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151.
Clinical hypocalcaemia was associated with single doses of three oi more days; supply of zinc oxide to dairy cows for facial eczema control. Experimental hand dosing of a single dose of zinc oxide (40 and 120 mg Zn/kg b wt) to Jersey cows caused a significant drop in serum calcium concentration at 24 h followed by a rise to concentrations higher than controls at subsequent samplings over four days. At the highest zinc dose rate, 78% of serum calcium values were equal to or lower than the lowest control value at 24 h post dosing. Serum magnesium concentrations had a reciprocal relationship to the calcium levels at all samplings. Serum zinc concentrations were most elevated over the 48 h post dosing, returning to normal levels at the fifth day. Following the highest zinc dose milk yields were reduced by approximately 1.5 kg milk/cow/day for 48 h. Similar results were obtained when cows grazed pasture on which large amounts of zinc oxide had been sprayed.  相似文献   
152.
From October 1983 to July 1984, the north hemisphere of Venus, from latitude 30 degrees to latitude 90 degrees , was mapped by means of the radar imagers and altimeters of the spacecraft Venera 15 and Venera 16. This report presents the results of the radar mapping of the Maxwell Montes region, one of the most interesting features of Venus' surface. A radar mosaic map and contour map have been compiled.  相似文献   
153.
Of 131 cases of Corynebacterium equi infection in horses submitted for necropsy to the Ontario Veterinary College or Veterinary Laboratory Services, OMAF, Guelph, Ontario from 1958 to 1984, 115 were diagnosed as suppurative pneumonia, and of these 55 had associated ulcerative enterocolitis. Only five animals had intestinal involvement without pulmonary lesions. The remaining 11 cases included arthritis/cellulitis, skin abscesses and submandibular lymphadenitis. While the lung, intestine and associated lymph nodes yielded C. equi most frequently, in 21% of cases C. equi was also cultured from parenchymatous organs (spleen, liver or kidney) or blood. Corynebacterium equi infection accounted for 10% of all foals submitted for postmortem examination and 45% of all foals with pneumonia. Affected foals were one to four months of age. Submissions occurred between the months of May and August with a peak during July. There was a significantly greater prevalence of C. equi infection in Standardbreds when compared with other breeds. Of foals in this study, 36% were from farms which had had other horses succumb to this disease. Of the foals with pulmonary involvement, 21% did not have fever or clinical signs referable to the respiratory or gastrointestinal systems, findings which indicated that a large percentage of cases were subclinical.  相似文献   
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P & P practice     
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156.
The concepts of "host" and "vector" are compared in application to arthropods which are capable to transmit pathogens to man and animals. The paper shows that these concepts are not identical. The function of such arthropods as hosts of microorganisms, as well as their possible importance in population ecology, epidemiology and epizootology are discussed. The system of different concepts corresponding to the tasks of these scientific disciplines is also considered.  相似文献   
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The ocular absorption, elimination and toxicity of 12.5 mg of methotrexate in 0.5 cc administered subconjunctivally was studied in the dog. The purpose of this study was to establish ocular pharmacokinetics for treatment of intraocular tumours in dogs. Drug levels were measured in ocular compartments, and serum at 1,2,4,6,8 and 12 hours respectively. Tumoricidal concentrations of the drug were attained in the anterior chambers of the injected eyes up to and including six hours postinjection. Consistent signs of toxicity were anorexia, vomiting, weight loss and leukopenia. Local ocular toxicity following subconjunctival injection was minimal conjunctival hyperemia lasting up to 48 hours.  相似文献   
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