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981.
Veterinarians play a unique role in emergency preparedness and response, and federal agencies and academic institutions therefore allocate considerable resources to provide training to enhance their readiness. However, the level of preparedness of veterinarians in many rural regions is yet to be improved. This article reports an assessment of the bioterrorism preparedness, specifically the experience and training needs, of rural veterinarians in North Texas. The study employed a cross-sectional design with a study population that included all veterinarians (N = 352) in the 37 counties within Texas Department of State Health Services Regions 2 and 3. Data on veterinarians practicing or residing in the target region were obtained from the Texas State Board of Veterinary Medical Examiners. The response rate was 35% (n = 121). Results indicate that chemical exposure was the condition most frequently seen and treated, followed by botulism and anthrax. The majority (80%) of respondents indicated that they had not previously participated in training related to bioterrorism preparedness, and many (41%) also indicated a willingness to participate in a state health department-initiated bioterrorism response plan. However, only 18% were confident in their ability to diagnose and treat bioterrorism cases. These results suggest that many North Texas veterinarians practicing in rural regions could benefit from additional training in bioterrorism preparedness and response. An area in particular need of further training is the diagnosis and treatment of Category A agents. Federal, state, and local health agencies are urged to increase training opportunities and to make additional efforts to involve veterinarians in bioterrorism preparedness and response.  相似文献   
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Context

Corridors are usually delineated as areas of minimum cumulative resistance to movement through a resistance surface and characterized by their effective distance (accumulated resistance along the least-cost path). The results of these assessments depend on resistance values, which are typically derived from the inverse of habitat suitability models or from presence data of individuals within their home ranges, rather than from data on dispersal or exploratory movements.

Objective

Evaluate the extent to which corridor delineation and effective distance estimates may vary depending on whether home range locations or dispersal data are used to characterize species habitat selection and landscape resistance to movement.

Methods

We analyzed a large telemetry dataset (GPS collars) for the endangered Iberian lynx. We modeled corridors and effective distances three ways: (1) considering only GPS locations within home ranges, (2) considering only locations in dispersal or exploratory movements outside home ranges, and (3) considering all locations together.

Results

Delineated least-cost corridors followed similar trajectories and sometimes overlapped in the three models. The estimated effective distances were 42 % lower in the dispersal-based model than in the model based solely on home range use.

Conclusions

Models derived exclusively from locations within home ranges may provide lower connectivity estimates than models derived from dispersal locations, affecting estimates of resistance to move between habitat areas, even when the most likely movement routes are similar. Although dispersal data are costly to gather, they potentially provide more realistic assessments of the actual isolation of populations in heterogeneous landscapes.
  相似文献   
985.

Context

Agricultural intensification is a leading cause of landscape homogenization, with negative consequences for biodiversity and ecosystem services. Conserving or promoting heterogeneity requires a detailed understanding of how farm management affects, and is affected by, landscape characteristics.

Objectives

We assessed relationships between farming systems and landscape characteristics, hypothesising that less-intensive systems act as landscape takers, by adapting management to landscape constraints, whereas more intensive systems act as landscape makers, by changing the landscape to suit farming needs.

Methods

We mapped dominant farming systems in a region of southern Portugal: traditional cereal-grazed fallow rotations; specialization on annual crops; and specialization on either cattle or sheep. We estimated landscape metrics in 241 1-km2 buffers representing the farming systems, and analysed variation among and within systems using multivariate statistics and beta diversity metrics.

Results

Landscape composition varied among systems, with dominance by either annual crops (Crop system) or pastures (Sheep), or a mixture between the two (Traditional and Cattle). There was a marked regional gradient of local landscape heterogeneity, but this contributed little to variation among systems. Landscape beta diversity declined from the Sheep to the Crop system, and it was inversely related to agriculture intensity.

Conclusions

Less intensive farming systems appeared compatible with a range of landscape characteristics (landscape takers), and may thus be particularly suited to agri-environmental management. More intensive systems appeared less flexible in terms of landscape characteristics (landscape makers), likely promoting regional homogenization. Farming systems may provide a useful standpoint to address the design of agri-environment schemes.
  相似文献   
986.
Tropical Animal Health and Production - Prolactin (PRL), growth hormone (GH), and insulin-like growth factor-1 (IGF-1) are in hormone-response pathways involved in energy metabolism during...  相似文献   
987.
988.

Objective

To study the effect of alternating the order of midazolam and alfaxalone administration on the incidence of behavioural changes, alfaxalone induction dose and some cardiorespiratory variables in healthy dogs.

Study design

Prospective, randomized, controlled, clinical trial.

Animals

A total of 33 client-owned dogs undergoing elective procedures.

Methods

Following intramuscular acepromazine (0.02 mg kg?1) and morphine (0.4 mg kg?1) premedication, anaesthesia was induced intravenously (IV) with a co-induction of either midazolam (0.25 mg kg?1) prior to alfaxalone (0.5 mg kg?1; group MA), or alfaxalone followed by midazolam at identical doses (group AM). The control group (CA) was administered normal saline IV prior to alfaxalone administration. Additional alfaxalone (0.25 mg kg?1 increments) was administered as required in all groups until orotracheal intubation was possible. Changes in behaviour, quality of induction, ease of intubation and incidence of adverse events at induction were recorded. Heart rate (HR), respiratory rate (fR) and systolic arterial blood pressure (SAP) were measured before treatments (baseline values), 30 minutes after premedication and at 0, 2, 5 and 10 minutes postintubation.

Results

The incidence of excitement was higher in group MA compared with groups CA (p = 0.005) and AM (p = 0.013). The mean induction dose of alfaxalone was lower in group AM compared with group CA (p = 0.003). Quality of induction and ease of intubation were similar among groups. Mean HR values decreased after premedication and increased after alfaxalone administration in all groups. Mean SAP values were similar between groups. The number of animals that required manual ventilation was higher in the MA group.

Conclusions and clinical relevance

Despite a lower occurrence of adverse events at induction in group AM compared with group MA and a reduction of alfaxalone dose requirement in group AM compared with group CA, the use of an alfaxalone–midazolam co-induction does not seem to produce any cardiovascular or respiratory benefits in healthy dogs.  相似文献   
989.
Tropical Animal Health and Production - Subclinical hypocalcemia is a metabolic disorder characterised by a decrease in serum calcium (Ca) levels, with no clinical symptoms. The aim of this study...  相似文献   
990.
The objective of this study was to evaluate the genotype–environment interaction effect on age at first calving in buffaloes. The records were analysed using two approaches: (a) standard animal model and (b) reaction norm model. For the reaction norm analysis, two environmental gradients were formed, using age of first calving or milk yield group contemporary average. The results showed differences in the heritability estimates when using the two approaches. The reaction norm model indicated high heritability in more favourable environments and low magnitude genetic correlations between extreme environments. Based on our findings, we verified the significance of the genotype–environment interaction effect on age at first calving in buffaloes.  相似文献   
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