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71.
OBJECTIVE: To evaluate the efficacy of a commercially available killed bovine viral diarrhea virus (BVDV) vaccine to protect against fetal infection in pregnant cattle continually exposed to cattle persistently infected with the BVDV. ANIMALS: 60 crossbred beef heifers and 4 cows persistently infected with BVDV. PROCEDURES: Beef heifers were allocated to 2 groups. One group was vaccinated twice (21-day interval between the initial and booster vaccinations) with a commercially available vaccine against BVDV, and the other group served as nonvaccinated control cattle. Estrus was induced, and the heifers were bred. Pregnancy was confirmed by transrectal palpation. Four cows persistently infected with BVDV were housed with 30 pregnant heifers (15 each from the vaccinated and nonvaccinated groups) from day 52 to 150 of gestation. Fetuses were then harvested by cesarean section and tested for evidence of BVDV infection. RESULTS: 1 control heifer aborted after introduction of the persistently infected cows. Bovine viral diarrhea virus was isolated from 14 of 14 fetuses obtained via cesarean section from control heifers but from only 4 of 15 fetuses obtained via cesarean section from vaccinated heifers; these proportions differed significantly. CONCLUSIONS AND CLINICAL RELEVANCE: A commercially available multivalent vaccine containing an inactivated BVDV fraction significantly reduced the risk of fetal infection with BVDV in heifers continually exposed to cattle persistently infected with BVDV. However, not all vaccinated cattle were protected, which emphasizes the need for biosecurity measures and elimination of cattle persistently infected with BVDV in addition to vaccination within a herd.  相似文献   
72.
OBJECTIVE: To compare veterinarians' and pet owners' perceptions of client expectations with respect to the monetary aspects of veterinary care and identify challenges encountered by veterinarians in dealing with pet owners' expectations. DESIGN: Qualitative study based on focus group interviews. PARTICIPANTS: 6 pet owner focus groups (32 owners) and 4 veterinarian focus groups (24 companion animal veterinarians). PROCEDURES: Independent focus group sessions were conducted with standardized open-ended questions and follow-up probes. Content analysis was performed on the focus group discussions. RESULTS: Pet owners expected the care of their animal to take precedence over monetary aspects. They also expected veterinarians to initiate discussions of costs upfront but indicated that such discussions were uncommon. Veterinarians and pet owners differed in the way they related to discussions of veterinary costs. Veterinarians focused on tangibles, such as time and services. Pet owners focused on outcome as it related to their pet's health and well-being. Veterinarians reported that they sometimes felt undervalued for their efforts. A suspicion regarding the motivation behind veterinarians' recommendations surfaced among some participating pet owners. CONCLUSIONS: Results suggested that the monetary aspects of veterinary care pose barriers and challenges for veterinarians and pet owners. By exploring clients' expectations, improving communication, educating clients, and making discussions of cost more common, veterinarians may be able to alleviate some of the monetary challenges involved in veterinarian-client-patient interactions.  相似文献   
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Social media is an increasingly common form of communication, with Facebook being the preferred social-networking site among post-secondary students. Numerous studies suggest post-secondary students practice high self-disclosure on Facebook. Research evaluating veterinary students' use of social media found a notable proportion of student-posted content deemed inappropriate. Lack of discretion in posting content can have significant repercussions for aspiring veterinary professionals, their college of study, and the veterinary profession they represent. Veterinarians-in-training at three veterinary colleges across Canada were surveyed to explore their use of and attitude toward the social networking site, Facebook. Students were invited to complete an online survey with questions relating to their knowledge of privacy in relation to using Facebook, their views on the acceptability of posting certain types of information, and their level of professional accountability online. Linear regression modeling was used to further examine factors related to veterinary students' disclosure of personal information on Facebook. Need for popularity (p<.01) and awareness of consequences (p<.001) were found to be positively and negatively associated, respectively, with students' personal disclosure of information on Facebook. Understanding veterinary students' use of and attitudes toward social media, such as Facebook, reveals a need, and provides a basis, for developing educational programs to address online professionalism. Educators and administrators at veterinary schools may use this information to assist in developing veterinary curricula that addresses the escalating issue of online professionalism.  相似文献   
75.
Elective ovariohysterectomy was performed on 66 cats. Surgical approach was flank (group F) or midline (group M) allocated by block randomisation. Pre-anaesthetic medication was acepromazine (0.1 mg/kg) via intramuscular injection. Anaesthesia was induced with intravenous thiopentone, and maintained with halothane in 100% oxygen. Carprofen (4 mg/kg) was administered by the subcutaneous route immediately after induction of anaesthesia. Postoperative pain and wound tenderness were assessed at 1, 3, 6, 9, 11-12 and 20-24h after the end of surgery, and the assessment outcome marked on visual analogue scales (VAS). Intervention analgesia (if pain VAS was >40 mm) was pethidine 4 mg/kg via intramuscular injection. Area under the curve (AUC) for VAS for pain and VAS for wound tenderness for each cat were calculated. AUC for wound tenderness was significantly greater for group F (P = 0.007). There was no significant difference for AUC for pain between the groups. In conclusion, wounds after flank ovariohysterectomy are significantly more tender than after midline ovariohysterectomy in the cat. This indicates that interactive methods, including wound palpation, must be used to assess postoperative pain and the findings should be appropriately weighted in the overall assessment.  相似文献   
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77.
Facebook has been identified as the preferred social networking site among postsecondary students. Repeated findings in the social networking literature have suggested that postsecondary students practice high personal self-disclosure on Facebook and tend not to use privacy settings that would limit public access. This study identified and reviewed Facebook profiles for 805 veterinarians-in-training enrolled at four veterinary colleges across Canada. Of these, 265 (32.9%) were categorized as having low exposure, 286 (35.5%) were categorized as having medium exposure, and 254 (31.6%) were categorized as having high exposure of information. Content analysis on a sub-sample (n=80) of the high-exposure profiles revealed publicly available unprofessional content, including indications of substance use and abuse, obscene comments, and breaches of client confidentiality. Regression analysis revealed that an increasing number of years to graduation and having a publicly visible wall were both positively associated with having a high-exposure profile. Given the rapid uptake of social media in recent years, veterinary educators should be aware of and begin to educate students on the associated risks and repercussions of blurring one's private life and one's emerging professional identity through personal online disclosures.  相似文献   
78.
The administration of a 50% (w/v) zinc sulphate solution by drenching gun to lactating dairy cows (30 mg Zn/kg/d) during the spore ingestion phase of a mild natural facial eczema outbreak had a marked prophylactic effect as judged by serum gamma-glutamyl transferase values. Weight changes recorded over the period of the experiment indicated that the zinc doses may also have caused inappetance or marginal toxicity under the conditions of the experiment.  相似文献   
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80.
Global consequences of land use   总被引:83,自引:0,他引:83  
Land use has generally been considered a local environmental issue, but it is becoming a force of global importance. Worldwide changes to forests, farmlands, waterways, and air are being driven by the need to provide food, fiber, water, and shelter to more than six billion people. Global croplands, pastures, plantations, and urban areas have expanded in recent decades, accompanied by large increases in energy, water, and fertilizer consumption, along with considerable losses of biodiversity. Such changes in land use have enabled humans to appropriate an increasing share of the planet's resources, but they also potentially undermine the capacity of ecosystems to sustain food production, maintain freshwater and forest resources, regulate climate and air quality, and ameliorate infectious diseases. We face the challenge of managing trade-offs between immediate human needs and maintaining the capacity of the biosphere to provide goods and services in the long term.  相似文献   
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