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1.
Between January 1985 and May 1989, 53 Thoroughbred horses (mean age 3.2 years) were surgically treated for dorsal cortical fractures of the third metacarpal bone (MC III). All horses were treated with cortical drilling through the fracture line (osteostixis). Diagnosis of the fractures was confirmed by xeroradiography. Lifetime racing records were obtained for all horses. Forty-seven horses returned to racing after surgery (89%). The mean time between surgery and the first race was 6.8 months. Horses had a mean of 10.9 starts before surgery and 16.1 starts after surgery. The mean earnings per start before surgery was $6,459 and after surgery was $5,685. Of the 47 horses that raced after surgery, 70% raced at the same class or improved. Complications related to surgery were seen in 10 horses. Two horses had a second fracture of MC III at the same site, and were again treated by osteostixis, after which both horses returned to competition. Fractured drill bits were left in the MC III of 4 horses. One of these horses had catastrophic failure of MC III. Two horses developed subcutaneous infections and 2 horses had catastrophic failure of MC III in the surgically treated limb. Osteostixis appears to be an effective treatment for returning horses affected with dorsal cortical fractures to racing.  相似文献   
2.
The examination of the foot must be based on observations of the hoof, followed by a careful determination of areas of pain. This must be followed by an assessment of the biomechanical forces on the hoof and limb. Finally, imaging gives insight into the nature of the injury and allows the examiner to prognosticate the outcome.  相似文献   
3.
This article reviews recent diagnostic procedures that have arisen over the last 10 years. Videoendoscopy of horses on a high-speed treadmill allows observation of some of the changes that take place in a horse's airway during exercise. Measurements of upper airway airflows and transupper airway pressure, the use of an esophageal balloon and a Ventigraph to measure changes in pleural pressure, and pulmonary function testing are new techniques that aid the researcher in understanding the mechanics and pathologic characteristics of airway diseases and help the practitioner in assessing the severity of a problem, measuring response to therapy, and accurately determining a prognosis.  相似文献   
4.
Tetracycline, metronidazole, and chlorhexidine have been tested for their effectiveness in the treatment of periodontitis in dogs under experimental conditions. Tetracycline has been effective in reducing bone resorption in dogs with periodontitis when used in the long-term. When used for short times, it can result in reduction of the numbers of microorganisms that are associated with disease. Tetracycline can inhibit the activity of mammalian collagenase thought responsible for the destruction of alveolar bone and it may be capable of inhibiting the adherence of microorganisms and thus preventing infection. In some experiments, metronidazole was more effective than tetracycline in eliminating spirochetes from the periodontal flora, and it has been found effective in preventing the inflammation and the development of the bacterial flora usually associated with the natural accumulation of plaque. Chlorhexidine (0.2% aqueous solution) has been found effective in preventing the normal progression of periodontal disease when used as a spray for the long-term treatment of dogs. It could prove to be as effective as brushing for the long-term control of periodontitis in the dog. Limited information is available on the use of clindamycin, spiramycin, and vancomycin.  相似文献   
5.
A herpesvirus and cytopathogenic bovine viral diarrhea virus were isolated from a bovine fetus aborted in the 6th month of gestation. The herpesvirus was serologically indistinguishable from bovine herpesviruses DN-599 and Movar 33/63.  相似文献   
6.
Experimental infection of eastern cottontail rabbits (Sylvilagus floridanus) with infectious bovine rhinotracheitis virus caused acute keratoconjunctivitis and a fatal systemic infection. The clinical syndrome was characterized initially by blepharospasm and ocular discharge. The rabbits were markedly depressed on post-exposure day (PED) 5 and were dead or moribund on PED 6. The virus was readily recovered from liver and adrenal gland tissue on PED 6 and from conjunctival swabs on PED 1 to 6. Histopathologic studies revealed a few necrotic foci in the liver and multiple focal to diffuse necrosis of the adrenal glands. Viral isolation and immunofluorescence tests were used to demonstrate a direct association between infectious bovine rhinotracheitis viral antigens and the lesions.  相似文献   
7.
Bovine adenovirus type 7 was isolated from a 10-month-old calf with fibrinopurulent pneumonia and from 2 newborn calves with pneumoenteritis. The viruses were isolated on calf lung and adrenal gland cell cultures and were identified as serotype 7 by immunoelectron microscopy and serum-neutralization tests.  相似文献   
8.
9.
We examined hunters’ perceptions of fauna to see if expert hunters and other hunters perceive wildlife abundance similarly. We used cultural consensus analysis (CCA) to assess the knowledge of 25 hunters in the Bolivian Amazon about the abundance of 38 animals. CCA indicated highly shared beliefs among hunters concerning wildlife abundance (average agreement = .62). However, expert hunters (as judged by their reported successful hunts of rare species, having hunted recently, and consuming more game in their diet) perceived more animals as abundant than did non-experts, although they all shared the same model. Since the expert hunters did not always agree on which species was more abundant, they had low cultural knowledge scores in CCA results. These experts may be unwilling to curtail hunting efforts on key species that they perceive to be abundant.  相似文献   
10.
Participation in conservation programs is often viewed as a necessity, but understanding of this participation is limited. This research takes a different approach by also examining participation in non-conservation-related activities. Questionnaires (N = 339) were administered in four Brazilian coastal communities where the national sea turtle conservation project conducts monitoring and outreach. Employing social capital as a conceptual framework, measurements included participation in civic, community, and social activities along with group participation and collective action. Confirmatory factor analysis was used for validating measures of social capital and conservation perceptions. Structural equation modeling indicated that social capital has a positive relationship with participation in sea turtle conservation, suggesting that general levels of participation and community norms of participation could be just as influential as conservation perceptions to engage communities in conservation. Information gained by deconstructing participation may be used to design and target conservation programs, improving overall participation.  相似文献   
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