A canine model to evaluate the effect of exercise intensity and duration on olfactory detection limits: the running nose.

Detection canines serve critical roles to support the military, homeland security and border protection. Some explosive detection tasks are physically demanding for dogs, and prior research suggests this can lead to a reduction in olfactory detection sensitivity. To further evaluate the effect of exercise intensity on olfactory sensitivity, we developed a novel olfactory paradigm that allowed us to measure olfactory detection thresholds while dogs exercised on a treadmill at two different exercise intensities. Dogs (n = 3) showed a decrement in olfactory detection for 1-bromooctane at 10-3 (v/v) dilutions and lower under greater exercise intensity. Dogs' hit rate for the lowest concentration dropped from 0.87 ± 0.04 when walking at low intensity to below 0.45 ± 0.06 when trotting at moderate intensity. This decline had an interaction with the duration of the session in moderate intensity exercise, whereby dogs performed near 100% detection in the first 10 min of the 8 km/h session, but showed 0% detection after 20 min. Hit rates for high odor concentrations (10-2) were relatively stable at both low (1 ± 0.00) and moderate (0.91 ± 0.04) exercise intensities. The paradigm and apparatus developed here may be useful to help further understand causes of operationally relevant olfactory detection threshold decline in dogs.

Biocidal effects of a wipe-down procedure using common veterinary cleansers on microbial burden within working canine exterior coats.

Introduction: Recent work demonstrating reduction of aerosolized contamination via a wipe-down procedure using common veterinary antiseptics offers promise regarding health concerns associated with cross-contamination from working canines to humans. While mechanical reduction can be achieved via a wipe-down procedure, the biocidal impact on flora within the exterior coat is unknown. Methodology: This study assessed the biocidal impact of antiseptics on the exterior bacterial community of the canine. Lint-free towels were saturated with 2% chlorhexidine gluconate scrub, or 7.5% povidone-iodine scrub diluted at a 1:4 ratio. Treatments were rotated across the dorsal aspect of kennel housed Foxhounds (n = 30). Sterile swabs were collected in triplicate prior to, and following wipe down, stored in Amies solution at 4°C, plated onto nutrient agar and reduction in colony forming units (CFU) was measured across both treatments. Statistical analysis utilizing PROC GLM examined effects of treatment (p ≤ 0.05). Molecular analysis of the 16S rRNA gene was completed for 3 hounds. Results: Reduction in CFU was measured (p < 0.001) for both antiseptics. Qualitative molecular data indicated that both antiseptics had a biocidal effect on the dominant microbial community on the exterior coat with gram-positive, spore-forming taxa predominating post-treatment. Conclusion: Effective wipe-down strategies using common veterinary cleansers should be further investigated and incorporated to safeguard working canine health and prevent cross-contamination of human personnel.

An assessment of working canine contamination from standing liquid hazards during a simulated disaster search scenario.

Working canines have the potential to be exposed to hazardous materials during search and rescue deployments. Unfortunately, little data are available regarding likely areas of contamination on working canines or effective techniques for substance removal. We describe recent work using an oil-based UV fluorescent marker pooled to mimic standing liquid hazards in a simulated disaster scene to characterize anatomical locations likely to be contaminated. This study utilized three simulated "contaminated" environments situated across a disaster training complex. Federal Emergency Management Agency (FEMA) working canines (n = 11) searched the simulated disaster scene and traversed each contaminated environment. Following the search, all canines were kenneled for 30 minutes and then photographed to capture anatomic locations of exposure. The canines were then taken immediately to the decontamination station where handlers' attempts at canine decontamination were recorded. Anatomical locations were coded as ventral or dorsal, and then further subdivided to the neck, chest, lower legs, and paws for ventral exposures; and back, head, face, and hips for dorsal exposures. Contamination occurred consistently on the paws and lower legs with overall ventral exposure occurring in 39 of 44 (89%) observations. Contamination of the back and head was infrequent, with overall dorsal exposure occurring in 11 of 44 (25%) observations. Despite handler awareness of the exact anatomical locations of exposure with a greater frequency of exposure involving ventral (78%) versus dorsal (22%) regions of the canine (P < 0.0001), time spent decontaminating the two regions did not differ (P = 0.881). These data indicate a need for additional research to identify effective decontamination techniques. Furthermore, the results suggest that additional training may be needed to educate handlers and veterinary personnel regarding anatomic locations on working canines likely to be contaminated during disaster operations in environments where standing liquid hazards are present.

Removal of Aerosolized Contaminants from Working Canines via a Field Wipe-Down Procedure.

Evidence-based canine decontamination protocols are underrepresented in the veterinary literature. Aerosolized microbiological and chemical contaminants can pose a risk in deployment environments highlighting the need for improved canine field decontamination strategies. Prior work has established the efficacy of traditional, water-intensive methods on contaminant removal from the coat of the working canine; however, it is not known if similar reductions can be achieved with simple field expedient methods when resources are limited. The objective of this study was to measure the reduction of aerosolized contamination via a practical "wipe-down" procedure performed on working canine coats contaminated with a fluorescent, non-toxic, water-based aerosol. Disposable, lint-free towels were saturated with one of three treatments: water, 2% chlorhexidine gluconate scrub (CHX), or 7.5% povidone-iodine scrub (PVD). Both CHX and PVD were diluted at a 1:4 ratio. Treatments were randomly assigned to one of three quadrants established across the shoulders and back of commonly utilized working dog breeds (Labrador retrievers, n = 16; German shepherds, n = 16). The fourth quadrant remained unwiped, thus serving as a control. Reduction in fluorescent marker contamination was measured and compared across all quadrants. PVD demonstrated greater marker reduction compared to CHX or water in both breeds (p < 0.0001). Reduction was similar between CHX or water in Labradors (p = 0.86) and shepherds (p = 0.06). Effective wipe-down strategies using common veterinary cleansers should be further investigated and incorporated into decontamination practices to safeguard working canine health and prevent cross-contamination of human personnel working with these animals.

An Assessment of Decontamination Strategies for Materials Commonly Used in Canine Equipment.

Working canines are frequently exposed to hazardous environments with a high potential for contamination. Environmental contamination may occur in many ways. Contamination may be chemical, biological, radiological, or nuclear. Examples may include a pipeline rupture following an earthquake, microbiological contamination of floodwaters, or exposure to toxic industrial chemical such as hydrogen chloride, ammonia, or toluene. Evidence to support effective methods for decontamination of equipment commonly used by working canines is lacking. Recent work has identified decontamination protocols for working canines, but little data are available to guide the decontamination of equipment used during tactical operations. The objective of our work was to investigate the effects of cleanser, cleaning method, and material type on contaminant reduction for tactical canine equipment materials using an oil-based contaminant as a surrogate for toxic industrial chemical exposure. A contaminant was applied, and effectiveness was represented as either success (= 50% contaminant reduction) or failure (< 50% contaminant reduction). A two-phase study was used to investigate cleanser, method of cleaning, and material types for effective contaminant reduction. In phase 1, Simple Green® cleanser had a higher frequency (P = .0075) of failure, but method and material did not affect contamination reduction (P > .05). In phase 2, Dawn® (P = .0004) and Johnson's® (P = .0414) successfully reduced contamination. High-pressure cleaning (HPC) resulted in successful decontamination (P < .0001). These novel data demonstrate potential techniques for reduction of contaminants on tactical canine equipment.