Sri Lanka Journal of Aquatic Sciences最新文献_第10页

Effects of dried, powdered carrot (Daucus carota) incorporated diet on the skin and flesh colouration of Catla catla 干胡萝卜粉(Daucus carota)添加饲料对卡特拉(Catla Catla)皮肤和果肉颜色的影响

Sri Lanka Journal of Aquatic Sciences Pub Date : 2016-06-24 DOI: 10.4038/SLJAS.V21I2.7505

W. Weerakkody, P. Cumaranatunga

{"title":"Effects of dried, powdered carrot (Daucus carota) incorporated diet on the skin and flesh colouration of Catla catla","authors":"W. Weerakkody, P. Cumaranatunga","doi":"10.4038/SLJAS.V21I2.7505","DOIUrl":"https://doi.org/10.4038/SLJAS.V21I2.7505","url":null,"abstract":"Dull yellow coloured flesh of C. catla is less attractive to the consumer. Present study investigated the effects of dried, powdered carrot incorporated feed as a source of carotenoids on pigmentation and sensory properties of C. catla skin and flesh. Two groups of C. catla fingerlings (4.39±0.13 cm and 2.41±0.13 g) were fed with a commercially available feed (CF) incorporated with 100 mg/kgdried and ground D. carota , sieved using 250 μm (CF+C1) and 450 μm (CF+C2) mesh and it was compared with a control group of fish of the same size fed with CF. Each group included three replicates of 10 fish. Fish were fed ad libitum thrice daily for 10 weeks. Total carotenoid content in flesh and skin, average daily gain (% ADG), specific growth rate (% SGR), feed conversion ratio (FCR), hepato-somatic index (HSI), daily feed consumption (g/day/tank) and survival rate of fish were analysed at the end of the experiment. A sensory evaluation of fish flesh was done by a panel of judges. It was revealed that D. carota incorporated feed CF+C1, CF+C2 provided a significantly higher carotenoid accumulation by wet weight in flesh (1.36±0.11 and 1.19±0.09 μg/g, respectively) and in skin (2.79±0.08 and 2.82±0.06 μg/g, respectively), compared to flesh (0.45±0.04 μg/g) and skin (0.72±0.14 μg/g) of the CF fed fish. There were no significant differences (p>0.05) among the two experimented groups in the average weight, % SGR, daily feed consumption and % ADG at the end of experiment. Significantly lower FCR was observed in CF+C1 and CF+C2 fed fish (3.90±0.27, 3.98±0.68, respectively) when compared to fish fed with CF (4.91±0.39). Sensory analysis revealed that the flesh of fish fed with D. carota predicate a bright pink colour and was preferred, compared to the flesh of control group.","PeriodicalId":21784,"journal":{"name":"Sri Lanka Journal of Aquatic Sciences","volume":"22 1","pages":"95"},"PeriodicalIF":0.0,"publicationDate":"2016-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72769481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Toxicity of aqueous extract of white hoary pea, Tephrosia candida (Papilionoideae) on Nile tilapia, Oreochromis niloticus (Cichlidae) fingerlings 白豌豆白色念珠菌(凤蝶科)水提物对尼罗罗非鱼鱼苗的毒性研究

Sri Lanka Journal of Aquatic Sciences Pub Date : 2016-06-24 DOI: 10.4038/SLJAS.V21I2.7506

C. Mohotti, U. Epa

{"title":"Toxicity of aqueous extract of white hoary pea, Tephrosia candida (Papilionoideae) on Nile tilapia, Oreochromis niloticus (Cichlidae) fingerlings","authors":"C. Mohotti, U. Epa","doi":"10.4038/SLJAS.V21I2.7506","DOIUrl":"https://doi.org/10.4038/SLJAS.V21I2.7506","url":null,"abstract":"Fish poisoning using Tephrosia candida , which is an exotic plant to Sri Lanka is taking place in streams in the boundary of the Sinharaja forest, a tropical forest range, designated as a world heritage site by UNESCO in 1988. T. candida is a source of flavonoids and rotenoids including rotenone, tephrosin, and deguelin. Fishermen add large amounts of grounded plant matter to kill almost all the fishes in the stream within a short period of time. This method of unregulated fishing may have a long term negative effect on fish diversity and abundance in the area. A 96 h static renewal toxicity bioassay was carried out in the laboratory to determine the median lethal concentration (LC 50 ) of aqueous extract of T. candida leaves on Oreochromis niloticus fingerlings. Experimental fish were exposed to test water in 20 L glass aquaria with concentrations of plant extract of 5, 7.5, 10, 15 and 20 mg L -1 . All five treatments aquaria and the control aquaria without plant extract were triplicated. Fish exposed to plant extract showed symptoms of toxicity including, initial inactivation, agitated swimming, turning movement, air gulping, increased opercular movement followed by erratic swimming, loss of reflex, slow opercular movement, setting at the bottom motionless and knockdown before death. The gills of the dead fishes were damaged, swollen and external bleeding were observed. Lower concentrations of the extracts had sub lethal effects which manifested as zigzag movement, air gulping, increased opercular movement and some fish gathered near the air stones. The LC 50 values at various exposure periods were 10.83 mg L -1 for 24 h; 8.61 mg L -1 for 48 h; 7.26 mg L -1 for 72 h and 6.43 mg L -1 for 96 h. It could be concluded that the application of T. candida extract causes lethal toxic effects on fish even at very low concentrations.","PeriodicalId":21784,"journal":{"name":"Sri Lanka Journal of Aquatic Sciences","volume":"123 1","pages":"105"},"PeriodicalIF":0.0,"publicationDate":"2016-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76722385","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Farming of Nile tilapia (Oreochromis niloticus) in backyard ponds in Sri Lanka: Culture practices, fish production and profitability 斯里兰卡后院池塘尼罗罗非鱼养殖:养殖实践、鱼类生产和盈利能力

Sri Lanka Journal of Aquatic Sciences Pub Date : 2016-02-20 DOI: 10.4038/SLJAS.V21I1.7483

K. Pushpalatha, J. Chandrasoma, H. Liyanage, W. Fernando, J. Jayabahu

{"title":"Farming of Nile tilapia (Oreochromis niloticus) in backyard ponds in Sri Lanka: Culture practices, fish production and profitability","authors":"K. Pushpalatha, J. Chandrasoma, H. Liyanage, W. Fernando, J. Jayabahu","doi":"10.4038/SLJAS.V21I1.7483","DOIUrl":"https://doi.org/10.4038/SLJAS.V21I1.7483","url":null,"abstract":"Government of Sri Lanka through Ministry of Economic Development implemented an island-wide multi-sector programme during 2011-2014 involving rural households with the objective of enhancing nutrition and also to provide supplementary income and livelihoods. Fish farming in backyard/home garden ponds was one of the components under this programme. This was the second attempt by the government to introduce small- scale pond fish farming in Sri Lanka, and the first attempt made during 1980-1983 was a failure. A total of 2,109 ponds covering an area of 105.45 ha have been established under the current programme. Information pertaining to culture practices, fish production, financial returns and costs involved in respect of these ponds were collected through administering a questionnaire. The survey covered fish ponds in the districts of Gampaha, Puttalam and Ampara. Nile Tilapia ( Oreochrimis niloticus ) was the only species used for farming. All-male or mixed sex tilapia are being farmed in these ponds. Considerable variations in stocking densities adapted, inputs, fish production, selling prices of fish, operational costs and profitability was observed among ponds in these districts. Average fish production per culture cycle were 9,192 kg/ha (Gampaha), 6,074 kg/ha (Puttalam) and 3,270 kg/ha (Ampara). Tilapia farming in ponds is profitable in all three districts. Profit margins are very attractive in respect of ponds in Gampaha and Puttalam. Recommendations to ensure sustainability in tilapia farming in ponds and for further expansion of fish farming in ponds with special reference to culture practices, fish production, inputs and role of government are made.","PeriodicalId":21784,"journal":{"name":"Sri Lanka Journal of Aquatic Sciences","volume":"7 1","pages":"27"},"PeriodicalIF":0.0,"publicationDate":"2016-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86122999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Size-dependent dietary shifts in Chitala ornata (Osteichthyes; Notopteridae), an accidentally introduced exotic species in Sri Lanka 骨鱼Chitala ornata (Osteichthyes)的食性变化一种偶然引入斯里兰卡的外来物种

Sri Lanka Journal of Aquatic Sciences Pub Date : 2016-02-20 DOI: 10.4038/SLJAS.V21I1.7485

R.R.A.R. Shirantha

引用次数: 0

Cryptocoryne wendtii can successfully be grown in river sand enriched with nutrients 在富含营养物的河沙中可以成功地种植隐青菜

Sri Lanka Journal of Aquatic Sciences Pub Date : 2016-02-20 DOI: 10.4038/SLJAS.V21I1.7487

B. Bambaranda, S. Peiris

{"title":"Cryptocoryne wendtii can successfully be grown in river sand enriched with nutrients","authors":"B. Bambaranda, S. Peiris","doi":"10.4038/SLJAS.V21I1.7487","DOIUrl":"https://doi.org/10.4038/SLJAS.V21I1.7487","url":null,"abstract":"Cryptocoryne wendtii is commonly used for aquaria and water gardens and hence is an economically important aquatic plant with a high demand in local and export markets. There are fifty species of genus Cryptocoryne out of which fourteen species including C. wendtii are endemic to Sri Lanka. Although Sri Lanka exports around 300 aquatic plants, exportation of endemic and threatened species collected from the wild is prohibited, but the cultivated plants. C. wendtii (‘Brown’) shows poor growth when cultivated in common soil which is used for normal propagation of other ornamental aquatic plants. Hence, this study was undertaken to find an effective substratum for C. wendtii , which is important for aquatic plant industry. C. wendtii was grown in five different media prepared with top soil and river sand in different proportions, both under emerged and submerged conditions. Results were analyzed using one-way analysis of variance. Plants grown in river sand had the highest dry weight gain and percentage survival compared to plants grown in top soil and river sand media prepared according to 1:1, 1:2, 1:3 ratios irrespective of either they were grown emerged or submerged, demonstrating that river sand enriched with commercially available fertilizer is the best medium to grow C. wendtii .","PeriodicalId":21784,"journal":{"name":"Sri Lanka Journal of Aquatic Sciences","volume":"27 1","pages":"67"},"PeriodicalIF":0.0,"publicationDate":"2016-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84461432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Herklotsichthys quadrimaculatus Korumburuwa in the stilt fishery in Southern Sri Lanka: Are they really poisonous? 斯里兰卡南部的高跷渔场:它们真的有毒吗?

Sri Lanka Journal of Aquatic Sciences Pub Date : 2016-02-20 DOI: 10.4038/SLJAS.V21I1.7488

Upali Sarath Amarasinghe, U. K. Jayasinghe, S. Lanka.

{"title":"Herklotsichthys quadrimaculatus Korumburuwa in the stilt fishery in Southern Sri Lanka: Are they really poisonous?","authors":"Upali Sarath Amarasinghe, U. K. Jayasinghe, S. Lanka.","doi":"10.4038/SLJAS.V21I1.7488","DOIUrl":"https://doi.org/10.4038/SLJAS.V21I1.7488","url":null,"abstract":"Stilt fishing is a unique fish catching method confined only to southern coast of Sri Lanka from Galle to Matara. Stilt fishermen sitting on a cross bar called “Petta” tied to vertical pole planted in the reef and carrying out rod and line fishing are a Sri Lankan icon that attracts local and foreign tourists’ attention. This small-scale, seasonal fishing method has a long history and fishers use traditional ecological knowledge for their fishing activities (Deepananda et al. 2016). Two fish species, big eye scad ( Selar crumenophthamus ) locally known as Esgedi bolla and bluestripe herring ( Herklotsichthys quadrimaculatus ) locally known as Korumburuwa are caught by this fishing method. Of the two species, Korumburuwa is fished throughout the fishing season which commences from early June with the onset of southwest monsoon and continues until February/March of the following year. Due to freshness of the fish that can be bought at affordable price, most buyers prefer purchasing Korumburuwa at the place they are fished traditionally called as Rendapola. However, there is a traditional belief among some consumers that eating Korumburuwa causes some toxic effect leading to vomiting, dizziness and sometimes fainting among those who consume this species, and also deaths of domestic animals such as cats. These beliefs have detrimental impacts on the marketing of H. quadrimaculatus caught in stilt fishing. Such widespread beliefs may have been propagated rapidly among consumers through electronic mass media. For instance, recent media reports on fish poisoning by Auxis thazard in Muttur and observation of bioluminescence in Decapterus ruselli in Weligama seriously impacted consumption of fish by general public. This communication reports the findings of a short-term study on gut contents of H. quadrimaculatus , which was carried out to investigate the root cause of the people’s beliefs that Korumburuwa is poisonous.","PeriodicalId":21784,"journal":{"name":"Sri Lanka Journal of Aquatic Sciences","volume":"18 1","pages":"73"},"PeriodicalIF":0.0,"publicationDate":"2016-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72741336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Occurrence of bacteria species responsible for vibriosis in shrimp pond culture systems in Sri Lanka and assessment of the suitable control measures 斯里兰卡虾池养殖系统弧菌病病原菌种类的发生及适当控制措施的评估

Sri Lanka Journal of Aquatic Sciences Pub Date : 2016-02-20 DOI: 10.4038/SLJAS.V21I1.7481

P. Heenatigala, M. Fernando

{"title":"Occurrence of bacteria species responsible for vibriosis in shrimp pond culture systems in Sri Lanka and assessment of the suitable control measures","authors":"P. Heenatigala, M. Fernando","doi":"10.4038/SLJAS.V21I1.7481","DOIUrl":"https://doi.org/10.4038/SLJAS.V21I1.7481","url":null,"abstract":"Shrimp culture in Sri Lanka is continuously affected by bacterial infections and most symptoms agree with the disease called vibriosis. Therefore a bacteriological study was undertaken in shrimp farms to identify the diversity of pathogenic Vibrio species, favorable environmental conditions for them and sensitivity to antibiotics to control them. Water and infected animals from shrimp farms of the Western and North Western provinces were screened for Vibrio . Conventional methods were used for presumptive identification of isolated bacteria. Water quality was analyzed by spectophotometric methods. Disk diffusion technique was used to evaluate antibiotic sensitivity. During the study, 40 bacteria isolates belonging to the family Vibrionaceae were recorded. Of those, 24 isolates belonged to Vibrio species which are responsible for vibriosis in shrimps. Those were Vibrio alginolyticus , V. parahaemolyticus , V. damsela , and V. anguillarum . Most frequently isolated species was V. parahaemolyticus . All Vibrio isolates were found to be resistant to Ampicillin, Gentamycin, Oxytetracyclin, Chloramphenicol, Trimethoprim and Kanamicin, which are commonly used antibiotics in aquaculture. Water quality conditions indicated that the alkaline pH conditions and high salinity and ammonia levels favour the occurrence of high vibrio counts. Results indicate that the application of antibiotics for the control of vibriosis in shrimp farms has limited effectiveness due to the development of resistant bacterial strains and environmental management is the best management intervention that can be used to control this disease.","PeriodicalId":21784,"journal":{"name":"Sri Lanka Journal of Aquatic Sciences","volume":"183 1","pages":"1"},"PeriodicalIF":0.0,"publicationDate":"2016-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83030341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 39

The potential benefits of rainwater harvesting for households in the Jaffna Peninsula 雨水收集对贾夫纳半岛家庭的潜在好处

Sri Lanka Journal of Aquatic Sciences Pub Date : 2016-02-20 DOI: 10.4038/SLJAS.V21I1.7486

P. Rink, Christina Semasinghe, H. Manthrithilake

引用次数: 2

Toxic effects of Trebon, a synthetic pyrethroid based insecticide formulation, on Oreochromis mossambicus (Family: Cichlidae) 拟除虫菊酯类合成杀虫剂Trebon对凤蝶的毒性研究

Sri Lanka Journal of Aquatic Sciences Pub Date : 2016-02-20 DOI: 10.4038/SLJAS.V21I1.7484

W. Chandrasekara, K. Premarathna

{"title":"Toxic effects of Trebon, a synthetic pyrethroid based insecticide formulation, on Oreochromis mossambicus (Family: Cichlidae)","authors":"W. Chandrasekara, K. Premarathna","doi":"10.4038/SLJAS.V21I1.7484","DOIUrl":"https://doi.org/10.4038/SLJAS.V21I1.7484","url":null,"abstract":"Trebon ® (active ingredient: Etofenprox) is a recently developed potential pyrethroid insecticide formulation and reported to bring about adverse effects to non-targeted organisms in agricultural fields and associated habitats. The toxic effects of Trebon ® on fingerlings of tilapia (Oreochromis mossambicus) were studied in the present investigation following standard laboratory experimentation procedures. Results revealed that the 24-hr and 96-hr LC50 s of Trebon ® were 0.0657 mg L -1 and 0.0087 mg L -1 respectively which are nearly 23 times and 172 times below its recommended field dose which is 1.5 mg L -1 . It therefore appears that Trebon ® brings about mortality to tilapia fingerlings at concentrations that are milder than the field dose within a short period of exposure. Gill hyperplasia, deformation and telangiectasis of secondary gill lamella, mucosal cell proliferation, lamella disorganization and fusion were observed in the insecticide exposed test fishes. The liver tissues were also damaged with intracellular vacuolation, aggregation of melanomacrophages, blood congestion and focal necrosis. The severity of these damages increased with the level of dosage and the exposure period. The fingerlings suffered respiratory distress while the body coloration gradually changed into a pale hue upon exposure to Trebon ® .","PeriodicalId":21784,"journal":{"name":"Sri Lanka Journal of Aquatic Sciences","volume":"3 1","pages":"35"},"PeriodicalIF":0.0,"publicationDate":"2016-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72553203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Introduction of a bowser for the transportation of fish seed in Sri Lanka: Impacts and economics 斯里兰卡鱼籽运输船的引进:影响和经济

Sri Lanka Journal of Aquatic Sciences Pub Date : 2016-02-20 DOI: 10.4038/SLJAS.V21I1.7482

J. Chandrasoma, C. Pushpalatha

{"title":"Introduction of a bowser for the transportation of fish seed in Sri Lanka: Impacts and economics","authors":"J. Chandrasoma, C. Pushpalatha","doi":"10.4038/SLJAS.V21I1.7482","DOIUrl":"https://doi.org/10.4038/SLJAS.V21I1.7482","url":null,"abstract":"Under the Aquatic Resource Development and Quality Improvement Project (ARDQIP) of the Ministry of Fisheries and Aquatic Recourses of Sri Lanka, which was implemented during 2003-2010, a greater emphasis was laid on the development of culture-based fisheries (CBF) and activities aimed at enhancing fish seed production in the country. One of the foremost needs was to improve facilities for transport of fish seed to meet the envisaged increase in fish seed production and related stocking in remote areas. ARDQIP was instrumental in designing and introduction of a fish seed transport vehicle (bowser), and this mode of fish seed transport has become very popular in the country. At present, over 90% of fish seed transport is carried out using bowsers. Introduction of this bowser has made fish seed transport process easier, efficient and economical. The use of the bowser has prevented pollution due to non-necessity of using a large quantity of polythene for packing, making this practice environmentally friendly. Availability of fish seed transport bowsers facilitated enhanced stocking of water bodies and facilitated the development of CBF in Sri Lanka. Design and the features of the fish seed transport bowser are described in this paper together with discussion on its impact, advantages, disadvantages and economics.","PeriodicalId":21784,"journal":{"name":"Sri Lanka Journal of Aquatic Sciences","volume":"49 1","pages":"19"},"PeriodicalIF":0.0,"publicationDate":"2016-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80559875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0