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Chương trình đào tạo nghề trình độ dưới 3 tháng – Kỹ thuật nuôi cá chạch lấu
Nội dung của tài liệu trình bày kỹ thuật nuôi cá chạch lấu: xây dựng, chuẩn bị ao nuôi; thả giống và chăm sóc, quản lý ao nuôi; phòng và trị bệnh.
3/30/2020 1:28:58 AM +00:00
DNA barcoding on cardinalfishes (Apogonidae) of Thoothukudi coast
Cardinalfishes belongs to the family, Apogonidae is cryptic in nature that often shows taxonomic ambiguity through conventional taxonomy. It is globally accepted that mitochondrial DNA marker i.e., Cytochrome C Oxidase (COI) can be used to resolve these taxonomic uncertainties. In the present study, the DNA barcode was developed using COI marker for the two species of cardinalfishes (Archamia bleekeri and Ostorhinchus fleurieu) collected from Thoothukudi coast. Results showed that the distance values between the two species are higher than that of within the species. The Cytochrome C Oxidase subunit I (COI) gene showed more number of transitional pairs (Si) than transversional pairs (Sv) with a ratio of 2.4. The average distance values between A. bleekeri and O. fleurieu were 3.825, 4.704, 5.145, 7.390, 8.148, 7.187 and distance values among the A. bleekeri and O. fleurieu were 4.777 and 3.660, 3.583 and 6.509 respectively using K2P parameter. The average nucleotide frequency calculated were A= 26.9%, T(U)= 24.3%, C= 21.95% and G= 26.8%. The estimated GC content of A. bleekeri and O. fleurieu was (49.9%) and (47.6%) respectively and the average GC content was found to be 48.75%. Phylogenic trees were constructed individually for the two species using MEGA 6.0 software and the Neighbour-Joining tree showed distinct clusters shared by the species of same genera. In conclusion, the present study developed DNA barcode database for the two species of cardinal fishes that can be used for taxonomic purposes for these species.
3/30/2020 1:20:15 AM +00:00
Research on climate change and fisheries: A scientometric analysis
Climate change has become one of the most contentious as well as pressing issue of our times. Changes and variations in rainfall pattern and temperature have already begun to adversely affect capture and culture fish production. The impactful scientific literature produced on climate change in relation to fisheries was tracked for period since 1990 till 2018. The open source freeware Publish or Perish (PoP) desktop application was used to retrieve the scientific articles, which were then subjected to scientometric study. Several relevant word combinations of ‘climate change’, ‘fisheries’, ‘aquaculture’, ‘fish’, and ‘aquatic environment’ were used as search terms in PoP. After repeated screening, a total of 1,221 articles on climate change and fisheries were collated and then subjected to descriptive statistical analysis using MS-Excel and the data visualization software Power Bi. The results showed that output of scientific literature on ‘climate change and fisheries’ significantly increased after 2005. The five journals Journal of Coastal Research, Natural Hazards, Ocean and Coastal Management, Journal of Coastal Conservation and Sustainability Science were the top most preferred journals by authors for publishing ‘climate change in fisheries’ related studies. The 3 most impactful articles on ‘climate change in fisheries’ were authored by EH Allison, WWL Cheung and JM Roessig who were affiliated to institutions in USA and Canada. One third of the publications had single authors while 21% had two authors. In India, E. Vivekanandan (7; CMFRI), R.S. Mahendra (6; INCOIS) and A. S. Rajawat (SAC) are the ones with most publications. Climate science in India is still at nascent stage and increased funding and attention would be essential to evolve evidence based climate change adaptation strategies.
3/30/2020 1:07:12 AM +00:00
Trend analysis of inland fish production of Tamil nadu with special references to resources and seed production
Inland fishery resources are significantly contributed in fisheries sectors. In this regard, trend of inland fish production of Tamil Nadu was analyzed based on the available resources and utilization and seed production for the last decade. Calculated Average Annual Growth rate of fish seed production and inland fish production were 10.21% and 1.85%, respectively. The linear regression line for inland fish production was indicated that increasing trend for every year (R² = 0.673), while fish seed production was negative trend (R² = 0.094). Also, the positive relationship was existed between fish seed production and inland fish production of Tamil Nadu, which was proved by R² = 0.503. In this regard, Tamil Nadu also has vast inland fishery resources (3.83 lakhs ha.) in the form of ponds, tanks, river, reservoirs and brackish water with potential of the state is 4.5 lakhs tons but the present fish production was 2.15 lakhs tons only (2016-17) due to 46.67% of potential resources were underutilized condition. Moreover, it has significant open water and inland farming resources were 87% and 13%, respectively with the inland fish production of 70.7% and 29.3% respectively, which proved that open water resources were highly contributed in inland fish production, even if considerable areas were underutilized condition while comparing to inland farming area. The study recommends that proper utilization of natural resources may increase the inland fish production of the state.
3/30/2020 1:07:06 AM +00:00
Quality assessment and comparison of three different types of fish retail outlets of Navi mumbai, Maharashtra, India
In India, fish consumers prefer three types of retail markets viz., local dry fish market, local fresh fish market and supermarket wherein no stringent food safety measures are followed and monitored. Hence, the present study was planned to analyze food safety parameters for different outlets by collecting equal numbers of fish samples from all three markets of Navi Mumbai region. Proximate composition, biochemical and microbiological parameters were evaluated. Antibiogram for the isolated Staphylococcus aureus and Escherichia coli from these fishes was studied. In dry fish market, most of the fish had higher total volatile basic nitrogen (TVB-N) and formaldehyde than permissible level. In present evaluation, formaldehyde content of fishes from different markets exhibited a higher percentage (1.03-1.93 mg%) than the recommended value. Local retail fresh fish market samples had higher levels of Aerobic Plate Count (APC), E. coli and S. aureus. One sample from dried fish market exceeded the permissible limit of APC (2,36,000 cfu/g). Supermarket samples contained all the microbial and biochemical levels within the limit but exhibited higher formaldehyde content. Multiple drug resistant bacteria also existed in both local and supermarket samples. Monitoring authorities of India need to monitor the quality of fish in different markets at regular interval and strict action may be taken for seafood safety.
3/30/2020 1:04:15 AM +00:00
Comparative performance of serial collapsible fish trap using different funnel designs
The effectiveness of four different funnels such as Rectangular, Oval, heartin and Circular shaped funnels were tested in a serial collapsible fish trap through fishing trials conducted in a coastal fishing ground of Mandapam of Tamil Nadu, India. A total of 24 fishing operations were carried out.
3/30/2020 1:03:08 AM +00:00
Role of gene expression techniques in fisheries and aquaculture
The exploited wild stocks should be confessed to biodiversity and genomic study to find out genetic variation and identification of fish stocks with reference to morphological, biological and physiological traits. Transcription reveals that transfer of DNA to mRNA. Translation exposes that transfer of mRNA to protein. These genetic changes can be assessed by several gene expression techniques which pave to identify the particular organisms upto species level which helps to find out native/exotic species abundance.
3/30/2020 12:53:47 AM +00:00
Indian almond tree (Terminalia catappa Linn.) as herbal biomedicine in aquaculture industry
Aquaculture is growing drastically over the years with intensification. On the other hand intensification increased the stress, occurrence of diseases, introduction of new pathogens and application of the synthetic chemical substances to overcome these problems. Recently adoption of herbal medicine in aquaculture practices is becoming the trend due its advantages over the chemical substances. Plants are storehouses and sources of safer and cheaper chemicals. Numerous herbal plants have been identified for its anti-microbial, antifungal, anti-parasitic, growth promotion, appetite stimulation, immunostimulation and stress reducer properties. Indian almond tree (Terminalia catappa Linn.) is one among them. Tannin is the major chemical component of T. catappa which exhibits the antimicrobial property. The reports on use of Indian almond leaves as herbal biomedicine have been reviewed in the present article. The extensive work need to be done to optimize the dose and duration of treatment against the most common pathogens.
3/30/2020 12:52:46 AM +00:00
A way forward in aquariculture/ornamental fish farming
Aquariculture is the one among fast growing industries. There is huge demand for the endemic ornamental fishes in the international market. Due to unsustainable exploitation, valued native decorative fishes are in the state of endangered and extinction. Development of captive breeding technology could be possible way of conservation fishes without affecting the growth of aquariculture sector.
3/30/2020 12:52:40 AM +00:00
A study on the socio-personal profile of the farmers practicing integrated fish farming of Manipur, India
The present study was conducted with an objective to analyses the socio-personal profile of farmers practicing integrated-fish-farming of Manipur. This study was conducted on 300 farmers in 15 villages viz. Takcham, Tentha, Athokpam, Lameidong, Wabagai, Hiyanglam, Khabi Bomdiar, Wangoi, Uchiwa, Leimapokpam, Irengbam, Maibam, Naharup, Heyanglam, and Top. These 15 villages were selected from 5 districts viz. Thoubal, Kakching, Imphal West, Bishnupur and Imphal East district, respectively. It was aimed to analyses the Socio-personal profile of the farmers practicing the integrated-fishfarming. The study was undertaken from March 2017 to October 2018 and the data pertain of the year 2017 and 2018. In the present study, data was generated through a sample survey of farmers by personal interview method using pretested well-structured interview schedule. Random sampling was adopted for the selection of the respondents. From the study it is obtain that the farmer engages in integrated fish farming farmers have the following parameters with majority of age group show 36-60 year (53.33%), married (96.67%), OBC (66.67%), High School (27.67%), Joint family type (71.33), Family size above 5 (73.33), IFF as sole profession(48%), member of an organization (47.67%). The study concluded that understanding of socio-personal characteristics of the farmer practicing integrated fish farming can hold the extension agents to formulate various training design to target the specific level of farmers.
3/30/2020 12:51:22 AM +00:00
Bài giảng kỹ thuật nuôi Cá bông lau trong ao đất
Nội dung của bài giảng trình bày thông tin về cá bông lau; môi trường sống của cá bông lau; kỹ thuật nuôi các bông lau trong ao đất; cải tạo ao; thả giống; thức ăn; cách cho ăn; chăm sóc và quản lý.
3/30/2020 12:47:23 AM +00:00
Bài giảng Kỹ thuật nuôi cua biển: Cua xanh Scylla serrata (Forskal)
Nội dung của bài giảng trình bày đặc điểm hình thái của cua; đặc điểm sinh học của cua; các hình thức nuôi chủ yếu; cách chăm sóc cua. Để nắm chi tiết nội dung kiến thức mời các bạn cùng tham khảo bài giảng.
3/30/2020 12:47:17 AM +00:00
Phân loại cá bỗng (Spinibarbus) ở một số tỉnh miền núi phía Bắc Việt Nam dựa trên đặc điểm hình thái
Nghiên cứu này được tiến hành trên 50 mẫu cá Bỗng. Các mẫu cá Bỗng trong nghiên cứu được thu từ sông, suối ở các tỉnh: Sơn La, Hòa Bình, Tuyên Quang, Hà Giang và Lạng Sơn.
3/29/2020 9:25:32 PM +00:00
Xác định tính chất nhiệt vật lý và thời gian cấp đông mực ống (Loligo chinensis) bằng phương pháp giải tích
Bài viết này trình bày một mô hình giải tích đơn giản để tính toán tính chất nhiệt vật lý và thời gian cấp đông mực ống bằng hai biên đối lưu không đối xứng. Mô hình này dựa vào phương trình cân bằng nhiệt tức thời của vật cho các giai đoạn chuyển pha với quá trình truyền nhiệt không ổn định trong giai đoạn làm lạnh, chuyển pha và quá lạnh.
3/29/2020 9:22:28 PM +00:00
Phân lập và xác định một số đặc điểm sinh học các chủng Streptococus agalactiae gây bệnh trên cá rô phi đỏ (Oreochromis sp.) nuôi tại Thừa Thiên Huế
Streptococcus agalactiae là một trong những tác nhân chính gây bệnh trên cá diêu hồng hay rô phi đỏ (Oreochromis sp.) nuôi trên thế giới. Nghiên cứu này đã phân lập được 27 chủng cầu khuẩn Streptococus trên cá rô phi bị bệnh nuôi tại thị xã Hương Trà và Hương Thủy, tỉnh Thừa Thiên Huế.
3/29/2020 9:22:22 PM +00:00
Ảnh hưởng của Supastock lên thành phần và mật độ thức ăn tự nhiên trong ao ương tôm Post - larvae tại khu vực Thừa Thiên Huế
Nghiên cứu được thực hiện nhằm đánh giá ảnh hưởng của chế phẩm Supastock lên thành phần và mật độ thức ăn tự nhiên trong ao ương tôm thẻ chân trắng. Sáu ao nuôi được bố trí ngẫu nhiên vào 2 nghiệm thức: (A) bổ sung chế phẩm Supastock 2 ngày 1 lần và (B) đối chứng, không bổ sung. Ao được lót bạt và mỗi ao có diện tích 2.000 m2 /ao, và mật độ nuôi là 500 con/m2 .
3/29/2020 9:21:49 PM +00:00
Dự đoán nhanh hạn sử dụng của fillet cá tra lạnh đông bằng phương pháp mô hình toán học
Trong nghiên cứu này, phương pháp mô hình toán học được sử dụng để dự đoán nhanh hạn sử dụng của fillet cá tra lạnh đông. Cá tra tươi sau khi mua về tiến hành fillet, rửa sạch, cho vào các túi nilon, kéo zip, để lạnh đông ở -25 °C trong vòng 6 giờ, sau đó bảo quản ở 3 mức nhiệt độ -3, -8, -13°C để theo dõi sự hư hỏng của sản phẩm thông qua việc đo mức độ oxy hóa chất béo và phần trăm khối lượng sụt giảm của sản phẩm theo chu kỳ 7 ngày/lần.
3/29/2020 9:21:37 PM +00:00
Loại bỏ phi collagen trên da cá ngừ vây vàng bằng dung dịch NaOH
Da cá ngừ vây vàng (Thunnus albacares) được lấy từ quy trình chế biến cá ngừ fillet đông lạnh làm nguyên liệu để sản xuất collagen. Để tách chiết collagen từ da cá thì việc loại bỏ phần phi collagen là rất quan trọng.
3/29/2020 9:20:14 PM +00:00
New dimension in fish immunotherapeutics: Avian egg yolk antibody (IgY)
Intensification in aquaculture practices has resulted the development of various diseases caused due to pathogens and water quality issues. In recent times, the usage of antibiotics for controlling bacterial diseases in aquaculture has been proven unsustainable and barren due to development of antibiotic resistance in pathogens one of the greatest human health challenges of the 21st century. Many measures have been used as potential alternatives to antibiotics including organic and inorganic acids, antibodies, probiotics and herbal products. Oral administration of Immunoglobulin (IgY) has attracted significant attention worldwide as a means of controlling infectious diseases of bacterial and viral origin in fishes due to its high specificity. In the present review, a holistic approach was studied to summarize the mode of action of IgY, advantage and application of IgY in aquatic organisms.
3/29/2020 8:44:20 PM +00:00
Feeding of different categories of fish, their nutritional requirements and implication of various techniques in fish culture – A review
Aqua cultural production is a major industry in many countries, and it will continue to grow as the demand for fisheries products increases and the supply from natural sources decreases. Good nutrition in animal production systems is essential to economical production of a healthy, high-quality product. In fish farming (aquaculture), nutrition is critical because feed typically represents approximately 50 percent of the variable production cost. Fish nutrition has advanced dramatically in recent years with the development of new, balanced commercial diets that promote optimal fish growth and health. The development of new species-specific diet formulations supports the aquaculture industry as it expands to satisfy increasing demand for affordable, safe, high-quality fish and seafood products. Article provides a general overview of the wide variety of nanomaterials and technologies in fish culture that offer significant promising role for water recovery.
3/29/2020 7:38:24 PM +00:00
A study on fish marketing system in Himmatnagar, Sabarkantha, Gujarat
The study was conducted at fish markets in Himmatnagar, Sabarkantaha, and attempts study present marketing system, marketing activity and economic features. This paper to identify market facilities, present market status, nature of cost and the factor influence the market system. In Himmatnagar nearly all fish traded within move through the privet sector, a large number of people are give and take fish distribution and marketing system. The main source of fishes in Himmatnagar fish market is Dharoi dam, lake, small rivers and reservoir which supply various verities of fishes. Virtually most of fish near about 30% is locally supplied, near about 70% of fish are transfer to Ahemdabad. The freshwater fishes and marine fish are available near about 80% and 20% respectively. Major available fish’s species in Himmatnagar market are Indian major carp, exotic carp, cat fishes, hilsa, pomfret and shrimps.
3/29/2020 7:30:07 PM +00:00
Distribution of body energy in Etroplus suratensis (Bloch)
The present study was carried out to find out the distribution energy pattern in the body parts of Etroplus suratensis (bloch). The study indicated that the mean energy density of the edible portion of immature fish was 17.47 kJ/g dry weight compared 20.20 kJ/g and 19.65 kJ/g of adult female and male respectively. Similarly the energy density of inedible portion of immature fish was 15.65 kJ/g while that of adult female and male were 17.49 kJ/g and 16.62 kJ/gdry weight respectively.
3/29/2020 7:29:49 PM +00:00
Running mortality syndrome (RMS)- A new disease that struck the Indian shrimp industry
Infectious diseases are quiet common in shrimp culture operations. Apart from infectious diseases certain syndromes affecting the culture operations in the shrimp farms particularly from Andhra Pradesh and Tamil Nadu. Running mortality syndrome is such type syndrome associated with morbidity and mortality which leads to less productivity. In the present study we have examined the haemolymph and hepatopacreas of the infected shrimps. The results revealed that, the affected shrimp showed the higher percentage of Vibrio species such as Vibrio parahaemolyticus and Vibrio azureus. Histopathological studies also revealed that, high B cells in the hepatopancreas in the early stage of disease indicate the over feeding of shrimps. Running Mortality Syndrome is depicted be pond management associated syndrome rather than infectious in nature and thus can be overcome through best management practices.
3/29/2020 7:26:24 PM +00:00
Constraints in production, consumption and marketing of fish in selected districts of North Karnataka, India
The present study was carried out in Dharwad and Belagavi districts of North Karnataka to study the constraints in production, consumption and marketing of fish. For this purpose, multistage random sampling procedure was adopted for the selection of the ultimate unit of samples. The data was collected from 60 selected fish farmers, 60 selected fish consumers and 30 market functionaries during the period 2018-19. Garrett’s ranking technique was used to analyze the data. The results revealed that the lack of training facility, non-availability of quality fingerlings, water scarcity is some of the problems faced by the farmers in fish production. Market distances, price variation, non-availability of fresh fish were the major problems faced by the consumers of fish. Stiff competition, high bargaining, non-availability of proper storage facility are the major problems faced by the market functionaries in marketing of fish in the study area.
3/29/2020 7:22:59 PM +00:00
Growth, yield attributes and yield of pearl millet as influenced by phosphorus management practices in Kharif pearl millet
A field experiment was conducted during kharif seasons of 2017 and 2018 at Agricultural College Farm, Bapatla to evaluate the effect of phosphorus management practices on growth, yield attributes and yield of pearl millet. The seven treatments consisted of T1: No P, T2: 50% RDP T3: 75 % RDP, T4: 100 % RDP, T5: 50 % RDP + seed inoculation with PSB, T6:75 % RDP + seed inoculation with PSB, T7: 100 % RDP + seed inoculation with PSB with RBD design. The results showed that significantly the highest growth (plant height and drymatter production), yield attributes (earhead length and productive tillers per m -2 ), grain yield (kg ha-1 ) and stover yields (kg ha-1) were recorded with application of 100 % RDP + seed inoculation with PSB but remained statistically on par with the treatment which received 100 % RDP during both years of experimentation and in pooled data. Test weight (g per 1000 seeds) and harvest index were not significantly influenced by different treatments.
3/29/2020 7:06:26 PM +00:00
Risk and uncertainty analysis for shrimp trade in India using value at risk
India seafood exports achieved an all-time high of 11,34,948 MT and US $ 5.78 billion during 2016-17 with shrimp as the major commodity constituting about 39 percent by quantity and 67 percent by value. India also becomes one of the top shrimp exporting country in the world being USA and Japan be the major markets and followed by South east Asia, European countries, China, Middle east, etc. but there is high risk and uncertainty in shrimp trade due to trade barriers, exchange rates, high competition among shrimp producing countries. In this paper, we estimate value at risk and tried to identified more risk pron markets between the two major markets i.e. USA and Japan markets.
3/29/2020 7:02:55 PM +00:00
Prevalence of diseases caused by white spot virus and Enterocytozoon hepatopenaei in Penaeus vannamei shrimp farms in Nagapattinam District, Tamil Nadu, India
Disease is one of the major factors affecting the development and sustainability of aquaculture. White spot disease caused by white spot syndrome virus (WSSV) results in severe production and economic losses to the shrimp farming industry worldwide. Recently, Hepatopancreatic microsporidiosis caused by Enterocytozoon hepatopenaei (EHP) a microsporidian parasite has been reported to cause severe growth retardation and losses in commercial Penaeus vannamei farming. In the present study, we report the prevalence of white spot syndrome virus and hepatopancreatic microsporidiosis in the P. vannamei shrimp farms in Nagapattinam district, Tamil Nadu, India. This study was undertaken in a total number of 57 selected P. vannamei farms in Nagapattinam district, Tamil Nadu during the period from October 2016 to September 2017. P. vannamei samples collected at fortnight intervals were screened for WSSV and EHP by PCR. The results showed that the prevalence of diseases caused by WSSV and EHP were 49.12% and 66.66% respectively. This report alerts the farmers for the adoption of better management practices to be followed so as to prevent these diseases and improve the production and sustainability in P. vannamei farming.
3/29/2020 6:59:55 PM +00:00
Biochemical and microbiological quality of cultured shrimp litopenaeus vannamei of different farms of Ratnagiri
Shrimp aquaculture has become an economically important one and production has decreased in recent years due to the spread of infectious diseases, mostly that caused by bacterial infection. The shrimp are affected by the toxic substances which eventually enter in to their systems and bring about external damages. This study explores, it was aimed to assessment of the physiochemical and microbiological quality of different farmed shrimp from Ratnagiri. The results of this attempt for the study such as sensory, physicochemical, proximate composition and microbiological quality of shrimp Litopenaeus vannamei cultured in three different farms of Ratnagiri were compared. Fresh shrimps were analyzed for sensory attributes where, natural and bright colour, excellent odour, elastic and rigid texture with very good appearance was observed. The highest protein content (17.6%) was observed in samples collected from Varavde farm and lowest (16.8%) was observed in the samples collected from Ranpar farm. The highest fat content was found in the samples collected from Nevre farm i.e. 1.5% and lowest was found in the samples collected from Ranpar farm i.e. 1.3%. The highest moisture content was recorded in the samples of Ranpar farm i.e. 77.9% and lowest was recorded in the samples of Varavde farm i.e. 73.2%. The highest and lowest ash content was observed in the sample collected from Ranpar farm i.e. 1.9% and 1.4% respectively. The carbohydrate content was higher in the samples (2.4%) collected from Varavde farm and lowest in the samples of Nevre farm (1.5%).
3/29/2020 6:55:25 PM +00:00
Cơ sở khoa học của việc quản lý tổng hợp dải ven biển tỉnh Thừa Thiên Huế theo chức năng môi trường
Dải ven biển tỉnh Thừa Thiên Huế là dải ven biển có nhiều tiềm năng lớn để phát triển. Tuy nhiên hiện nay dải ven biển tỉnh Thừa Thiên Huế đang đối mặt với nhiều thách thức về nguồn tài nguyên và môi trường.
3/29/2020 5:46:42 PM +00:00
Nghiên cứu ảnh hưởng của thức ăn và độ mặn đến tỷ lệ thành thục của cá bống tro (Bathygobius fuscus ruppell, 1830)
Nghiên cứu ảnh hưởng của thức ăn và độ mặn đến tỷ lệ thành thục của cá bống tro (Bathygobius fuscus, Ruppell 1830) được tiến hành tại trại sản xuất giống và nuôi trồng thủy sản Ngọc Sơn, Đồ Sơn, Hải Phòng. Cá bố mẹ được tập hợp từ tự nhiên.
3/29/2020 5:44:46 PM +00:00