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11.
As in most parts of the world where the cattle tick Boophilus microplus is established, resistance of ticks to acaricides occurs in New Caledonia. In order to implement laboratory resistance tests on larvae, engorged females collected in suspected farms are necessary. Investigations on the detachment schedule of the engorged females were conducted to explain certain field situations such as the lack or scarcity of engorged females on highly infested cattle driven from the pasture to the pen in the morning. Three experiments on Charolais steers naturally infested on pastures showed that: (1) engorged female burdens at sunrise are similar whether the steers spend the night in pasture or in a pen; (2) compared with steers maintained in a pen, morning detachment of females increases when the steers stay on the pasture or move from the pasture to the pen; (3) detachment rhythm of engorged females on steers staying the morning in a pen, is not influenced by feeding activity or exposition of steers to sun; (4) detachment occurs earlier for females attached on anatomical sites exposed to sun, and earlier from these sites for the steers in pasture or walking than for steers in a pen.  相似文献   
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Results from in vitro studies have indicated that calcium pentosan polysulphate (CaPPS) may be of therapeutic value in osteoarthritis (OA) in the horse. However, no controlled clinical trials using this drug in equine OA have yet been reported. If CaPPS is to be developed for such use, the relationship between the proposed i.m. dose of CaPPS to be used and the concentrations of drug attained in plasma and synovial fluid of the target joint should first be established. An investigation was undertaken to determine these concentrations after a single 2 mg/kg i.m. injection of CaPPS. Blood and synovial fluid samples were taken from 6 healthy, sound horses following i.m. CaPPS administration. Concentrations of CaPPS measured in the synovial fluid were, on the basis of published studies, sufficient to elicit a potential therapeutic effect on synoviocyte metabolism, and possibly also to stimulate proteoglycan synthesis and reduce matrix metalloproteinase activities in articular cartilage. It would therefore seem justified to investigate further the therapeutic effect of CaPPS in OA in the horse.  相似文献   
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The aims of this prospective study were to investigate the associations and correlations between individual clinical features of osteoarthritis of the cruciate deficient stifle joint and to document the temporal changes in these features over a 13-month period following surgical treatment. Fifty-eight dogs with osteoarthritis of the stifle joint, secondary to cranial cruciate ligament deficiency, were examined before surgical treatment for cruciate deficiency and at one and a half, seven and 13 months after surgery. At each visit, clinical features were graded using four-point, discontinuous, ordinal grading (Likert) scales and intra-articular pathology was also scored in a similar fashion at arthrotomy. No attempt was made to construct an aggregate score because the relative importance of different disease features and the relationships between them were not understood at the time of writing. At entry, the relationships between background and disease variables and clinical parameters were investigated as well as the relationships between clinical parameters and intra-articular pathology scores. Longitudinal analysis was performed to test for those features which showed significant change over the 13-month follow-up period. At entry, periarticular thickening and degree of crepitus were significantly correlated with disease duration. Several features showed significant change over the study period. Notably, the degree of quadriceps atrophy showed significant decrease from baseline scores at seven and 13 months while remaining different from normal, suggesting that a measure of quadriceps atrophy may be a useful measure of long-term outcome in this disease.  相似文献   
15.
Gultekin  Atalan  DVM  Frances J.  Barr  MA  VetMB  PhD  MRCVS  Peter E.  Holt  BVMS  PhD  CBiol  MIBiol  FRCVS 《Veterinary radiology & ultrasound》1998,39(5):446-450
The purpose of this study was to determine if ultrasonographic measurement of multiple cross-sectional areas combined with linear dimensions of the bladder could be used as a method of estimating bladder volume in the dog, and, if so, to compare the accuracy of this estimation with that described previously using linear measurements alone. Fifty-two live dogs undergoing investigation for urological disease and 37 fresh canine cadavers were used for bladder volume determination. Maximal length, depth, width, and area were measured from the maximal longitudinal and transverse sonograms in each living animal. In cadavers, the cross-sectional area of the longitudinal section of the bladder was measured at one centimeter intervals, and the measurements were summed. Based on sequential partial regression analysis, the cross-sectional area of the longitudinal section of the bladder and length were the best predictors of actual bladder volume in living animals. However, based on the cadaver experiment, the best predictor of actual bladder volume was summed parasagittal area alone, and, in cadavers, this was a much better predictor of actual bladder volume than the combination of the cross-sectional area of the longitudinal section of the bladder and length. The formula derived in living dogs using the corss-sectional area of the longitudinal section of the bladder and length gave a less accurate estimation of bladder volume than a previously published formula where only linear measurements were used.  相似文献   
16.
A cystic thymoma was identified in an eight-year-old domestic longhair cat with a chronic cough. Radiographs indicated a large mass of soft tissue density in the anterior thorax. Ultrasonography revealed an echogenic mass occupying the cranial and mid-thorax with a slight swirling movement of the echoes. Subsequent drainage under ultrasound guidance yielded a cholesterol-rich fluid. The mass was resected at exploratory thoracotomy and the diagnosis of thymoma confirmed. There was no sign of recurrence one year postoperatively. The clinical features and unusual laboratory findings are presented and compared with previously reported cases of thymomata in the cat.  相似文献   
17.
This series of case reports details observations on toxicity episodes in poultry due to a variety of chemotherapeutic agents. These problems arose owing to overdosage, variation in species susceptibility, potentiation of the toxic effects of one substance by the presence of another substance, and particular disease or other on-farm factors. Ignorance and accident were responsible for some of these situations. The episodes involved monensin, salinomycin, nicarbazin, sulphaquinoxaline, dinitolmide, dimetridazole, nitrofurans, streptomycin, and 3-nitro-4-hydroxyphenylarsonic acid.  相似文献   
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During the period July 1977 to June 1984, specimens from 1402 broiler chicken flocks were submitted to the Veterinary Research Institute, Victoria, Australia for investigation of morbidity, mortality and, or, poor performance. A total of 19,450 post mortem examinations, as well as numerous ancillary tests, were performed. The findings on these flocks are presented and the consequences of some particular diseases noted.  相似文献   
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