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Glasser's disease and prevalence of subclinical infection with Haemophilus parasuis in swine in southern Ontario 
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下载免费PDF全文 Smart NL Miniats OP Rosendal S Friendship RM 《The Canadian veterinary journal. La revue veterinaire canadienne》1989,30(4):339-343
Glasser's disease accounted for less than 1% of total swine mortalities in an 11 year retrospective postmortem survey of swine submissions at three provincial government diagnostic laboratories in southern Ontario. However, Glasser's disease was suspected in 17 of 83 boar mortalities at the Record of Production Boar Test Station between 1983 and 1985 and was much more common in specific-pathogen-free (SPF) boars than in conventional boars. The prevalence of the causative organism, Haemophilus parasuis, was determined for 19 SPF herds in Ontario classified as "Excellent" under the Ontario Swine Herd Health Policy. Nasal swabs from two-month-old pigs were cultured on chocolate agar containing 1.5 mug/mL lincomycin, 5 mug/mL bacitracin, and 0.1 mug/mL crystal violet. Three herds were negative for H. parasuis infection; 16 herds contained clinically healthy carrier pigs. 相似文献
994.
M R Baxter 《Journal of animal science》1989,67(9):2433-2440
The concept of coping can be used to relate the environmental conditions provided for livestock to their responses--their productivity and their welfare. Pigs are "ecological generalists" and hence are "designed" to cope with a wide variety of environmental conditions. They, however, show clear limits to their adaptability both in terms of the space they require and the pen materials they can endure without injury. Even where they adapt to a wide range of conditions, there often is a particular environment that gives optimum performance. Examples of temperature requirements and feeding facilities are discussed. The process of coping is shown to impose a biological "cost" in some instances and, although a pig has adapted to a specific environment, questions still remain concerning whether keeping a pig in that environment is justifiable. 相似文献
995.
Canine congenital aortic stenosis: A review of the literature and commentary 总被引：2，自引：0，他引：2 下载免费PDF全文
下载免费PDF全文 O'grady MR Holmberg DL Miller CW Cockshutt JR 《The Canadian veterinary journal. La revue veterinaire canadienne》1989,30(10):811-815
Congenital aortic stenosis usually affects the subvalvular region, and occurs mainly in Newfoundland, Golden Retriever, German Shepherd, and Boxer dogs. The disorder is inherited as a dominant trait with variable penetrance in Newfoundland dogs.
The prevalence of subaortic stenosis-like heart murmurs in Golden Retriever dogs appears to be very much greater than previously suspected.
Most cases of aortic stenosis represent mild lesions, are detected as incidental findings, and result in no loss of longevity or quality of life. Moderate or severe stenosis may result in exertional weakness, syncope, or sudden death. Signs of congestive heart failure are rare unless mitral valve insufficiency is present.
Generally, electrocardiography and radiography are unrevealing in this disorder. Doppler echocardiography may be the best diagnostic tool to detect even mild cases of aortic stenosis.
At present, therapy is limited due to the technical expertise and expense required. The prognosis depends on the severity of the lesion.
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