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1.
Infections with EHV1 can lead to manifestation at the CNS of horses followed by encephalomyelitis and "equine stroke". Horse experiments could confirm the clinical picture and gave links to the potential pathogenesis of the disease. We also have been in the position to isolate and characterize an EHV4 virus out of the brain of a horse with CNS disorders. The two viruses carry different biological properties which obviously dominate the pathogenesis. These properties as well as experimental and field cases are described and different diagnostic tests are discussed. 相似文献
2.
斑点叉尾鮰病毒囊膜蛋白ORF6在昆虫细胞中的表达 总被引：2，自引：0，他引：2
为构建基于杆状病毒表达系统的CCV新型亚单位疫苗,将CCV的囊膜蛋白基因ORF6克隆至杆状病毒转座载体pFastBacTM 1质粒中,并将阳性重组转座质粒转化进含穿梭载体Bacmid的感受态细胞DH10Bac中,获得重组子rBacmid-ORF6。在脂质体介导下将该重组子转染sf9昆虫细胞,获得重组杆状病毒AC-ORF6。AC-ORF6感染的sf9昆虫细胞,经超薄切片电镜观察,可见重组杆状病毒呈多粒包埋,经间接免疫荧光、Western-blotting检测,CCV的ORF6蛋白可以在感染了AC-ORF6的sf9细胞中表达。研究表明,获得了插入ORF6基因的重组杆状病毒,并且该基因可以在重组杆状病毒介导下在昆虫细胞中表达,从而为基于CCV ORF6的杆状病毒亚单位疫苗研究奠定了基础。 相似文献
3.
The Federal Republic of Germany is at present free from Foot-and-Mouth Disease (FMD). In many countries of the world, however, FMD is still an enzootic disease. Therefore, countries free from FMD have to be constantly on guard against importing the disease. The plurality of the agent as well as ways of transfer of the disease are described. In particular, clinical signs and pathological injuries are described and illustrated by photographs. Methods of preparing specimens from infected animals for laboratory diagnosis are pointed out. 相似文献
4.
Abstract A detailed review of proliferative kidney disease (PKD) in salmonids is presented. The introduction places the disease in a historical context. The various aspects of the disease are described from the existing literature, together with latest findings from current research. Particular emphasis is given to epidemiology, aetiology and pathology. 相似文献
5.
W Kraft 《Tier?rztliche Praxis》1987,15(2):167-179
Neurological examination in equine practice, physiological findings and pathological disturbances are described. Because of the sizes of the horse the neurological examination is more difficult than in small animals. The examination of cerebrospinal fluid is a worthful completion and is able to refer to the etiology of a certain disease. The technique of the puncture of cerebrospinal fluid is described. 相似文献
6.
对虾免疫机能研究概况 总被引：16，自引：0，他引：16
Shrimp farming is an important source of revenue and employment in many developing countries.However, infectious diseases have adversely affected the profitability of shrimp industry. For this reason, disease prevention is a priority and shrimp immunology has become a crucial research area of this field. In this paper, the current importance and problems of shrimp-culture were described and the research advances in shrimp immunological defence mechanisms were summarized. The immunological tools are powerful and useful to evaluate the health state of the shrimp. The immunologies of shrimp mainly consist of cellular immunity and humoral immunity. In regard to cellular parameters, they are composed of haemocyte count (THC), differential haemocyte count (DHC) and reactive oxygen intermediates (ROIs). The immunity ceils exert their defence functions through phagocytizing, enveloping, etc, and the changes of THC and DHC are related to health state of shrimp. The ROIs generated during post phagocytic event which maybe an important marker to evaluate the immunological capability and phenoloxidase activity have been considered as a potential marker which is relevant to the health of the shrimp too. Concerning humoral parameters, prophenoloxidase (ProPO) and phenoloxidase,antimicrobial peptides and proteins, hemagglutinin and plasma proteins were described. The determining methods of immunity parameters were discussed. The response of shrimp to pathogens such as bacteria, virus, etc. and environmental factors such as DO, pH, etc, were also reviewed. It is well-known that the immune responses induced by immunizing crustacean or shrimp are mainly the non-specific immune responses. The potential of immunological parameters, including the changes of THC and DHC, the production of ROIs, phenoloxidase (PO) activity, antibacterial activity of plasma, and so on, to appraise the healthy state of shrimp were partly discussed. The future directions for the evaluation of the immunological capability of shrimp were proposed. 相似文献
7.
Abstract. During the exceptionally good summer of 1984, severe losses occurred at a number of marine salmon farms in the west of Ireland. Clinical signs and associated histopathology of the disease are described together with relevant meteorological data gathered during the course of the mortalities. The clinical, histopathological and meteorological data observed strongly suggest that prolonged exposure to solar ultraviolet radiation played a major role in the losses which occurred. Other contributory factors involved in the mortalities are described and discussed. 相似文献
8.
Abstract. An epizootic disease in redfin perch, Perca fluviatilis L., in north-east Victoria, Australia, was found to be caused by a recently described iridovirus. The acute disease is characterized by necrosis of the renal haematopoietic tissue, liver and spleen, with variable involvement of the pancreas. Transmission studies confirmed that the iridovirus is the causative agent of the disease. High mortalities occurred in 0+ juveniles in early summer and appear to be a recurrent seasonal event, whereas more sporadic outbreaks occurred in older age classes. Carrier fish were detected at low prevalence. The disease is described as epizootic haematopoietic necrosis (EHN) and is the only viral disease of fish known to occur in Australia. 相似文献
9.
Viral nervous necrosis (VNN) associated with mass mortalities in cage-reared sea bass,Dicentrarchus labrax (L.) 总被引：1，自引：0，他引：1
Mass mortalities of the European sea bass, Dicentrarchus labrax (L.), occurred in different ongrowing units in Greece. A presumptive diagnosis of viral nervous necrosis (VNN) was made on the basis of the light microscopic observations of a vacuolating encephalopathy and retinopathy. Positive peroxidase reaction with VNN antiserum confirmed nodavirus as the causative agent. Usually recorded in larvae and juvenile stages of different marine fish species, VNN is described in adult sea bass and sea bass reared in floating cages in the Mediterranean for the first time. The horizontal transmission of the disease has been strongly suspected. Histological analyses clearly demonstrate that cells other than nerve cells are also infected. Some epidemiological aspects of the disease are described and their implications for the establishment of prophylactic guidelines are discussed. 相似文献
10.
Eight juvenile cattle with symptoms of hyena disease are described. This represents the first occurrence of the condition in the Republic of Poland. The growth of the affected animals was retarded, with a marked difference in longitudinal growth of the femoral, humeral, tibial and metatarsal bones. The animals showed altered nickel, manganese and inorganic phosphate concentrations, which may be related to the disease. The genetic studies did not reveal any aetiological factors. 相似文献
11.
Stocking strategies 总被引：4，自引：0，他引：4
I.G. COWX 《Fisheries Management and Ecology》1994,1(1):15-30
Abstract Stocking, transfer and introduction of fish are commonly used to mitigate loss of stocks, enhance recreational or commercial catches, restore fisheries or to create new fisheries. However, many stocking programmes are carried out without definition of objectives or evaluation of the potential or actual success of the exercise. This paper describes a strategic approach to stocking aimed at maximizing the potential benefits. A protocol is discussed which reviews factors such as source of fish, stocking density, age and size of fish at stocking, timing of stocking and mechanism of stocking. The potential genetic, ecological and environmental impacts of stocking are described. 相似文献
12.
A rarely diagnosed case of urachal abscessation without any signs of inflammation of the extra-abdominal navel in a seven-month-old Braunvieh heifer is described. The symptoms of this disease, its diagnosis by the means of ultrasonographic examination and its therapy are explained. The technique of ultrasonographic examination is supposed to be a facilitation of presurgical diagnosis of umbilical disease. Nevertheless the value of this diagnostic procedure should be checked up on more patients. 相似文献
13.
Prawn diseases encountered by the authors during research programmes on prawn cultivation are described and discussed. A variety of seawater penaeid species, the freshwater caridean Macrobrachium rosenbergii, and the seawater caridean Palaemon serratus were affected. Poor husbandry, in terms of holding tank design, water quality and/or inadequate nutrition, is often the major factor precipitating prawn disease. Attention to husbandry techniques and the routine monitoring of water quality are of paramount importance in the prevention of disease outbreaks. The significance of disease to prawn cultivation, either as a direct cause of mortalities or as a limitation to market sale, is highlighted. 相似文献
14.
Abstract. A fungal infection of Atlantic salmon parr (0 +) occurring at low water temperatures, principally in January, is reported from fish farm hatcheries in western Scotland. Clinical signs and histopathology of the disease are described, illustrated, discussed and compared with those of certain other fungal diseases of salmonids. The fungus, provisionally placed in the hyphomycete genus Phialophora is described and illustrated from pure culture, with a discussion of its taxonomic position. 相似文献
15.
Duck plague: clinical aspects, diagnosis, control 总被引：1，自引：0，他引：1
M Weingarten 《Tier?rztliche Praxis》1989,17(1):53-56
A predominantly acute, highly contagious disease of the waterfowl is called duck plague or virus enteritis of ducks. The pathogenic agent is a herpes virus, type A. The clinical course of the disease and its pathological-anatomical findings are described and the possibility of prophylactic immunization is discussed. The results of lab trials demonstrate the effectiveness of a vaccine against the duck plague. 相似文献
16.
Dina A. Proestou Ryan J. Corbett Tal Ben‐Horin Jessica M. Small Standish K. Allen 《Aquaculture Research》2019,50(8):2142-2154
Perkinsus marinus, the causative agent of Dermo disease, is responsible for mass mortalities and negatively impacts aquaculture production of the eastern oyster, Crassostrea virginica. Selective breeding is a viable option for Dermo disease management; however, fluctuations in natural selection pressure and environmental noise hinder accumulation of genetic gains acquired through field performance trials. The purpose of this study was to adapt and apply laboratory disease challenge methods to eastern oysters, better characterize resistance‐specific traits and assess the potential for genetic variation in Dermo resistance among distinct families within a breeding population. Two challenge experiments were conducted, one in 2014 and the other in 2015. Significant treatment (control vs. challenged) and family effects on survival (measured as per cent survival and days to death) were detected in the 2014 challenge, while overall high survival precluded the detection of a significant family effect in the 2015 challenge. An alternate measure of resistance, parasite elimination rate, was also measured in the 2015 challenge, and this varied significantly among families. Thus, both survival and the change in parasite concentration in oyster tissues over time represent Dermo resistance phenotypes that can be measured accurately with the adapted laboratory disease challenge protocol described here. The obvious next step is to incorporate the challenge protocol in eastern oyster breeding programmes to assess whether well‐defined, accurately measured, Dermo‐resistant phenotypes result in enhanced genetic improvement for this commercially important trait. 相似文献
17.
O. M. AMIN 《Journal of fish diseases》1979,2(3):207-217
Abstract. Lymphocystis disease is reported from seven fish species in 48 of Wisconsin's 72 counties (67%). It was previously known from only two fish species in five counties. The record from northern pike, Esox Indus L. is new. Five other host records are new for Wisconsin. A relationship between the disease distribution in new waters and walleye, Stizostedion vitreum (Mitchill), stocking sources is noted. Histologlcal observations from black crappie, Pomoxis nigromaculatus (Lesueur) and walleye are similar to previously published accounts. Events in hyaline capsule degeneration are described for the first time. In Wisconsin, the disease was most commonly observed in the spring, particularly in walleye, but was consistently evident throughout the rest of the year. 相似文献
18.
The research facilities at the fish experimental station at Sunndalsöra are described. The design of a selection experiment with salmon and sea trout is presented. The station is also used for other purposes, such as investigations into nutrition, pathology and environmental factors.In this paper analyses of observed differences to vibrio disease (Vibrio anguillarum) are reported. Significant differences in resistance between river strains of salmon parr were found. The difference between localities are supposed to be partly heritable.The data were also used to estimate the heritability on an intra-river basis. The estimates were 0.12 and 0.07 based on the sire and dam component, respectively. It is concluded that selection against vibrio disease will result in genetic change. 相似文献
19.
Abstract. The histological features of the disease caused by infection of turbot by Herpesvirus scophthalmi are described. Infection of epidermal cells of skin and gill resulted in the formation of giant cells showing a variety of nuclear and cytoplasmic changes associated with the replication of the virus. The effects of the condition together with possible control measures are discussed. 相似文献
20.
Trials of a computer vision machine (The CatchMeter) for identifying and measuring different species of fish are described. The fish are transported along a conveyor underneath a digital camera. Image processing algorithms: determine the orientation of the fish utilising a moment-invariant method, identify whether the fish is a flatfish or roundfish with 100% accuracy, measure the length with a standard deviation of 1.2 mm and species with up to 99.8% sorting reliability for seven species of fish. The potential application of the system onboard both research and commercial ships is described. The machine can theoretically process up to 30,000 fish/h using a single conveyor based system. 相似文献