarias gariepinus. Adult female and juvenile fish from the wild had the highest b-value and the least b-value, separately. In this study, b-values were higher in the wild fish than the farmed fish. The condition factor for Clarias gariepinus ranged from 0.422 to 0.698, and was observed to be high in juvenile fish. With a condition factor less than 1, fish may not be doing well, probably due to environmental stress. Some serological parameters varied according to season and environment of fish. Thus, serological profile of fish is an effective and sensitive tool to monitor fish response to stress factors in the environment. 展开更多
关键词 SEROLOGY Clarias gariepinus farmed fish wild fish Asaba Nigeria.
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Pond culture of seaweed Sargassum hemiphyllum in southern China
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作者 于宗赫 胡超群 +2 位作者 孙红岩 李海鹏 彭鹏飞 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第2期300-305,共6页
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
关键词 Sargassum hemiphyllum GROWTH nutritional composition AQUACULTURE
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Contribution of Root Proliferation in Nutrient-Rich Soil Patches to Nutrient Uptake and Growth of Maize 被引量:19
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作者 LI Hong-Bo ZHANG Fu-Suo SHEN Jian-Bo 《Pedosphere》 SCIE CAS CSCD 2012年第6期776-784,共9页
Root proliferation can be stimulated in a heterogeneous nutrient patch; however, the functions of the root proliferation in the nutrient-rich soil patches are not fully understood. In the present study, a two-year fie... Root proliferation can be stimulated in a heterogeneous nutrient patch; however, the functions of the root proliferation in the nutrient-rich soil patches are not fully understood. In the present study, a two-year field experiment was conducted to examine the comparative effects of localized application of ammonium and phosphorus (P) at early or late stages on root growth, nutrient uptake, and biomass of maize (Zea mays L.) on a calcareous soil in an intensive farming system. Localized supply of ammonium and P had a more evident effect on shoot and root growth, and especially stimulated fine root development at the early seedling stage, with most of the maize roots being allocated to the nutrient-rich patch in the topsoil. Although localized ammonium and P supply at the late stage also enhanced the fine root growth, the plant roots in the patch accounted for a low proportion of the whole maize roots in the topsoil at the flowering stage. Compared with the early stage, fine root length in the short-lived nutrient patch decreased by 44%-62% and the shoot dry weight was not different between heterogeneous and homogeneous nutrient supply at the late growth stage. Localized supply of ammonium and P significantly increased N and P accumulation by maize at 35 and 47 days after sowing (DAS); however, no significant difference was found among the treatments at 82 DAS and the later growth stages. The increased nutrient uptake and plant growth was related to the higher proportion of root length in the localized nutrient-enriched patch. The results indicated that root proliferation in nutrient patches contributed more to maize growth and nutrient uptake at the early than late stages. 展开更多
关键词 biomass growth stage intensive farming system localized nutrient supply root length
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