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861.
Reasons for performing the study: Removal of large chip fractures of the carpal bones and the osteochondral deficits that result, have been associated with a worse prognosis than removal of small fragments in similar locations. Hypothesis: Reducing the articular defects by repair of large osteochondral fragments may have advantages over removal. Methods: Horses with osteochondral chip fractures that were of sufficient size and infrastructure to be repaired with small (2.7 mm diameter) AO/ASIF cortex screws were identified and repair effected by arthroscopically guided internal fixation. Results: Thirty‐three horses underwent surgery to repair 35 fractures of the dorsodistal radial carpal bone (n = 25), the dorsal margin of the radial facet of the third carpal bone (n = 9) and the intermediate facet of the distal radius (n = 1). There were no surgical complications and fractures healed satisfactorily in 26 of 28 horses and 23 horses returned to racing performance. Conclusion: Arthroscopically guided repair of carpal chip fractures with small diameter cortex screws is technically feasible and experiences with 33 cases suggest that this may have advantages over fragment removal in managing such cases. Potential relevance: Surgeons treating horses with large chip fractures of the carpal bones should consider arthroscopically guided internal fixation as an alternative to removal.  相似文献   
862.
863.
Testing all the cattle in an entire state with a uniform procedure for each animal affords an opportunity to relate human injury data to a known number of animals handled while carrying out a standardized procedure. Our objective was to describe the type and incidence density of injuries associated with TB-testing a large number of cattle herds, and to delineate the various factors associated with the risk of injury. A survey was mailed to all veterinarians (N = 259) who had completed at least five official bovine TB (bTB) herd tests in Michigan in 2001. We collected data regarding basic demographics and health status, work experience, veterinary specialty, and practice information. Each veterinarian was also requested to complete a separate injury questionnaire for each injury received while TB testing livestock in 2001. Accurate addresses were found for 247 eligible veterinarians, 175 (71%) of whom returned the survey. Thirty-six veterinarians reported a total of 53 injuries (10 major, 12 minor and 31 self-treated). Hands (29%) and legs (21%) were the anatomic locations most frequently injured, with sprains/strains (30%) and abrasion/contusion (30%) the most common types of injuries sustained. The overall incidence density of injuries was 1.9 per 10,000 animals tested. Female gender (RR = 3.3), being employed by the government (RR = 4.5), and smoking (RR = 6.0) were significantly associated with a higher rate of injury. Significant colliniearities were found between some risk factors associated with an increased rate of injury and participants thought 81% of their injuries could have been prevented. These results are explained by the administrative structure of the bTB testing program in Michigan, and the changing demographics of the veterinary workforce.  相似文献   
864.
865.
866.
The development of methods to produce embryos in vitro in the horse has been delayed compared with other domestic species. Oocytes can be collected from excised ovaries or from the small or preovulatory follicles of live mares. Intracytoplasmic sperm injection is the only reliable method to fertilize equine oocytes in vitro. Intracytoplasmic sperm injection-produced embryos can be transferred into the oviducts of recipient mares or cultured to the morula or blastocyst stage of development for nonsurgical embryo transfers into recipients' uteri. Embryos cultured in vitro have some morphological differences compared with embryos collected from the mares' uteri. Most notably, the embryonic capsule does not form in culture, and the zona pellucida fails to expand completely. However, embryo produced in vitro can result in viable pregnancies and healthy offspring.  相似文献   
867.
Characteristics of free-roaming cats and their caretakers   总被引:1,自引:0,他引:1  
OBJECTIVES: To describe the characteristics of unowned, free-roaming cats and their caretakers who participated in a trap-neuter-return (TNR) program and to determine the effect of the program on free-roaming cat colonies. DESIGN: Prospective study. SAMPLE POPULATION: 101 caretakers of 920 unowned, free-roaming cats in 132 colonies in north central Florida. RESULTS: Most (85/101; 84%) caretakers were female. The median age was 45 years (range, 19 to 74 years). Most (89/101; 88%) caretakers owned pets and of those, most (67/101; 66%) owned cats. The major reasons for feeding free-roaming cats were sympathy and love of animals. Most caretakers reported that the cats they cared for were too wild to be adopted, but many also reported that they considered the cats to be like pets. The total surveyed cat population was 920 before participation in TNR and 678 after TNR. Mean colony size was 7 cats before TNR and 5.1 cats after TNR. Most cats lived on the caretaker's property. At the time of the survey, 70% (644/920) of the cats had been neutered. CONCLUSIONS AND CLINICAL RELEVANCE: The decrease in the surveyed free-roaming cat population was attributed to a reduction in births of new kittens, adoptions, deaths, and disappearances. Recognition of the human-animal bond that exists between caretakers and the feral cats they feed may facilitate the development of effective control programs for feral cat populations.  相似文献   
868.
The results of a series of experiments to investigate the use of the arylmethane dye, malachite green, for the control of proliferative kidney disease in rainbow trout (Salmo gairdneri Richardson) are described. Under field conditions using the bath application method the dye gave good control of the disease with treatments at 1.6 ppm for 40 minutes repeated at seven, 14 and 21 day intervals. Flush treatments were also successful using the same treatment intervals and beginning with 3.2 ppm malachite green. The problems of toxicity and of standardising the exposure of the fish to the dye with flush treatments are discussed.  相似文献   
869.
Roundworms and flatworms that affect donkeys can cause disease. All common helminth parasites that affect horses also infect donkeys, so animals that co‐graze can act as a source of infection for either species. Of the gastrointestinal nematodes, those belonging to the cyathostomin (small strongyle) group are the most problematic in UK donkeys. Most grazing animals are exposed to these parasites and some animals will be infected all of their lives. Control is threatened by anthelmintic resistance: resistance to all 3 available anthelmintic classes has now been recorded in UK donkeys. The lungworm, Dictyocaulus arnfieldi, is also problematical, particularly when donkeys co‐graze with horses. Mature horses are not permissive hosts to the full life cycle of this parasite, but develop clinical signs on infection. In contrast, donkeys are permissive hosts without displaying overt clinical signs and act as a source of infection to co‐grazing horses. Donkeys are also susceptible to the fluke, Fasciola hepatica. This flatworm can be transmitted, via snails and the environment, from ruminants. As with cyathostomins, anthelmintic resistance is increasing in fluke populations in the UK. A number of the anthelmintic products available for horses do not have a licence for use in donkeys, and this complicates the design of parasite control programmes. As no new equine anthelmintic classes appear to be near market, it is important that the efficacy of currently effective drugs is maintained. It is important that strategies are used that attempt to preserve anthelmintic efficacy. These strategies should be based on the concept that the proportion of worms in a population not exposed to anthelmintic at each treatment act as a source of ‘refugia’. The latter is an important factor in the rate at which resistance develops. Thus, it is imperative that parasite control programmes take into account the need to balance therapy to control helminth‐associated disease with the requirement to preserve anthelmintic effectiveness.  相似文献   
870.
Species ranked within the genus Baylisascaris (Ascaridida, Ascarididae) have been implicated in clinical and subclinical intestinal diseases in their natural hosts (e.g., raccoons and bears) as well as in life-threatening larva migrans syndromes in a number of incidental hosts, including humans. Following the diagnosis of Baylisascaris transfuga infestation in two captive polar bears, living in the zoo park of Pistoia (Tuscany, Italy), nematodes (n=300; both sexes) have been characterized by morphological and molecular methods by sequencing and analysing ribosomal (large ribosomal DNA (28S) and internal transcribed spacer region 1 and 2 (ITSs)) and mitochondrial (cytochrome c oxidase subunit 1 (cox1) and cytochrome c oxidase subunit 2 (cox2)) target regions. In addition, seven faecal samples were collected from the animal enclosure and submitted to copromicroscopic and molecular examination. All nematodes were morphologically identified as B. transfuga and their main distinctive features are here presented. No variation in size and nucleotide polymorphisms was detected within each target sequence among all samples analysed. These data contribute to facilitate an accurate diagnosis of this little known nematode infestation in order to apply appropriate anthelmintic strategies.  相似文献   
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