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981.
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984.
Type C botulism in intensively farmed turkeys   总被引:1,自引:0,他引:1  
Type C botulism in turkeys has been confirmed on several production sites by demonstrating the presence of toxin in sera from affected birds. Only male turkeys were affected, mortalities being up to 30 per cent. No source of toxin was found. Possible modes of intoxication are discussed.  相似文献   
985.
Bile duct obstruction was induced in 6 cats by surgical ligation and transection of the common bile duct. Clinical and laboratory changes were monitored weekly for 25 to 54 days. Clinical signs of obstruction were similar in all cats and included anorexia, pyrexia, lethargy, intermittent vomiting, weight loss, palpable gallbladder, hepatomegaly, and bleeding tendencies. Tissue jaundice and acholic feces were evident grossly as early as postsurgical day (PSD) 4 with a mean onset of jaundice at PSD 5.3 +/- 0.4. Hematologic changes were initially characterized by a mild neutrophilic leukocytosis that increased with the chronicity of bile duct obstruction. Regenerative anemia developed in 4 cats associated with gastrointestinal blood loss. Acute serum biochemical changes were characterized by a marked increase in the mean values of aspartate aminotransferase, alanine aminotransferase, total cholesterol, and copper. Comparatively, only moderate increases in mean serum alkaline phosphatase activity were observed. Mean total bilirubin values increased remarkably at postsurgical week (PSW) 1, reaching a maximal value of 23.1 +/- 4.4 mg/dl at PSW 3 with 71.6 +/- 2.7% direct bilirubin. With chronicity of bile duct obstruction ranging from PSW 3 to PSW 7, the mean serum values of aspartate aminotransferase, alanine aminotransferase, total cholesterol, serum alkaline phosphatase, and total and direct bilirubin stabilized and then declined, whereas the increased mean serum copper values persisted. At PSD 25 to 54, hepatic copper values and serum bile acids were markedly increased. Seemingly, clinicopathologic changes of induced cholestatic hepatic injury depended largely on the duration of biliary obstruction.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
986.
Twenty-one experimental oil-emulsion vaccines with different emulsifier contents, aqueous-to-oil ratios, and antigen concentrations were compared by immunization of 4-week-old chickens. Vaccines that contained oil-phase (Arlacel 80) and aqueous-phase (Tween 80) emulsifiers induced 2-to-4-fold higher hemagglutination-inhibition titers than vaccines with only the oil-phase emulsifier. The emulsion vaccines containing both emulsifiers were also more stable at 37 C and less viscous than those containing only the oil-phase emulsifier. Vaccines that had different aqueous-to-oil ratios and contained different quantities of allantoic-fluid antigen (1.2% to 50% of the vaccine volume) induced similar protection against challenge, but hemagglutination-inhibition titers were proportional to the amount of antigen added. Vaccines that had different aqueous-to-oil ratios but contained equal amounts of antigen induced similar hemagglutination-inhibition titers and similar protection against challenge.  相似文献   
987.
A 31-year-old captive male African elephant (Loxodonta africana) of 5,000-kg body weight died suddenly in ventral recumbency. Lesions seen at necropsy were bilateral purulent pulpitis and periodontitis of both tusks, serous atrophy of coronary groove fat, Grammocephalus cholangitis, myocardial and skeletal lipofuscinosis, and scattered segmental necrosis in the pectoral muscles. Nonhemolytic streptococci, Corynebacterium sp, Peptostreptococcus anaerobius, Fusobacterium nucleatum, and Bacteroides sp, were recovered from the exudate around one or both tusks. We postulated that the elephant died of hypoxia from prolonged ventral recumbency because of weakness and inability to rise secondary to toxemia from bilateral pulpitis and periodontitis.  相似文献   
988.
Immunization of ewes with oil emulsion toxoid followed by an aluminium phosphate-adsorbed toxoid both containing 10 Lf per dose, resulted in a very high antitoxin level in their lambs. Two injections of aluminium phosphate-adsorbed toxoid also imparted a passive immunity to lambs which is considered to be adequate to protect them against tetanus for 4 weeks after birth.  相似文献   
989.
Primary Pseudomonas aeruginosa ulcerative keratitis and accompanying secondary ocular disease were induced bilaterally in 12 of 12 dogs subjected to corneal trephination and intrastromal inoculation. Successful experimental infection was based on recovery of viable Pseudomonas organisms from the lesions, as well as gross and biomicroscopic appearance of the corneas.  相似文献   
990.
Three conditions of the cornea in the dog are described; a form of corneal dystrophy (central/paracentral lipid dystrophy, lipidosis, lipoidosis, cholesterolosis), degeneration (fatty and calcareous degeneration) and infiltration (arcus lipoides corneae, anterior embryotoxon, pre-senile arcus). The clinical appearance, together with histopathological and ultrastructural details, are recorded. The age, sex, breed incidence and possible hereditary factors are also included. Reference is made to previous reports in the veterinary literature and the three conditions are compared with similar conditions in man.  相似文献   
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