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Objective

To determine the effect of fentanyl on the induction dose and minimum infusion rate of alfaxalone required to prevent movement in response to a noxious stimulus (MIRNM) in dogs.

Study design

Experimental crossover design.

Animals

A group of six healthy, adult, intact female mixed-breed dogs, weighing 19.7 ± 1.3 kg.

Methods

Dogs were randomly administered one of three treatments at weekly intervals: premedication with 0.9% saline (treatment A), fentanyl 5 μg kg–1 (treatment ALF) or fentanyl 10 μg kg–1 (treatment AHF), administered intravenously over 5 minutes. Anesthesia was induced 5 minutes later with incremental doses of alfaxalone to achieve intubation and was maintained for 90 minutes in A with alfaxalone (0.12 mg kg–1 minute–1), in ALF with alfaxalone (0.09 mg kg–1 minute–1) and fentanyl (0.1 μg kg–1 minute–1) and in AHF with alfaxalone (0.06 mg kg–1 minute–1) and fentanyl (0.2 μg kg–1 minute–1). The alfaxalone infusion was increased or decreased by 0.006 mg kg–1 minute–1 based on positive or negative response to antebrachium stimulation (50 V, 50 Hz, 10 ms). Data were analyzed using a mixed-model anova and presented as least squares means ± standard error.

Results

Alfaxalone induction doses were 3.50 ± 0.13 (A), 2.17 ± 0.10 (ALF) and 1.67 ± 0.10 mg kg–1 (AHF) and differed among treatments (p < 0.05). Alfaxalone MIRNM was 0.17 ± 0.01 (A), 0.10 ± 0.01 (ALF) and 0.07 ± 0.01 mg kg–1 minute–1 (AHF) and differed among treatments. ALF and AHF decreased the MIRNM by 44 ± 8% and 62 ± 5%, respectively (p < 0.05). Plasma alfaxalone concentrations at MIRNM were 5.82 ± 0.48 (A), 4.40 ± 0.34 (ALF) and 2.28 ± 0.09 μg mL–1 (AHF).

Conclusions and clinical relevance

Fentanyl, at the doses studied, significantly decreased the alfaxalone induction dose and MIRNM.  相似文献   
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Two male intact dwarf rabbits (Oryctolagus cuniculus), 20 and 26 months old, were diagnosed with traumatic long bone fractures of the radius/ulna and tibia, respectively. Transfixation pin splinting, a technique adapted from large animal orthopedics, was used to stabilize the long bone fractures in both rabbits. Bony union with return to normal limb function was achieved in both cases within 6 weeks. The 2 cases were followed for up to 14 months after surgery, and each patient's affected leg returned to normal function. Transfixation pin splints can provide a safe and effective alternative to traditional small animal fracture repairs in domestic rabbits.  相似文献   
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Despite ongoing public health messages about the risks associated with bat contact, the number of potential exposures to Australian bat lyssavirus (ABLV) due to intentional handling by members of the general public in Queensland has remained high. We sought to better understand the reasons for intentional handling among these members of the public who reported their potential exposure to inform future public health messages. We interviewed adults who resided in a defined geographic area in South East Queensland and notified potential exposure to ABLV due to intentional handling of bats by telephone between 1 January 2012 and 31 December 2013. The participation rate was 54%. Adults who reported they had intentionally handled bats in South East Queensland indicated high levels of knowledge and perception of a moderately high risk associated with bats with overall low intentions to handle bats in the future. However, substantial proportions of people would attempt to handle bats again in some circumstances, particularly to protect their children or pets. Fifty‐two percent indicated that they would handle a bat if a child was about to pick up or touch a live bat, and 49% would intervene if a pet was interacting with a bat. Future public health communications should recognize the situations in which even people with highrisk perceptions of bats will attempt to handle them. Public health messages currently focus on avoidance of bats in all circumstances and recommend calling in a trained vaccinated handler, but messaging directed at adults for circumstances where children or pets may be potentially exposed should provide safe immediate management options.  相似文献   
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ABSTRACT A marked-isolate, release-recapture experiment was conducted to assess the relative contributions of seed-transmitted (released isolates) versus all other inocula to foliar and grain populations of Phaeosphaeria nodorum in winter wheat rotated with nonsusceptible crops in New York and Georgia, United States. Seed infected with two distinct groups of marked isolates of P. nodorum containing rare alleles (identified by amplified fragment length polymorphisms [AFLPs]) and balanced for mating type were planted in experimental field plots in two locations in each state. Recapture was done by isolating P. nodorum from leaves showing necrotic lesions at spring tillering and flowering stages, and mature grains from spikes showing glume blotch. Isolates from these samples were genotyped by AFLPs and categorized as released or nonreleased to infer sources of inoculum. Both infected seed and other sources of the pathogen contributed significant primary inocula to populations recovered from leaves and harvested grain. Seed-transmitted genotypes accounted for a total of 57% of all isolates recovered from inoculated plots, with a range of 15 to 90% of the populations of P. nodorum collected over the season in individual, inoculated plots at the four locations. Plants in the noninoculated control plots also became diseased and 95% or more of the isolates recovered from these plots were nonreleased genotypes. Although other potential sources of P. nodorum within and adjacent to experimental plots were not ruled out, nonreleased genotypes likely were derived from immigrant ascospores potentially from sources at a considerable distance from the plots. Our results suggest that, although reduction of seedborne inoculum of P. nodorum may delay foliar epidemics, this strategy by itself is unlikely to result in high levels of control in eastern North America because of the additional contribution from alternative sources of inoculum.  相似文献   
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