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Porcine respiratory coronavirus (PRCV) is present in many countries, including Canada, but controversy still exists concerning its pathogenicity. Eight-week-old piglets were inoculated intratracheally with a Quebec PRCV isolate (1Q90). Two contact piglets were kept with the inoculated animals. Three animals served as control. Polypnea and dyspnea were the main clinical signs observed. Diffuse bronchioloalveolar damage occurred 24 hours postinoculation. Changes compatible with bronchointerstitial pneumonia were present six days postinoculation. The inoculated virus was recovered from the respiratory tract and mesenteric lymph nodes, but not from the digestive tract, of the inoculated as well as the contact piglets. No virus was isolated from the control piglets. The development of clinical signs and histopathological changes in inoculated as well as in contact piglets and the reisolation of the inoculated virus demonstrated that PRCV can be an important respiratory pathogen.  相似文献   

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An outbreak of infectious rhinotracheitis affecting four herds of dairy cattle was observed in the Province of Quebec, the general characteristics of which are the same as those reported in the infection of feedlot cattle.

However, a 25% average decrease in the milk production of affected herds was noticed during the present infection, thus stressing a particular economic aspect. The nature of the viruses isolated during this outbreak and those described previously in North America is identical.

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Presence of the bacterial kidney disease in salmonid fish in Quebec During the summers of 1979 and 1980, wild and hatchery fish were analysed for the presence of the bacterial kidney disease (BKD) agent in salmonid fish in Quebec by the indirect immunofluorescence technique. The causative agent of BKD was detected in all hatcheries tested. Ten to 25% of the fish were positive. The presence of this agent was independent of age and species. We were unable to detect the BKD in fish from the rivers in the northern part of Quebec (over the 50th parallel).  相似文献   


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