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891.
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A four day old Holstein calf was presented with a history of recurrent free gas bloat. An exploratory laparotomy was performed and no abnormalities were discovered in the gastrointestinal tract. An esophagotracheal fistula was suspected and confirmed by endoscopy. Surgical correction was performed by ligating the tubular connection between the trachea and esophagus and suturing closed the defects in these structures.  相似文献   
895.
A one month old Quarterhorse colt was presented after a week history of bilateral nasal discharge and respiratory difficulty. The cervical esophagus was greatly dilated, tortuous and filled with diluted milk. A nasogastric tube could not be passed beyond the base of the heart. An aspiration pneumonia was found at postmortem examination and the esophageal segment from the pharynx to the base of the heart was dilated, thin-walled, had degenerative muscular changes, and a reduction in size and number of ganglion cells of the myenteric plexus. Muscular hypertrophy of the terminal esophagus had reduced its lumen size. Some similarities and disparities of this condition to achalasia of man and megaesophagus of dogs are discussed.  相似文献   
896.
Cervical intervertebral disc protrusion in two horses   总被引:2,自引:1,他引:1  
Two horses with ataxia of all four limbs were found to have cervical intervertebral disc protrusion. Severe pelvic limb ataxia, proprioceptive deficits and spasticity were present in both horses with similar but less severe signs in the thoracic limbs. Cerebrospinal fluid analysis was within normal limits. Metrizamide myelography allowed definitive diagnosis in one case when a compression of the spinal cord was demonstrated at the level of the second intervertebral space. In the second case, an intervertebral disc protrusion between cervical vertebrae 6 and 7 was found at necropsy. Fiber degeneration with poor myelin staining characterized the spinal cords histologically.  相似文献   
897.
898.
A herd of 180 beef cows was synchronized with prostaglandin and bred by artifical insemination for five successive years. Factors influencing the success or failure of estrus synchronizing programs were identified, including the management of nutrition, postpartum interval, cow age and artificial insemination technology. Specific recommendations on the management of prostaglandin-controlled breeding programs resulted in improving the pregnancy rates from 33% in year 1 to 67% in year 5. Improved management and close veterinary supervision were shown to improve the success of an estrus synchronization program.  相似文献   
899.
Year end tax planning   总被引:1,自引:1,他引:0       下载免费PDF全文
  相似文献   
900.
This paper concerns the taxonomic status of the F38-like group (MacOwan), a prime determinant of contagious caprine pleuropneumonia (CCPP). Extensive biochemical and serological investigations on strain F38 are reported. Some complex serological relationships with other mycoplasma species are revealed. The results, taken in conjunction with earlier published work on geno-typic characters, lead to the conclusion that final classification of these organisms should await further comparative studies of a number of field strains with a related group of strains classified as M. capri-colum.The characterization of F38 confirms its partial relationship to the “M. mycoides group” of ovine/caprine/bovine mycoplasmas, and has also revealed a very close phenotypic relationship to the bovine mycoplasma serogroup 7, a finding of potential diagnostic and epidemiological importance.Key words: mycoplasmas, classification, F38-like group  相似文献   
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