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131.
Forty dog-faced fruit bats (Cynopterus brachyotis) were administered 1 drop of 1% ivermectin topically as part of a routine physical exam and deworming program, and 11 developed sudden generalized paresis. Six of the bats recovered within 24-48 hr, and the remaining 5 were presented recumbent and weak to the University of Florida Veterinary Medical Teaching Hospital. Ivermectin toxicosis was suspected, and the admitted bats died or were euthanatized within 3-5 days of the development of clinical signs despite supportive care. Three of the dead bats had renal tubular necrosis.  相似文献   
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OBJECTIVE: To compare plasma disposition of the R(-) and S(+) enantiomers of carprofen after IV administration of a bolus dose to donkeys and horses. ANIMALS: 5 clinically normal donkeys and 3 clinically normal horses. PROCEDURE: Blood samples were collected from all animals at time 0 (before) and at 10, 15, 20, 30, and 45 minutes and 1, 1.5, 2, 2.5, 3, 4, 5, 6, 8, 10, 24, 28, 32, and 48 hours after IV administration of a bolus of carprofen (0.7 mg/kg). Plasma was analyzed in triplicate via high-performance liquid chromatography to determine the concentrations of the carprofen enantiomers. A plasma concentrationtime curve for each donkey and horse was analyzed separately to estimate noncompartmental pharmacokinetic variables. RESULTS: In donkeys and horses, the area under the plasma concentration versus time curve (AUC) was greater for the R(-) carprofen enantiomer than it was for the S(+) carprofen enantiomer. For the R(-) carprofen enantiomer, the AUC and mean residence time (MRT) were significantly less and total body clearance (CIT) was significantly greater in horses, compared with donkeys. For the S(+) carprofen enantiomer, AUC and MRT were significantly less and CIT and apparent volume of distribution at steady state were significantly greater in horses, compared with donkeys. CONCLUSIONS AND CLINICAL RELEVANCE: Results have suggested that the dosing intervals for carprofen that are used in horses may not be appropriate for use in donkeys.  相似文献   
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OBJECTIVE: To determine the biocontainment, biosecurity, and security practices at beef feedyards in the Central Plains of the United States. DESIGN: Survey. SAMPLE POPULATION: Managers of feedyards in Colorado, Kansas, Nebraska, Oklahoma, and Texas that feed beef cattle for finish before slaughter; feedyards had to have an active concentrated animal feeding operation permit with a 1-time capacity of >or= 1,000 cattle. PROCEDURES: A voluntary survey of feedyard personnel was conducted. Identified feedyard personnel were interviewed and responses regarding facility design, security, employees, disease preparedness, feedstuffs, hospital or treatment systems, sanitation, cattle sources, handling of sick cattle, and disposal of carcasses were collected in a database questionnaire. RESULTS: The survey was conducted for 106 feedyards with a 1-time capacity that ranged from 1,300 to 125,000 cattle. Feedyards in general did not have high implementation of biocontainment, biosecurity, or security practices. Smaller feedyards were, in general, less likely to use good practices than were larger feedyards. CONCLUSIONS AND CLINICAL RELEVANCE: Results of the survey provided standard practices for biocontainment, biosecurity, and security in feedyards located in Central Plains states. Information gained from the survey results can be used by consulting veterinarians and feedyard managers as a basis for discussion and to target training efforts.  相似文献   
134.

Context

Scale is the lens that focuses ecological relationships. Organisms select habitat at multiple hierarchical levels and at different spatial and/or temporal scales within each level. Failure to properly address scale dependence can result in incorrect inferences in multi-scale habitat selection modeling studies.

Objectives

Our goals in this review are to describe the conceptual origins of multi-scale habitat selection modeling, evaluate the current state-of-the-science, and suggest ways forward to improve analysis of scale-dependent habitat selection.

Methods

We reviewed more than 800 papers on habitat selection from 23 major ecological journals published between 2009 and 2014 and recorded a number of characteristics, such as whether they addressed habitat selection at multiple scales, what attributes of scale were evaluated, and what analytical methods were utilized.

Results

Our results show that despite widespread recognition of the importance of multi-scale analyses of habitat relationships, a large majority of published habitat ecology papers do not address multiple spatial or temporal scales. We also found that scale optimization, which is critical to assess scale dependence, is done in less than 5 % of all habitat selection modeling papers and less than 25 % of papers that address “multi-scale” habitat analysis broadly defined.

Conclusions

Our review confirms the existence of a powerful conceptual foundation for multi-scale habitat selection modeling, but that the majority of studies on wildlife habitat are still not adopting multi-scale frameworks. Most importantly, our review points to the need for wider adoption of a formal scale optimization of organism response to environmental variables.
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Sentinel lymph node mapping and biopsy are important parts of oncologic staging in human medicine. Sentinel lymph node mapping enables identification of the first lymph node to receive lymphatic drainage while avoiding unnecessary lymph node dissection. Anal sac adenocarcinoma is the most common malignant neoplasm of the canine perineal area. For dogs with anal sac adenocarcinoma, lympadenectomy and metastasis to the iliosacral lymphocentrum are negative prognostics indicators. The objectives of this prospective, two by two, crossover pilot study were to establish the feasibility of lymphoscintigraphy using Technetium‐99 sulfur colloid of the canine anal sac of healthy dogs, compare two injection techniques, and the time for identification of sentinel lymph nodes using each technique. We hypothesized that both intramural and perimural injections of the canine anal sac would identify similar sentinel lymph node drainage. The sentinel lymph node was identified in all dogs using either technique. Intramural injection of the canine anal sac showed radiopharmaceutical uptake faster than perimural injection technique (P = 0.040). There was concordance between intramual and perimural techniques for the sentinel lymph node identified in 50% of cases. A sacral lymph node was identified as sentinel in three of eight dogs (37.5%). Lymphoscintigraphy of the canine anal sac is safe and feasible in normal dogs; however, the method of injection technique seems to have a significant effect on the sentinel lymph node identified.  相似文献   
140.
Primary abdominal visceral soft tissue sarcomas (STSs) are rare tumours in dogs with little information available on outcomes. The goal of this retrospective, multi‐institutional study was to describe the common tumour types, location and prognostic factors associated with primary abdominal visceral STSs. Medical records were searched for dogs with primary abdominal visceral STSs at six institutions and were retrospectively reviewed. Tumours were graded using the previously described grading scheme for STSs of the skin and subcutis when information in the histopathology report contained adequate details. Forty‐two dogs were included in the study. Five dogs had grade I tumours, 11 had grade II and 15 had grade III tumours. The most common tumour type was leiomyosarcoma (38.1%). The most common tumour locations were the spleen (47.6%) and small intestine (23.8%). The local recurrence rate was low (4.7%). Metastasis was present at the time of surgery in 23.8%, and the overall metastatic rate was 40.4%. Mitotic index of ≥9 was associated with significantly shorter survival time (MST 269 days) compared with a mitotic index of <9 (MST not reached). The MST for grade I STSs was not reached, was 589 days for grade II and 158 days for grade III. Dogs with grade III tumours were more likely to develop metastatic disease. Neither location of the primary tumour nor the histologic subtype was associated with survival time. Histologic grading of abdominal visceral STSs using the previously described scheme is prognostic and should be provided on histopathology reports.  相似文献   
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