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1.
Parvovirus infection of Muscovy ducks caused by a genetically and antigenically distinct virus has been reported from Germany, France, Israel, Hungary, some Asian countries and the USA. The pathological changes include those of degenerative skeletal muscle myopathy and myocarditis, hepatitis, sciatic neuritis and polioencephalomyelitis. In the study presented here, day-old and 3-week-old goslings and Muscovy ducks were infected experimentally with three different parvovirus strains (isolates of D-216/4 from the classical form of Derzsy's disease, D-190/3 from the enteric form of Derzsy's disease, and strain FM from the parvovirus disease of Muscovy ducks). All three parvovirus strains caused severe disease in both day-old and 3-week-old Muscovy ducks but in the goslings only the two strains of goose origin (D-216/4 and D-190/3) caused disease with high (90-100%) mortality when infection was performed at day old. Strain FM (of Muscovy duck origin) did not cause any clinical signs or pathological lesions in the goslings. In the day-old goslings and Muscovy ducks the principal pathological lesions were severe enteritis with necrosis of the epithelial cells (enterocytes) of the mucous membrane and the crypts of Lieberkühn, and the formation of intranuclear inclusion bodies. Other prominent lesions included hepatitis and atrophy (lymphocyte depletion) of the lymphoid organs (bursa of Fabricius, thymus, spleen). In goslings infected with the strain originating from the classical form of Derzsy's disease mild myocarditis was also detected. After infection at three weeks of age, growth retardation, feathering disorders, myocardial lesions (degeneration of cardiac muscle cells, lympho-histiocytic infiltration) and hepatitis were the most prominent lesions in both geese and Muscovy ducks. In addition to the lesions observed in the geese, muscle fibre degeneration, mild sciatic neuritis and polioencephalomyelitis were also observed in the Muscovy ducks infected with any of the three parvovirus strains.  相似文献   

2.
A serological study of canine parvovirus (CPV) infections in a colony of dogs was conducted over a period of 8 months. Twenty-two of 24 adult dogs sampled initially had significant antibody titres to CPV. Nine litters of puppies wer e bled at fortnightly intervals and the sera tested for antibodies to CPV. Twenty-nine of 35 natural CPV infections observed were subclinical. A puppy in one litter developed vomiting and diarrhoea during the same period as seroconversion to CPV. Four puppies from a further litter developed histologically confirmed myocarditis. Serological testing of this latter litter indicated that the virus infections occurred between 2 weeks prior to and 1 week post whelping, and that clinical disease developed 20–40 days after viral infection. The mean half life of the decline of passively derived immunity to CPV was 8.3 days.  相似文献   

3.
The myocardial lesions of pigs (age from 2.5 to 3.5 month) with encephalomyocarditis virus infection are presented. The disease is caused by members of the genus Cardiovirus (family Picornaviridae). In Greece it was first observed 1987 in two stables of pig-breeders with a mortality of 80%. The macroscopic changes are characterized by a myocardial degeneration with greyish pale linear or round foci and by an accumulation of a clear red to yellow fluid in the pericardium and the pleural cavity. The most important histologic changes of the hearts are a diffuse or focal myocarditis with a severe infiltration of histiocytes, lymphocytes and plasma cells. Furthermore, degeneration and necrosis of cardiac muscle cells are observed. Electron microscopic investigations of the myocardial cells reveal mild mitochondrial edema, severe perinuclear and intranuclear edema, myelin figures, intra cisternal sequestrations of the rough endoplasmic reticulum, disorganization of the myofibrillar Z-line, and crystalloid viral structures between the mitochondria. Polyribosomes and accumulations of viral particles are frequently found in membrane bound cysts within myocardial cells and the capillaries. Furthermore, viral particles (single or in cysts) and crystalloid viral structures are observed in the cytoplasm of edematous endothelial cells.  相似文献   

4.
Sudden death of pups in the 4- to 6-week age range has recently been occurring in western Canada as a result of severe, primary, nonsuppurative myocarditis. At necropsy, the prominent macroscopic lesion was pulmonary edema, and microscopically, characteristic intranuclear inclusion bodies were found within cardiac myofibers in association with myocarditis. Ultrastructurally, numerous small particles resembling parvoviruses were found within the intranuclear inclusion bodies, which were positive by direct fluorescent antibody test for canine parvovirus. Of three pups inoculated with homogenate from affected myocardium, one developed lesions resembling canine parvoviral enteritis.  相似文献   

5.
BACKGROUND: Blastomycosis is a common systemic fungal infection in dogs. HYPOTHESIS: Dogs with cardiovascular involvement may have abnormalities in electrical conduction and valvular function, and may have a worse prognosis. ANIMALS: Eight client-owned animals. METHODS: Dogs with cardiovascular lesions caused by blastomycosis were identified from retrospective evaluation of medical records. RESULTS: Five dogs had de novo infections and 3 had recurrences of previously treated infections. Harsh labored breathing, lethargy, and anorexia were the most common historic complaints. Three dogs had syncope. Physical examination and clinicopathologic data were typical of blastomycosis and included dyspnea, increased lung sounds, and lethargy. In addition, 3 dogs had heart murmurs and 1 had a third-degree atrioventricular block. Four dogs had myocarditis and 2 had pericarditis or epicarditis. Two dogs had cardiac signs attributed to extracardiac compression by fungal granulomas and clinical signs were relieved by treatment. Half of the remaining 6 dogs were euthanized; 2 of these were not treated. Of the remaining 3 dogs, 1 dog died acutely while sleeping; the second died intraoperatively during an attempt to place an epicardial pacemaker; and the third had Blastomyces-induced endocarditis and died of heart failure. CONCLUSIONS AND CLINICAL IMPORTANCE: Blastomycosis should be considered in the differential diagnosis of dogs from endemic areas with inflammatory myocarditis, heart block, heart base or intracardiac mass lesions, syncope, or endocarditis.  相似文献   

6.
A blue-naped mousebird (Urocolius macrourus) was diagnosed by gross necropsy and histopathology as having a chronic, fibrosing bacterial cholecystitis. Acute, severe, necrotizing pneumonia and myocarditis also were present with intralesional gram-negative bacteria. The bacteria within the lungs and heart were suspected to have spread from the biliary tract because of the pattern of distribution and similar gram-staining characteristics. Enterobacter sp. and Escherichia coli were cultured from the pulmonary lesions. Cloacal cultures in clinically normal blue-naped mousebirds and speckled mousebirds (Colius striatus) yielded both Enterobacter sp. and E. coli. We hypothesize a pathogenesis in this bird consisting of biliary stasis of unknown etiology and eventual infection of the biliary tract by the normal gram-negative gastrointestinal flora. Death was believed to be a result of cardiac and respiratory dysfunction secondary to the bacterial dissemination from the biliary tree and endotoxemia.  相似文献   

7.
The first reported outbreak of bovine viral diarrhea (BVD) in 1946 described a transmissible acute disease characterized by severe leukopenia, high fever, gastrointestinal erosions and hemorrhages. However, in the ensuing years, the most commonly observed acute form of BVD was clinically mild. There was limited viral shed and spread following these acute infections. This led to the assumptions that acute infections with BVD viruses (BVDV) were clinically unimportant, spread of the virus within a group was always due to the presence of a persistently infected animal and transmission between healthy immunocompetent cattle was insignificant. These assumptions were challenged when outbreaks of severe acute BVDV were observed in North America starting in the late 1980s. This study demonstrates that widespread outbreaks of severe acute BVD observed in 1993 in North America can be traced to a single strain of BVDV that apparently spread explosively following acute infection. These findings are notable in that they draw into question management of acute BVD infection, design of studies examining virulence and nomenclature used to identify strains for GenBank submission.  相似文献   

8.
The pathologic and peroxidase immunohistochemical features of West Nile flavivirus (WNV) infection were compared in four horses from the northeastern United States and six horses from central Italy. In all 10 animals, there were mild to severe polioencephalomyelitis with small T lymphocyte and lesser macrophage perivascular infiltrate, multifocal glial nodules, neutrophils, and occasional neuronophagia. Perivascular hemorrhages, also noted macroscopically in two animals, were observed in 50% of the horses. In the four American horses, lesions extended from the basal nuclei through the brain stem and to the sacral spinal cord and were more severe than the lesions observed in the six Italian horses, which had moderate to severe lesions mainly in the thoracolumbar spinal cord and mild rhombencephalic lesions. WNV antigen was scant and was identified within the cytoplasm of a few neurons, fibers, glial cells, and macrophages. WNV infection in horses is characterized by lesions with little associated antigen when compared with WNV infection in birds and some fatal human infections and with other important viral encephalitides of horses, such as alphavirus infections and rabies.  相似文献   

9.
Third degree atrioventricular (AV) block in dogs is thought to be most frequently characterized by non-specific fibrotic changes in the AV node. However, it may occur secondary to an undiagnosed inflammatory process. We report a case of third degree AV block in a dog, secondary to acute lymphocytic-plasmacytic myocarditis that resulted in sudden death. This dog had cardiac troponin I levels of 44.65 ng/mL (normal <0.11 ng/mL). The serum cardiac troponin I level was five times higher than any other AV block patient measured in our laboratory, and was also substantially higher than in dogs with chronic valve disease or dilated cardiomyopathy. The severe myocardial necrosis observed at necropsy correlated with the degree of cardiac troponin I elevation. This report suggests that measurement of cardiac troponin I may be an indicated test before pacemaker implantation in dogs with third degree AV block.  相似文献   

10.
The pathogenesis of encephalomyocarditis (EMC) due to the EMC virus (EMCV) was studied in 24 piglets oro-nasally infected with the field isolate B279/95. Two pigs were kept as negative controls and were euthanised at hour 0. The remaining 24 were euthanised every 6 h up to 78-h post infection (hpi). Virus isolation, histological examination and EMCV immunodetection were performed on the spleen, intestine, pancreas, liver, kidneys, heart, lungs, lymph nodes, tonsils and brain. EMCV was isolated at 6-hpi from the intestine and lymph nodes and at 12-hpi from the heart. From 6 to 12-hpi, scattered degenerate myocardiocytes were immunolabelled. Subsequently, myocarditis developed and progressively worsened. Immunopositive reaction in tonsil macrophages, observed in the early stage of infection (6-hpi), suggests that tonsils are the portal of entry, and by mean of wandering macrophages the EMC virus is then distributed through the body. Afterwards, EMCV-B279/95 replicates intensively in the cytoplasm of myocardiocytes and the acute myocarditis is strictly related to the tropism of these cells. Four pigs died spontaneously. In three animals no post mortem lesions or virus were isolated/detected, although all of them showed mild myocarditis. The experimental infection with EMCV B279/95 indicates: (i) the experimental protocol mimics the individual variability observed in natural disease, (ii) tonsils are the portal of entry of infection and the heart is the target organ, (iii) EMCV provides a valuable animal model for comparative studies on progressive viral myocarditis.  相似文献   

11.
In two calves with massive cysticercosis and one healthy control calf the method of electrocardiographic examination was applied to a preciser determination of the clinical finding. The examination was performed on the 75th day after the experimental infection. Singly recorded electrocardiographic findings provided no characteristic symptoms indicating an injury of the conductive system of the heart. However, in both infected calves a lowering of the pulse frequency was found and in one of them also a flattening and a change of the polarity of the T wave. Autopsy and histological examination of the heart of the infected calves performed 111 days and 250 days after the infection revealed an attacking of the cardiac muscle by cysticerci and dispersed chronic myocarditis. This finding and the investigated dynamics of pathological changes in the course of cysticercosis in other experimental animals indicate that at the time of the electrocardiographic examination cysticercoid myocarditis at a stage of rest was recorded.  相似文献   

12.
A two-year-old Large White boar from a pig breeding stock in an indoor farm in Switzerland presented anorexia, reduced general condition and fever. Despite antibiotic and anti-inflammatory treatment, the boar developed severe dyspnoea and cyanosis, and died after 4 days. At necropsy, no gross lesions were observed. Histopathologically, multifocal degeneration and necrosis of myocardial fibers with interstitial edema, severe multifocal non-suppurative myocarditis and hepatitis, and non-suppurative interstitial nephritis were observed. In heart samples, groups of organisms resembling apicomplexan tachyzoites were seen associated with the lesions. A PCR using the primers COC1-COC2 that target a conserved region of the small-subunit rRNA gene of Apicomplexa was performed with DNA from paraffin-embedded tissues. An amplification product of about 350 bp was obtained from heart samples. A sequence analysis showed 100% identities with GenBank sequences reported for Sarcocystis miescheriana. The histopathological observations and molecular findings in combination with the clinical signs, and absence of other pathologic agents highly suggested that an acute infection with S. miescheriana was the cause of death in this boar. To our knowledge, this the first report of fatal acute sarcocystosis after natural infection in a pig breeding herd.  相似文献   

13.
OBJECTIVE: To describe cardiac lesions and identify risk factors associated with myocarditis and dilated cardiomyopathy (DCM) in beach-cast southern sea otters. ANIMALS: Free-ranging southern sea otters. PROCEDURE: Sea otters were necropsied at the Marine Wildlife Veterinary Care and Research Center from 1998 through 2001. Microscopic and gross necropsy findings were used to classify sea otters as myocarditis or DCM case otters or control otters. Univariate, multivariate, and spatial analytical techniques were used to evaluate associations among myocarditis; DCM; common sea otter pathogens; and potential infectious, toxic, and nutritional causes. RESULTS: Clusters of sea otters with myocarditis and DCM were identified in the southern aspect of the sea otter range from May to November 2000. Risk factors for myocarditis included age, good body condition, and exposure to domoic acid and Sarcocystis neurona. Myocarditis associated with domoic acid occurred predominantly in the southern part of the range, whereas myocarditis associated with S. neurona occurred in the northern part of the range. Age and suspected previous exposure to domoic acid were identified as major risk factors for DCM. A sample of otters with DCM had significantly lower concentrations of myocardial L-carnitine than control and myocarditis case otters. CONCLUSIONS AND CLINICAL RELEVANCE: Cardiac disease is an important cause of death in southern sea otters. Domoic acid toxicosis and infection with S. neurona are likely to be 2 important causes of myocarditis in sea otters. Domoic acid-induced myocarditis appears to progress to DCM, and depletion of myocardial L-carnitine may play a key role in this pathogenesis.  相似文献   

14.
Inflammatory processes induced by viral or bacterial infections are believed to be one of the major pathogenetic mechanisms in myocardial diseases. Although the reason for progression to myocardial failure is not fully understood, postulated mechanisms include persistent viral infection alone or in combination with autoimmune processes. A variety of cardiotropic viruses have been identified to elicit myocarditis, with enteroviruses and adenoviruses as the most frequent causative agents in children and adolescents. However, parvovirus B19 (PVB19) has recently emerged as another potential pathogen in adult patients associated with inflammatory heart disease. Many dimensions of inflammatory heart disease coexist while different phases of the disease progress simultaneously: phase 1 is dominated by viral infection, phase 2 by the onset of (probably) multiple autoimmune reactions, and phase 3 by the progression to cardiac dilatation without the role of an infectious agent and cardiac inflammation. Taking these mechanisms into account, screening for viral and bacterial genome by polymerase chain reaction (PCR) and detection of inflammatory infiltrates by immunohistochemistry are considered crucial for establishing an aetiological diagnosis, thereby allowing initiation of specific therapeutic strategies. In a large cohort of 3345 consecutive patients with left ventricular dysfunction evaluated over a period of 10 years, prevalence of PVB19, coxsackievirus (CVB), human cytomegalovirus (HCMV), influenza A virus and adenovirus (ADV) genome was assessed by PCR. Inflammatory infiltrates within the myocardium were detected by immunohistochemistry according to the WHF criteria and by histopathology according to the Dallas criteria of myocarditis. For control, endomyocardial samples of patients with arterial hypertension were studied. Parvovirus B19 was the most often detected virus in all patient subgroups, with positivity ranging from 17% to 33%. Except for PVB19, CVB RNA (3%), ADV (2%) and CMV (3.9%) were the most frequently detected viral genomes. Interestingly, detection of PVB19 genome was significantly correlated with inflammatory heart disease and reduced ejection fraction. Importantly, an aetiological diagnosis requires the immunohistochemical and molecular biological investigation of endomyocardial biopsies. Such an approach may change the management of these diseases in the future. One of the aims of the study was to reveal the underlying dominant pathophysiological mechanisms in a for deciding on the most approriate therapy.  相似文献   

15.
Sarcocystosis was diagnosed in 41 eighteen-month-old heifers and steers. Clinical signs included anorexia, severe weight loss, nervousness, hypersalivation, lameness, and hair loss on the extremities. Hair loss was noticed especially at the end of the tail, where there was complete loss of the switch, giving the animals a "rat-tail" appearance. Consistent gross changes observed at necropsy of four affected animals included generalized lymphadenopathy, erosions and ulcerations in the oral cavity and esophagus, and severe laminitis. Microscopically, young cysts of Sarcocystis sp were disseminated in the heart, skeletal muscle, and brain. Ultrastructural examination indicated that the cysts were young because they contained metrocytes. Affected animals had moderate to severe nonsuppurative myocarditis and myositis, with focal degeneration of myofibers and infiltration by macrophages, lymphocytes, and plasma cells. Indirect hemagglutination of sera from 19 animals revealed a mean antibody titer of 1:24,000 against Sarcocystis bovicanis antigen. Epidemiologic investigation incriminated resident farm dogs that had been housed in a farm hayloft as the source of infection. Hay contaminated with sporocysts in dog feces was thought to have been fed to the heifers and steers.  相似文献   

16.
Porcine circovirus type 2 was detected in several stillborn and nonviable neonatal piglets presenting with chronic passive congestion, cardiac hypertrophy, and severe diffuse myocarditis. The presence of the virus in the heart and other tissues of affected piglets was confirmed by polymerase chain reaction, immunohistochemistry, and virus isolation techniques. Other reproductive losses and associated infectious agents in the herd are discussed.  相似文献   

17.
Anaplasma marginale infections were induced in 3 calves previously affected with neonatal immunohemolytic anemia (NIA). Similar infections were induced in 6 splenectomized and 7 intact calves. The response to infection by 3 calves (NIA recovered) closely resembled infections seen in splenectomized calves, being markedly more severe than similar infections in intact calves. Spleens from 3 (NIA recovered) calves after splenectomy were about one-tenth normal size. Marked recrudescing anaplasmal infections were not detected after splenectomy of the calves (NIA recovered), whereas marked recrudescing infections were observed after splenectomy of 2 intact calves having recovered from the primary infections.  相似文献   

18.
Encephlitozoonosis was induced in 35 of 38 vervet monkeys (Cercopithecus pygerythrus). They were either directly (orally) inoculated with Encephlitozoon cuniculi or indirectly exposed to this protozoan parasite. Cell-culture-grown spores of E. cuniculi, isolated from the kidneys of dogs with natural, fatal disease, were administered orally to 29 of these monkeys. Another 5 were exposed in utero by orally infecting pregnant females, and 3 were exposed to horizontal infection by nursing infected infants. Only one was given an intravenous inoculation of spores. The disease was induced in non-gravid and late-pregnant adults, immunocompetent infants, and in infants that were immunologically compromised by parenteral steroid administration, as well as in one infant that was immunologically immature because of its premature birth. The effects of age, dosage, post-inoculation (PI) interval, passage level of the parasite in cell culture and immunological status of the host were correlated with macroscopical and microscopical lesions. The experimentally induced infection was confirmed either by reisolation of the parasite in cell culture or by observation of spores in tissue sections. Both confirmatory methods were supported by serological examination. Reisolation of the organism in primary cell culture prepared from kidneys usually resulted in more frequent isolates and larger yields of spores from infants than from adult vervets. Infection with E. cuniculi invariably induced subclinical disease. Based on histology, lesions were minimal to moderately severe, depending on age, PI interval, and immunological status of the host. Alimentary tract infections were seen histologically as early as three days PI. Subsequently, infections resulted in detectable lesions most consistently in the liver, kidneys and brain. Lesions in these organs were generally granulomatous and were similar to those found in canine encephalitozoonosis. In addition, multifocal interstitial pneumonitis and myocarditis as well as vasculitis and perivasculitis were seen in other tissues and organs. Infants had more severe and more widespread lesions than adults. Although lesions and spores were still present in the brain of one immunocompetent infant 36 weeks after initial infection, the disease in immunocompetent infants and adults is thought to be self-limiting. However, infection may persist. Immunological depression favoured increased growth and multiplication of the organism, and resulted in detection of more spores within inflammatory lesions as well as more intracellular colonies of the organism that were free of inflammatory reaction.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

19.
A severe outbreak of erysipelas causing high mortality was observed in Coturnix breeder quails. Possible source(s) of erysipelothrix infection in the flock and subsequent infections due to Pasteurella multocida, Salmonella typhimurium, and Staphylococcus aureus are discussed.  相似文献   

20.
Pigs selected for high (H) or low (L) combined antibody and cell-mediated immune response were infected with Mycoplasma hyorhinis. Following the infection, arthritis was more severe in the H pigs, while pleuritis and peritonitis were more severe in the L pigs. Since Mycoplasma infections in pigs often cause just mild signs, indicators of the inflammatory response may aid diagnosis of such infections. In addition, data about the genetic influence on inflammatory response indicators are scanty in the pig. The objectives of the study were therefore: firstly, to determine interferon-alpha (IFNalpha) and haptoglobin in M. hyorhinis infected pigs and, secondly, to investigate if the inflammatory response as determined by these indicators was influenced by genetic selection. There was no consistent increase of IFN-alpha in serum following infection. The serum haptoglobin concentration started to increase 3 days post-infection and there was no difference between the two breeding lines. Hence, M. hyorhinis infection in pigs is reflected in increased serum haptoglobin concentration, but no effect of the magnitude of the inflammatory response on this indicator by selection for high or low immune response was observed.  相似文献   

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