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81.
Ultrasonographic findings of splenic infarction and necrosis in three dogs are presented. Two previously unreported ultrasonographic patterns are identified: (1) Focal, hypoechoic or isoechoic, circular, wellmarginated nodular masses with peripheral lesions causing deformation of the splenic margin. (2) Diffuse hypoechoic or heteroechoic coarse/"lacy" parenchymal pattern with no deformation of margin. The presence of gas within the splenic parenchyma of one dog was detected by both radiography and ultrasonography. Ultrasonographic patterns of splenic infarction in both man and the dog are discussed  相似文献   
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Of 100 critically ill dogs and cats, 49 (39 dogs, 10 cats) had bacteremia. Gram-negative bacilli were the most common isolates from the bloodstream of dogs with bacteremia (46%), and gram-positive cocci and anaerobic bacteria were isolated from 36% and 31% of positive cultures, respectively; 15% of positive cultures were polymicrobial. In cats, gram-negative bacilli (especially Salmonella enteritidis) and anaerobic bacteria were the most common isolates, and 30% of positive cultures were polymicrobial. Gram-positive cocci were not isolated from the blood-stream of cats. Odds ratios, adjusted for the combined effects of disease status (severe vs nonsevere), results of bacterial culture of blood result (positive vs negative), and species (dog vs cat) were calculated for mortality in animals in the study. In animals with bacteremia, severe disease increased the risk of death 11.6-fold, compared with the risk in animals with nonsevere disease. Bacteremia increased mortality 10-fold in animals with severe disease, compared with mortality in animals with severe disease without bacteremia. Animals with severe disease and bacteremia were 15.6 times more likely to die than were those with nonsevere disease and negative culture results. In animals with nonsevere disease, culture results (positive vs negative) were not related significantly to mortality. Disease status (severe vs nonsevere) in animals without bacteremia also was not significantly related to mortality. There was no significant difference in overall mortality in dogs, compared with that in cats.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
84.
Abstract   For a number of reasons, several of the more 'traditional' ectoparasiticides in the small animal veterinarian's armoury have been withdrawn over the past few years. New, safer products which are long-acting and easier to apply than the conventional dips, rinses and aerosol sprays of the past have replaced them. However, relatively few such novel acaricidal preparations have become commercially available. Consequently, practitioners and researchers frequently experiment with the drugs they have at their disposal to assess their efficacy against a variety of target acarids when used at different dosages and/or via different routes of administration, compared with those recommended by the manufacturer. This paper reviews the anecdotal and peer-reviewed reports describing the use of modern acaricides in dogs and cats that have recently appeared in the veterinary literature. It should be stressed, however, that no medicine should be prescribed for extra-label use without the informed consent of the owner.  相似文献   
85.
RNA viruses infect marine organisms from bacteria to whales, but RNA virus communities in the sea remain essentially unknown. Reverse-transcribed whole-genome shotgun sequencing was used to characterize the diversity of uncultivated marine RNA virus assemblages. A diverse assemblage of RNA viruses, including a broad group of marine picorna-like viruses, and distant relatives of viruses infecting arthropods and higher plants were found. Communities were dominated by distinct genotypes with small genome sizes, and we completely assembled the genomes of several hitherto undiscovered viruses. Our results show that the oceans are a reservoir of previously unknown RNA viruses.  相似文献   
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Extract

Under intensified management systems, the more common diseases of beef cattle include pasteurellosis or shipping fever, infectious bovine rhinotracheitis (IBR), enzootic or virus pneumonia, and bovine diphtheria. Other respiratory diseases that might be prevalent in the beef management systems of New Zealand include lungworm, atypical interstitial pneumonia, and allergic rhinitis. These will be discussed only in terms of differential diagnosis. No further mention will be made of the exotic diseases contagious bovine pleuropneumonia and haemorrhagic septicaemia or to the respiratory form of bovine tuberculosis which is uncommon in both Canada and New Zealand.  相似文献   
88.
Rapid ?ōhi?a Death (ROD) is a fungal disease of ?ōhi?a lehua (Myrtaceae: Metrosideros polymorpha) caused by Ceratocystis lukuohia and C. huliohia. ROD is the aetiological agent of widespread mortality of this important tree on Hawai?i Island, but its epidemiology remains unclear. We investigated the prevalence and viability of C. lukuohia in ambrosia beetle frass in ROD‐affected ?ōhi?a trees. A total of 200 frass traps were placed onto C. lukuohia‐infected ?ōhi?a at four locations on the east side of Hawai?i Island. Frass was collected and screened for the presence of C. lukuohia DNA using a diagnostic qPCR assay. In addition, frass samples were screened for viability by carrot baiting. All trapped beetles were of the genus Xyleborus, with the majority being the non‐native X. ferrugineus. Of the frass samples tested, 62% contained C. lukuohia DNA and 17% of carrot baits were positive for the fungus. These results indicate that ambrosia beetle frass releases C. lukuohia into the environment. We discuss the potential role infested frass could play in the ROD pathosystem.  相似文献   
89.
OBJECTIVE: To assess pharmacokinetics, efficacy, and tolerability of oral levetiracetam administered as an adjunct to phenobarbital treatment in cats with poorly controlled suspected idiopathic epilepsy. DESIGN-Open-label, noncomparative clinical trial. ANIMALS: 12 cats suspected to have idiopathic epilepsy that was poorly controlled with phenobarbital or that had unacceptable adverse effects when treated with phenobarbital. PROCEDURES: Cats were treated with levetiracetam (20 mg/kg [9.1 mg/lb], PO, q 8 h). After a minimum of 1 week of treatment, serum levetiracetam concentrations were measured before and 2, 4, and 6 hours after drug administration, and maximum and minimum serum concentrations and elimination half-life were calculated. Seizure frequencies before and after initiation of levetiracetam treatment were compared, and adverse effects were recorded. RESULTS: Median maximum serum levetiracetam concentration was 25.5 microg/mL, median minimum serum levetiracetam concentration was 8.3 microg/mL, and median elimination half-life was 2.9 hours. Median seizure frequency prior to treatment with levetiracetam (2.1 seizures/mo) was significantly higher than median seizure frequency after initiation of levetiracetam treatment (0.42 seizures/mo), and 7 of 10 cats were classified as having responded to levetiracetam treatment (ie, reduction in seizure frequency of >or=50%). Two cats had transient lethargy and inappetence. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that levetiracetam is well tolerated in cats and may be useful as an adjunct to phenobarbital treatment in cats with idiopathic epilepsy.  相似文献   
90.
In a 2-yr study, we evaluated the effect of different forage allocations on the performance of lactating beef cows and their calves grazing stockpiled tall fescue. Allocations of stockpiled tall fescue at 2.25, 3.00, 3.75, and 4.50% of cow-calf pair BW/d were set as experimental treatments. Conventional hay-feeding was also evaluated as a comparison to grazing stockpiled tall fescue. The experiment had a randomized complete block design with 3 replications and was divided into 3 phases each year. From early December to late February (phase 1) of each year, cows and calves grazed stockpiled tall fescue or were fed hay in the treatments described above. Immediately after phase 1, cows and calves were commingled and managed as a single group until weaning in April (phase 2) so that residual effects could be documented. Residual effects on cows were measured after the calves were weaned in April until mid-July (phase 3). During phase 1 of both years, apparent DMI of cow-calf pairs allocated stockpiled tall fescue at 4.50% of BW/d was 31% greater (P < 0.01) than those allocated 2.25% of BW/d. As allocation of stockpiled tall fescue increased from 2.25 to 4.50% of cow-calf BW/d, pasture utilization fell (P < 0.01) from 84 +/- 7% to 59 +/- 7%. During phase 1 of both years, cow BW losses increased linearly (P < 0.02) as forage allocations decreased, although the losses in yr 1 were almost double (P < 0.01) those in yr 2. During phases 2 and 3, few differences were noted across treatment groups, such that by the end of phase 3, cow BW in all treatments did not differ either year (P > 0.40). Calf ADG in phase 1 increased linearly (P < 0.01) with forage allocation (y = 0.063x + 0.513; R(2) = 0.91). However, calf gain per hectare decreased linearly (P < 0.01) as stockpiled tall fescue allocations increased (y = -26.5x + 212; R(2) = 0.97) such that gain per hectare for cow-calf pairs allocated stockpiled tall fescue at 4.50% BW/d was nearly 40% less (P < 0.01) than for those allocated 2.25% of BW/d. Allocating cow-calf pairs stockpiled tall fescue at 2.25% of BW/d likely optimizes its use; because cow body condition is easily regained in the subsequent spring and summer months, less forage is used during winter, and calf gain per hectare is maximized.  相似文献   
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