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991.
A bacterin containing serotypes 1 and 5 of Haemophilus pleuropneumoniae was developed for the prevention and the control of porcine pleuropneumonia. It was injected intramuscularly into three groups of ten piglets, the first group with one dose, the second one with two doses and the third one with three doses at two-week intervals. Another group of ten piglets did not receive the vaccine. All the piglets were then challenged by an aerosol of mixed suspensions of H. pleuropneumoniae serotypes 1 and 5. Two and three injections of vaccine completely prevented mortality, whereas half of the control piglets and of those receiving only one dose of vaccine died. All surviving piglets, both control and vaccinated, had severe signs of respiratory disease for at least 36 hours after exposure to challenge. Moreover, vaccination did not induce the production of antibodies at high titers. Local reactions were not noted after vaccination and at postmortem; ten weeks after the challenge, there were no signs of abscess formation or induration.  相似文献   
992.
The serological responses of calves at two different ages to a commercial hardjo/pomona vaccine were examined. Microscopic agglutination test (MAT) titres of a group of ten three-month-old calves and three groups of 11,12 and 12 six-month-old calves were monitored over a period of 28 weeks. The calves vaccinated at three months of age had a poorer serological response rate to vaccination (30% responded to pomona and 40% responded to hardjo) compared with those vaccinated at six months of age (91-100% responded to pomona and 83-91% responded to hardjo). Those three-month-old calves which did respond also produced a lower level of-antibody than six-month-old calves. It was concluded that in order to achieve adequate protection using commercially available leptospiral bacterins at the recommended dose, vaccination should not be undertaken routinely with animals less than six months of age. Where circumstances arise in which earlier vaccination is necessary, repeat vaccination for continued protection at six months or older is suggested.  相似文献   
993.
Lytic lesions occurring in conjunction with plasma cell sarcoma (multiple myeloma) have rarely been reported in cats.

A plasma cell sarcoma was diagnosed in a 13 year old castrated male Siamese cat with hind limb paresis resulting from osteolysis of the second lumbar vertebra. Serum electrophoresis showed a monoclonal gammopathy. A uniform population of plasma cells was found in and around the second lumbar vertebra and in the bone marrow of the femora, humeri, pelvis and the fifth lumbar vertebra. The neoplastic cells were identified as IgA and kappa chain specific by direct immunofluorescence.

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Two cases of noninfectious, nonerosive arthritis are presented. The diagnostic features, clinical course and treatment are reviewed. Potential etiologies are discussed in the light of relatively little current material on this subject in the veterinary literature.  相似文献   
997.
Pemphigus and pemphigoid are uncommon dermatological entities in domestic animals and of a presumed autoimmune nature. In one form or another, they have been reported in the dog, cat, horse and goat. Although these diseases are considered to be bullous dermatoses, the clinical presentation may vary from ulcerative to exfoliative to proliferative depending on the individual condition. Currently, four variants of pemphigus are recognized (vulgaris, vegetans, foliaceus, erythematosus) and two of pemphigoid (bullous, cicatricial) although cicatricial pemphigoid has not yet been conclusively demonstrated in animals. Diagnosis is based on history, clinical signs, histopathology and immunopathology. Therapy must be immunosuppressive to be effective and is palliative rather than curative.  相似文献   
998.
Reference ranges for five parameters of blood coagulation were established in clinically normal farmed fallow deer (Dama dama) and red deer (Cervus elaphus). Storage of plasma at -15 degrees C resulted in small increases in activated partial thromboplastin time (APTT) for both species, and in the one stage prothrombin time (OSPT) of fallow deer, between days 1 and 30. These times were then stable between days 30 and 60. The fibrinogen levels of fallow deer plasma showed a small apparent increase over 60 days. These storage artefacts were not of sufficient magnitude to preclude the use of such plasma for diagnostic purposes although they could limit its use in research. Levels of fibrin/fibrinogen degradation products (FDP) were not affected by storage at -15 degrees C. Rabbit brain thromboplastin appeared adequate for OSPT determination in both species. The activated clotting time (ACT) is recommended as a field test for screening the intrinsic and common pathways of blood coagulation in deer.  相似文献   
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