101
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Artsob H, Spence L, Surgeoner G, McCreadie J, Thorsen J, Th'ng C, Lampotang V. Isolation of Francisella tularensis and Powassan virus from ticks (Acari: Ixodidae) in Ontario, Canada. JOURNAL OF MEDICAL ENTOMOLOGY 1984; 21:165-168. [PMID: 6327984 DOI: 10.1093/jmedent/21.2.165] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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102
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Chui CH, Thorsen J. Experimental Infection of Turkeys with Infectious Bursal Disease Virus and the Effect on the Immunocompetence of Infected Turkeys. Avian Dis 1984. [DOI: 10.2307/1590142] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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103
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Brookman DH, Chopra C, Ecobichon DJ, Kang CY, Ritter L, Thorsen J. Assessment of the potential of insecticides, emulsifiers, and solvent mixtures to enhance viral infection in cultured mammalian cells. Appl Environ Microbiol 1984; 47:80-3. [PMID: 6320724 PMCID: PMC239615 DOI: 10.1128/aem.47.1.80-83.1984] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Various insecticides, solvents, emulsifiers, and mixtures thereof were tested to determine whether these compounds are capable of enhancing the sensitivity of cultured mammalian cells to infection with vesicular stomatitis virus. None of 42 compounds tested significantly enhanced the viral infection.
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104
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Chui CH, Thorsen J. Experimental infection of turkeys with infectious bursal disease virus and the effect on the immunocompetence of infected turkeys. Avian Dis 1984; 28:197-207. [PMID: 6326741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Turkeys of various ages were infected with strains of infectious bursal disease virus (IBDV). Pathological signs of infection were detected only in turkeys 1 day old when infected. No differences in antibody responses to IBDV or virus recovery were observed between turkeys of various ages at the time of infection. Cellular and humoral immune responses were suppressed following infection of day-old turkeys. The effects varied with virus strain.
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105
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Thorsen J, Willoughby RA, McDonell W, Valli VE, Viel L, Bignell W. Influenza hemagglutination inhibiting activity in respiratory mucus from horses with chronic obstructive pulmonary disorders (heaves syndrome). CANADIAN JOURNAL OF COMPARATIVE MEDICINE : REVUE CANADIENNE DE MEDECINE COMPAREE 1983; 47:332-5. [PMID: 6640415 PMCID: PMC1235948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Samples of mucus from the lower trachea were collected from 53 horses with chronic obstructive pulmonary disease and from 24 clinically normal horses. Serum samples were collected from 35 of the horses with chronic obstructive pulmonary disease and from the 24 normal horses. Samples were tested for inhibition of hemagglutination by influenza A equine 1 and 2 viruses. There were high levels of hemagglutination inhibiting activity against influenza A equine 1 in mucus samples from horses with chronic obstructive pulmonary disease.
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106
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Artsob H, Spence L, Surgeoner G, Helson B, Thorsen J, Grant L, Th'ng C. Snowshoe hare virus activity in Southern Ontario. CANADIAN JOURNAL OF PUBLIC HEALTH = REVUE CANADIENNE DE SANTE PUBLIQUE 1982; 73:345-9. [PMID: 6129057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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107
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Thorsen J, Weninger N, Weber L, Dijk CV. Field Trials of an Immunization Procedure against Hemorrhagic Enteritis of Turkeys. Avian Dis 1982. [DOI: 10.2307/1589892] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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108
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Eyre P, Gaviller P, Thorsen J. Equine influenza virus enhances responsiveness of guinea-pig tracheal muscle to isoprenaline. RESEARCH COMMUNICATIONS IN CHEMICAL PATHOLOGY AND PHARMACOLOGY 1982; 37:3-10. [PMID: 7123002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Groups of guinea-pigs were vaccinated with equine influenza A-1 virus and helically-cut tracheal strips were subsequently contracted to carbachol (EC50) and relaxed to isoprenaline at 3, 5 and 10 days post-vaccination. Tracheas from another group were contracted to phenylephrine in the presence of propranolol. Compared to controls, responses to isoprenaline in virus-infected tracheas were significantly potentiated at days 3 and 10. Virus infection significantly inhibited tracheal responsiveness to phenylephrine. It appears that enhancement of isoprenaline may be caused by diminished reactivity of the alpha-adrenoceptor system, thus promoting airway dilatation caused by the beta-adrenoceptor agonist.
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109
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Thorsen J, Weninger N, Weber L, Van Dijk C. Field trials of an immunization procedure against hemorrhagic enteritis of turkeys. Avian Dis 1982; 26:473-7. [PMID: 6293440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The efficacy of oral vaccination for hemorrhagic enteritis of turkeys was assessed by comparing flocks raised on the same premises, under the same management, with and without vaccination. The immunizing virus, a strain of marble spleen disease virus of pheasants, was administered via the drinking water. Vaccinated and unvaccinated turkeys differed significantly in feed conversion rates and spleen weights after challenge.
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110
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Humphrey JD, Little PB, Stephens LR, Barnum DA, Doig PA, Thorsen J. Prevalence and distribution of Haemophilus somnus in the male bovine reproductive tract. Am J Vet Res 1982; 43:791-5. [PMID: 7091841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
"Haemophilus somnus' was isolated from 77% of 31 reproductive tracts of bulls from an Ontario slaughterhouse. Identification of H somnus was based on morphologic and cultural characteristics and on fluorescent antibody and immunodiffusion tests, using antisera prepared against a known pathogenic encephalitic isolate of H somnus. The infection rate and distribution of H somnus within the tract were as follows: preputial orifice--71% preputial cavity--71%; urinary bladder--26%; accessory sex glands--19% and ampulla of ductus deferens--10%. Isolates were not obtained from the testes or epididymides. On 2 occasions, H somnus was isolated in pure culture from the preputial cavity. A higher prevalence of infection was found in young bulls. There were no differences found in infection rates between breeds. Differences in hemolytic activity and minor antigenic variation between isolates indicated that a series of biotypes within the species H somnus may exist. The study indicates that organisms presently identified as H somnus may normally form part of the flora of the bovine prepuce and that dissemination from the male bovine reproductive tract is one possible means of infection in H somnus-associated diseases. The pathogenic significance of genital isolates of H somnus awaits further study.
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111
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Humphrey JD, Little PB, Barnum DA, Doig PA, Stephens LR, Thorsen J. Occurrence of "Haemophilus somnus" in bovine semen and in the prepuce of bulls and steers. CANADIAN JOURNAL OF COMPARATIVE MEDICINE : REVUE CANADIENNE DE MEDECINE COMPAREE 1982; 46:215-7. [PMID: 7093816 PMCID: PMC1320285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Haemophilus somnus was isolated from 40 of 79 unprocessed bovine semen samples, 14 of 23 preputial washings of bulls and three of eight preputial washings of steers. The results indicate nonvenereal colonization of the male urogenital tract. It is suggested that dissemination of H. somnus from the urogenital tract may be of significance in the epizootiology of H. somnus associated diseases.
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112
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McKinnon AO, Thorsen J, Hayes MA, Misener CR. Enzootic nasal adenocarcinoma of sheep in Canada. THE CANADIAN VETERINARY JOURNAL = LA REVUE VETERINAIRE CANADIENNE 1982; 23:88-94. [PMID: 17422121 PMCID: PMC1790125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
A survey of veterinary diagnostic laboratories revealed that intranasal tumors occur in sheep in most provinces of Canada. Tumors were diagnosed in 44 sheep of several breeds including Polled Dorset, Suffolk, Cheviot, Rambouillet and various crossbreeds. Twenty-seven percent of tumors occurred in sheep that were less than two years old. Most tumors were sporadic but 33% of cases occurred in six related flocks, indicating that this disease can be an enzootic problem. The clinical signs were persistent serous, mucous or mucopurulent nasal discharge and stridor. Affected sheep progressively developed anorexia, dyspnea and mouth breathing and most died from effects of asphyxia and inanition within 90 days of the onset of clinical signs. Tumors originated unilaterally or occasionally bilaterally in the olfactory mucosa of the ethmoid turbinates. They were expansive and sometimes locally invasive but metastases were not found. Histologically, the tumors were classified as adenomas or, more frequently, adenocarcinomas. The etiology was not established but retrovirus like particles were observed in tumor tissue from one affected sheep.
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113
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Howie RI, Thorsen J. Identification of a strain of infectious bursal disease virus isolated from mosquitoes. CANADIAN JOURNAL OF COMPARATIVE MEDICINE : REVUE CANADIENNE DE MEDECINE COMPAREE 1981; 45:315-20. [PMID: 6280817 PMCID: PMC1320226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The Becht strain of infectious bursal disease virus was compared with a virus isolated from Aedes vexans mosquitoes and designed 743 virus. The viruses were compared with respect to cell culture host range, cellular changes resulting from viral infections, growth curves, antigenic relationship, and physicochemical characteristics. The viruses are closely comparable in all these properties, and they are considered to be strains of the same virus. In cross comparisons by the enzyme-linked immunosorbent assay, 743 virus and infectious bursal disease virus were found to be antigenically identical, confirming the results of the neutralization test. The 743 virus differs from most strains of infectious bursal disease virus in that it is nonpathogenic for chickens.
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114
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Silim A, Thorsen J. Hemorrhagic enteritis: virus distribution and sequential development of antibody in turkeys. Avian Dis 1981; 25:444-53. [PMID: 6266390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Turkeys poults were inoculated intraperitoneally with hemorrhagic enteritis virus (HEV) at 4-1/2 weeks of age. Antibody response and sequential development of viral antigen in various tissues were monitored. An enzyme-linked immunosorbent assay (ELISA) was developed to study antibody production, and immunoperoxidase staining was used to determined sites of localization of the viral antigens in tissues. Results of ELISA and immunodiffusion tests were compared. ELISA detected antibody from day 3 post-infection (p.i.), and gel diffusion detected antibody from day 5 p.i. Peak ELISA antibody titer appeared from day 14 p.i. HEV antigen was detected from 2-6 days p.i. in the spleen, liver, intestine, kidney, and bone marrow; peak titers in the spleen were on day 3 p.i. Virus was not detected after day 6 p.i.
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115
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Silim A, Thorsen J. Hemorrhagic Enteritis: Virus Distribution and Sequential Development of Antibody in Turkeys. Avian Dis 1981. [DOI: 10.2307/1589936] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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116
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Howie R, Thorsen J. An enzyme-linked immunosorbent assay (ELISA) for infectious bursal disease virus. CANADIAN JOURNAL OF COMPARATIVE MEDICINE : REVUE CANADIENNE DE MEDECINE COMPAREE 1981; 45:51-5. [PMID: 6268265 PMCID: PMC1320120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The application of the indirect enzyme-linked immunosorbent assay (ELISA) for detection of infectious bursal disease virus antibodies in chicken serum was investigated. The test procedure involved the coating of concentrated infectious bursal disease virus antigen onto polystyrene tubes, followed by the addition of chicken anti-infectious bursal disease virus serum and horseradish peroxidase labeled rabbit anti-chicken globulin. As an indicator substrate, 5-aminosalicylic acid, with the oxidant H2O2 was added. The reaction was stopped by 3M NaOH and the colour intensity of the reaction mixtures read in a spectrophotometer at 449 nm. The ELISA test was found to be a precise, sensitive and reproducible means of measuring infectious bursal disease virus antibodies in chicken and turkey sera.
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117
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Thorsen J, Barker IK, Hinshaw VS. Influenza viruses isolated from waterfowl in southern Ontario, 1976-1978. Can J Microbiol 1980; 26:1511-4. [PMID: 7237275 DOI: 10.1139/m80-252] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
From 1976 to 1978, samples were collected from 720 ducks, 100 terns, and 50 gulls for attempted isolation of influenza viruses. Influenza viruses were isolated from 32 of the ducks samples: 10.2% of those sampled in 1976, 4.8% in 1977, and 2.4% in 1978. At least six different hemagglutination and seven neuraminidases were identified in the viruses isolated, in 14 different combinations.
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118
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Thorsen J, Artsob H, Spence L, Surgeoner G, Helson B, Wright R. Virus isolations from mosquitoes in southern Ontario, 1976 and 1977. Can J Microbiol 1980; 26:436-40. [PMID: 6103747 DOI: 10.1139/m80-072] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Following the 1975 epidemic of St. Louis encephalitis (SLE) in Ontario, programs were instituted to monitor virus activity in mosquito populations during 1976 and 1977. Mosquitoes were trapped with CDC light traps and CO2 cone traps, pooled by species, and tested for virus by intracerebral inoculation of suckling mice. In 1976, 51 175 mosquitoes were tested. SLE virus was isolated from two mixed pools of Culex pipiens--C. restuans mosquitoes. Five isolations of California serogroup viruses were made. Three of these were trivittatus virus, which has not been demonstrated previously in Canada, and the other two were snowshoe have virus. Other viruses isolated in 1976 were a virus antigenically identical to the virus of infectious bursal disease of chickens and 34 Flanders viruses. In 1977, 34 428 mosquitoes were tested. Flanders virus was isolated most frequently, from pools of mixed C. pipiens--C. restuans mosquitoes. The only other isolate was a Bunyamwera group virus, Cache Valley virus. This virus has not been reported previously in Ontario.
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119
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Kinyili JH, Thorsen J. Antigenic comparisons between herpesviruses isolated from fallow deer in Alberta and the viruses of infectious bovine rhinotracheitis, equine rhinopneumonitis and DN-599, a non-IBR bovine herpesvirus. J Wildl Dis 1979; 15:339-41. [PMID: 225575 DOI: 10.7589/0090-3558-15.2.339] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Antigenic comparison studies of three herpesviruses isolated from fallow deer (Dama dama) in Alberta and herpesviruses from some domestic species were carried out by the alpha serum-virus neutralization test. Complete cross neutralization was demonstrated among the deer herpesviruses and equine herpesvirus type 1.
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120
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Sherman J, Mitchell WR, Martin SW, Thorsen J, Ingram DG. Epidemiology of equine upper respiratory tract disease on standardbred racetracks. CANADIAN JOURNAL OF COMPARATIVE MEDICINE : REVUE CANADIENNE DE MEDECINE COMPAREE 1979; 43:1-9. [PMID: 218705 PMCID: PMC1319930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The outbreaks of upper respiratory tract infections in horses at Standardbred racetracks were investigated over a three year period. The most serious epidemics of respiratory disease occurred in the winter and spring seasons. Both influenza viruses and equine herpesvirus 1 were shown to be present in the horse population. The herpesvirus was associated with respiratory disease particularly in the winter but the equine influenza viruses apparently were responsible for the major epidemics of respiratory disease at these tracks. Younger horses, two or three years of age, were particularly susceptible to upper respiratory disease and showed the greatest rate of seroconversion to influenza viruses. Major outbreaks of respiratory disease occurred when the proportion of young horses which had not previously been exposed to epidemics of respiratory disease reached 30 to 40% of the population at the track. Most horses over four years of age appeared to develop resistance to the infections.
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121
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Silim A, Thorsen J, Carlson HC. Experimental Infection of Chickens with Hemorrhagic Enteritis Virus. Avian Dis 1978. [DOI: 10.2307/1589513] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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122
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Silim A, Thorsen J, Carlson HC. Experimental infection of chickens with hemorrhagic enteritis virus. Avian Dis 1978; 22:106-14. [PMID: 206247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Chickens were experimentally infected with hemorrhagic enteritis virus, causing lesions similar to those observed in turkeys. Lesions were induced by intraperitoneal and oral infection. Virus particles with the morphology of adenovirus were demonstrated in the spleens of infected chickens. Splenic extracts from infected chickens caused lesions of hemorrhagic enteritis in turkeys. Recovery from the infection in chickens was followed by the production of antibodies to HEV, demonstrated by agar-gel precipitin test.
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123
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Abstract
Small dermal tumors were found on three African hares (Lepus capensis) in the Laikipia District, Kenya. Gross and histopathologic studies revealed similarities to the Shope's fibroma of wild rabbits in North America and fibromas of European hares. Histological examination of the African hare fibromas revealed intracytoplasmic inclusion bodies characteristic of poxviruses and poxvirus virions were demonstrated by electron microscopy of ultrathin sections. Attempts to propagate the virus in rabbit skin, embryonated chicken eggs and cell cultures were unsuccessful.
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124
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Sherman J, Mitchell WR, Martin SW, Thorsen J, Ingram DG. Control of equine respiratory disease on Ontario Standardbred racetracks. THE CANADIAN VETERINARY JOURNAL = LA REVUE VETERINAIRE CANADIENNE 1977; 18:154-8. [PMID: 880539 PMCID: PMC1697601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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125
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Sherman J, Thorsen J, Barnum DA, Mitchell WR, Ingram DG. Infectious causes of equine respiratory disease on Ontario standardbred racetracks. J Clin Microbiol 1977; 5:285-9. [PMID: 192757 PMCID: PMC274583 DOI: 10.1128/jcm.5.3.285-289.1977] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Upper respiratory disease has been a serious problem in Standardbred horses on racetracks in Ontario, with outbreaks occurring once or twice annually in late winter and early spring seasons. To determine the causes of these epidemics, a 3-year investigation was carried out in which nasal swabs and serum samples were obtained at intervals from apparently healthy horses and from horses suffering from upper respiratory disease. The nasal swabs were used to isolate bacteria and viruses. The serum samples were examined for the presence and level of antibodies to equine influenza viruses and equine herpesvirus 1. None of the bacteria isolated were associated with the outbreaks of disease. Equine herpesvirus 2 was isolated 72 times from both diseased and apparently healthy horses. Equine herpesvirus 1 was isolated 10 times from horses with respiratory disease, both during and between epidemics. Influenza equine/1 virus was isolated seven times and influenza equine/2 was isolated once during severe outbreaks of upper respiratory disease. Serological evidence confirmed that influenza viruses were the causes of the major epidemics, with the equine/1 strain being involved most often.
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