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941.
942.
The complement fixation test (CFT), the enzyme labelled immunosorbent assay (ELISA) and the gel diffusion precipitin test (GD) were compared, for the diagnosis of Brucella ovis infection in rams. The sensitivities of the tests in 109 rams which were shedding B. ovis in their semen were: CFT 96.3%; ELISA 97.2%; GD 91.7%. The specificities of the tests in 141 rams from non-infected flocks were: CFI 99.3%; ELISA 98.6%; GD 100%. Predictive values of the three tests were measured in 285 rams from infected flocks. Thirty-eight percent of these rams were shedding B. ovis in their semen. Predictive values of positive tests were: CFT 75.5%; ELISA 66.7%; GD 72.5%. Predictive values of negative tests were: CFI 97.1%; ELISA 97.6%; GD 93.8%. 相似文献
943.
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
944.
Two lactational intramammary antibiotic preparations (cloxacillin and oxytetracycline) were each used to treat eight goats by intramammary infusion in one half. The rate of release of the antibiotics was monitored by a diffusion assay based on the sensitive organism Bacillus stearothermophilus var. calidolactis. Cloxacillin was still detectable 156 hours after the final treatment while oxytetracycline was undetectable 108 hours following treatment. A small but significant amount of antibiotic was translocated between treated and untreated halves of the udder in both cases. 相似文献
945.
A study of the interaction between bromocresol green dye and bovine,ovine and equine serum globulins
In human medicine it has been shown that the bromocresol green (BCG) dye-binding method for the determination of serum albumin is not entirely specific, the dye reacting also with certain human serum globulins. This causes over-estimation of albumin when reaction times are prolonged beyond 30 seconds.In the present study, serum albumin values obtained from three animal species by the immediate, i.e. less than 30 seconds, BCG reaction were compared with those by the 10-minute BCG reaction. Albumin-depleted sera were prepared using an affinity chromatography technique and their reactions and those of purified gamma globulin preparations with the dye were studied.In cattle, sheep and horses, serum albumin values obtained by the 10-minute reaction were higher than those obtained by the immediate BCG reaction, the differences being statistically significant. Purified gamma globulin did not react with the BCG dye after 10 minutes, but other globulins did. There were differences between the species in the magnitude of the reaction of their globulins with BCG dye. 相似文献
946.
Hirsch VM Mitcham SC Dunn DK 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1984,13(2):16-20
An unusual combination of blood cytopenias and monocytic proliferation was observed in a dog. Initial hematologic findings included severe thrombocytopenia, neutropenia, mild nonregenerative anemia and apparently normal bone marrow. Subsequently, a severe persistent monocytosis developed and the bone marrow became populated with monocytes and cytophagic macrophages. Splenomegaly was due to reticuloendothelial hyperplasia and extramedultary hematopoiesis. Treatment consisted of splenectomy and azathioprine but the response was poor and the dog was euthanized. Postmortem examination revealed a hypocellular bone marrow which contained moderate numbers of monocytes and plasma cells. Neoplastic proliferation was absent in visceral organs. No definite diagnosis was established; chronic blood cell consumption, perhaps immune-mediated, may have been responsible for the extensive reticuloendothelial hyperplasia and cytophagia. 相似文献
947.
The cleistogamous species Collomia grandiflora produces dimorphic cross-incompatible flowers on a single plant. The open or chasmogamous flower has smaller, flask-shaped stigmatic papillae, larger pollen grains, longer styles, and faster pollen tube growth rates down the style than the closed or cleistogamous flower. In intermorph crosses, pollen tube growth rates are greatly decreased and fertilization does not occur. 相似文献
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