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Objective The first national abattoir survey of Cysticercus bovis (‘beef measles’) in cattle was conducted in February 2008. Methods During the data collection period, 493,316 cattle were subjected to standard postmortem procedures, including incision of the masseter and heart muscles. On-site veterinarians were asked to record the location of any C. bovis cysts, as well as the National Livestock Identification System ear tag numbers of infected animals. Veterinarians were asked to submit samples for laboratory confirmation by histology and polymerase chain reaction testing. Results Of the 23 samples submitted, none was positive for C. bovis by either diagnostic method. Conclusions Occasional, isolated diagnoses of beef measles are still made in most states of Australia, but since the last regional surveys were conducted 30 years ago, when the estimated prevalence was 50 to 200 per 100,000 cattle slaughtered, the parasite has become extremely rare.  相似文献   
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An 8‐year‐old Shih Tzu developed abdominal pain and hyperglobulinemia. A round splenic mass was noted radiographically and sonographically. The patient was evaluated by fluorodeoxyglucose positron emission tomography coupled with computed tomography (FDG‐PET/CT). There was no evidence of metastasis or bone marrow involvement on PET/CT images. The standardized uptake value (SUV) of the splenic mass was increased over the reference range (SUV=4.83). The patient was diagnosed as splenic extramedullary plasmacytoma through immunohistopathologic study. After the splenectomy, the globulin level normalized and the patient is alive without complications.  相似文献   
44.
S184 and Grasslands Huia white clover were surface seeded into native Molinia pasture on a wet stagnogley hill soil containing no indigenous Rhizobium trifolii . Seedlings were 'spray inoculated' after emergence with each of five strains of R. trifolii . The two best rhizobial treatments produced a sevenfold increase in seedling establishment followed by nearly fivefold improvement in dry matter production in the following year. There was a strong interaction between Rhizobium strains and plant varieties. Results re-affirm the potential for improving clover performance through inoculation and also demonstrate the need for a better understanding of the factors leading to establishment of successful plant- Rhizobium associations before predictable performance can be achieved in these harsh hill environments.  相似文献   
45.
An enzyme which hydrolyzes the rhamnose from ∞-solanine was isolated and partially purified by ammonium sulfate precipitation from the peels of Kennebec and Wauseon potatoes. Enzyme activity was found to be present in the 60 to 80% ammonium sulfate fraction. Enzyme activity was increased by the use of non-ionic detergents with a mixture of Triton X-100:Triton CF-54 (2:1, w/w) providing the greatest increase in activity. The pH optimum for the rhamnosidase for both varieties was found to be 6.0 while of the temperatures evaluated 42 °C was the optimum temperature. The effect of substrate concentration on enzyme activity was determined for both varieties and the Vmax and Km were calculated from Lineweaver-Burke double reciprocal plots. The Vmax and Km for the Kennebec and Wauseon rhamnosidases were found to be 0.27 mg/ml and 5.4 x 10-4 M and 0.48 mg/ml and 8.2 x 10-4 M, respectively.  相似文献   
46.
The farrowing rates resulting from matings on different days of the week were determined for a 2800-sow intensive piggery in both 1983 and 1984. The results showed that sows mated early in the week achieved a significantly higher farrowing rate than sows mated late in the week (P less than 0.0001). During the seasonal (summer to autumn) infertility period, Wednesday matings resulted in a poor farrowing rate whereas for the rest of the year farrowing rates following Wednesday matings were similar to those for Sunday Monday and Tuesday matings. Consistent results were obtained for data from both years. It is proposed that the stress of regrouping unmated sows on Wednesday to accommodate newly weaned sows is responsible for this decrease in fertility. This study illustrates how detailed analysis of farrowing rates on a day of mating basis can identify a problem which is otherwise masked by weekly data.  相似文献   
47.
The pathogenicity of 2 isolates of each of serovars 7, 3, 1 and 2 of Actinobacillus pleuropneumoniae was tested by intranasal inoculation into 60, 6-week-old large white pigs. Four dose rates varying from 0.27 to 560 x 10(6) organisms per pig with 10-fold serial dilutions were used. Surviving pigs were necropsied 7 days after inoculation. The proportion of pigs dying and developing gross lesions following infection was significantly greater for pigs given serotype 1 than for each of the other 3 serotypes, which did not differ significantly from each other. Twelve of 16 pigs given either of the 2 isolates of serovar 1 died after acute illness and 1 of 44 pigs given either of the 2 isolates each of serovars 7, 3 and 2 died. Pigs given serovar 1 showed high temperatures, severe respiratory distress, frothy haemorrhagic nasal discharge and weight loss. Lung lesions were produced in all 16 pigs given serovar 1, in 7 of 14 pigs given serovar 7, 7 of 14 pigs receiving serovar 3 and in 5 of 16 pigs given serovar 2. The lethal infections were characterised by a severe acute fibrinohaemorrhagic necrotising pleuropneumonia, whereas non-lethal cases had lung lesions ranging from necrotising purulent pleuropneumonia to abscessation. Significant differences between isolates in proportions of tissues culture positive for A. pleuropneumoniae for serovars 7 and 2, but not for serovars 3 and 1 suggested that isolates may vary in virulence within serovars, but more detailed studies are needed to clarify this point.  相似文献   
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The acute toxicity for sheep of 3 alkaloids that occur in Phalaris acquatica was examined by intravenous and oral administration. The lowest tested dose rates that produced clinically observed signs were, for 5-methoxy dimethyltryptamine, 0.1 mg/kg body weight intravenously and 40 mg/kg orally; for gramine, 10 mg/kg intravenously and 500 mg/kg orally; and for hordenine, 20 mg/kg intravenously and 800 mg/kg orally. All induced the clinical signs observed in the nervous form of phalaris toxicity, but none induced the cardiac, sudden death, syndrome.  相似文献   
50.
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