A Novel Method for Training the Interdiction of Restricted and Hazardous Biological Materials by Detection Dogs.

The interdiction of restricted and hazardous biological agents presents challenges for any detection method due to the inherent complexity of sample type and accessibility. Detection capabilities for this category of agents are limited and restricted in their mobility, adaptability and efficiency. The potential for identifying biological agents through a volatile organic compound (VOC) signature presents an opportunity to use detection dogs in a real-time mobile capacity for surveillance and screening strategies. However, the safe handling and access to the materials needed for training detection dogs on restricted or hazardous biological agents prevents its broader application in this field. This study evaluated the use of a polymer-based training aid in a viral detection model using bovine viral diarrhea virus mimicking biosafety level 3+ agent conditions. After the biological agent-based odor was absorbed into the polymer, the aid was rendered safe for handling through a rigorous sterilization process. The viral culture-based training aid was then used to train a cohort of detection dogs (n = 6) to discriminate agent-based target odor in culture from relevant distractor odors including non-target biological agent-based odors. Following culture-based training, dogs were tested for generalization to aids with infected animal sample-based odors across five sample types (fecal, blood, nasal, saliva, and urine). Within the context of the polymer-based training aid system, dogs were successfully trained to detect and discriminate a representative biological viral agent-based odor from distractor odors with a 97.22% (±2.78) sensitivity and 97.11% (±1.94) specificity. Generalization from the agent-based odor to sample-based odors ranged from 65.40% (±8.98) to 91.90 % (±6.15) sensitivity and 88.61% (±1.46) to 96.00% (±0.89) specificity across the sample types. The restrictive nature for mimicking the access and handling of a BSL 3+ agent presented challenges that required a strict study design uncommon to standard detection dog training and odor presentation. This study demonstrates the need to further evaluate the utility and challenges of training detection dogs to alert to biological samples using safe and manageable training aids.

Selecting Dogs for Explosives Detection: Behavioral Characteristics.

Detection dogs are widely considered the most effective and adaptive method for explosives detection. Increases in emerging sophisticated threats are accelerating the demand for highly capable explosives detection, causing a strain on available supplies of quality canines worldwide. These strains are further compounded by rigorous behavioral standards required to meet mission-specific capabilities, leading to high rates of dogs disqualified from training or deployment. Ample research has explored the behavioral characteristics important for assistance, guide, and other traditional working roles, while those corresponding to more specialized tasks such as detection of explosives are not as well-understood. In this review we aim to identify the behavioral characteristics important for operational tasks of explosives detection dogs, contrasting with that of other working roles and highlighting key differences between explosives and other types of detection dogs. Further, we review the available research on methods for assessing and selecting candidate detection dogs and make recommendations for future directions and applications to the industry. Improvements and standardization in assessment technology allowing for the identification and enhancement of behavioral characteristics will be key to advancing canine detection technology in general.

Methodological Considerations in Canine Olfactory Detection Research.

Dogs are increasingly used in a wide range of detection tasks including explosives, narcotics, medical, and wildlife detection. Research on detection dog performance is important to understand olfactory capabilities, behavioral characteristics, improve training, expand deployment practices, and advance applied canine technologies. As such, it is important to understand the influence of specific variables on the quantification of detection dog performance such as test design, experimental controls, odor characteristics, and statistical analysis. Methods for testing canine scent detection vary influencing the outcome metrics of performance and the validity of results. Operators, management teams, policy makers, and law enforcement rely on scientific data to make decisions, design policies, and advance canine technologies. A lack of scientific information and standardized protocols in the detector dog industry adds difficulty and inaccuracies when making informed decisions about capability, vulnerability, and risk analysis. Therefore, the aim of this review is to highlight important methodological issues and expand on considerations for conducting scientifically valid detection dog research.

Investigation of the Behavioral Characteristics of Dogs Purpose-Bred and Prepared to Perform Vapor Wake® Detection of Person-Borne Explosives.

Specialized detector dogs are increasingly being utilized for the detection of modern threats. The Vapor Wake® (VW) dog was developed to create a dog phenotype ideally suited for detecting hand-carried and body-worn explosives. VW dogs (VWDs) are trained to sample and alert to target odors in the aerodynamic wakes of moving persons, which entrains vapor and small particles from the person. The behavioral characteristics necessary for dogs to be successfully trained and employed for the application of VW are a distinct subset of the desired general characteristics of dogs used for detection tasks due to the dynamic nature of moving targets. The purpose of this study was to examine the behavioral characteristics of candidate detector dogs to determine the particular qualities that set apart VW-capable dogs from others. We assessed 146 candidate detector dogs from a VW breeding and training program. Dogs received identical puppy development and foundational odor training and underwent performance evaluations at 3, 6, 10, and 12 months old, after which they were sold for service. Dogs were categorized based on their final outcome of the training program, independently determined by private vendors, corresponding to three groups: dogs successfully sold for VW, dogs sold for standard explosives detection, and dogs that failed to be placed in any type of detector dog service (Washouts). Comparisons of behavioral evaluations between the groups were made across domains pertaining to search-related behaviors (Performance), reactions to novel stimuli (Environmental), and overall ease of learning new tasks (Trainability). Comparisons were also made at each evaluation to determine any early emergence of differences. VWDs scored significantly higher on Performance characteristics compared to standard explosives detection dogs (EDDs) and Washouts. However, Environmental characteristics did not differentiate VWDs from EDDs, though scores on these measures were significantly lower in the Washouts. Furthermore, differences between groups emerged as early as 3 and 6 months for select measures. We describe the behavioral characteristics targeted for selection in developing the VW phenotype and discuss the relative merit and degree of expression of those characteristics in the success of dogs bred and trained for the VW application.

Canine Detection of the Volatilome: A Review of Implications for Pathogen and Disease Detection.

The volatilome is the entire set of volatile organic compounds (VOC) produced by an organism. The accumulation of VOC inside and outside of the body reflects the unique metabolic state of an organism. Scientists are developing technologies to non-invasively detect VOC for the purposes of medical diagnosis, therapeutic monitoring, disease outbreak containment, and disease prevention. Detection dogs are proven to be a valuable real-time mobile detection technology for the detection of VOC related to explosives, narcotics, humans, and many other targets of interests. Little is known about what dogs are detecting when searching for biological targets. It is important to understand where biological VOC originates and how dogs might be able to detect biological targets. This review paper discusses the recent scientific literature involving VOC analysis and postulates potential biological targets for canine detection. Dogs have shown their ability to detect pathogen and disease-specific VOC. Future research will determine if dogs can be employed operationally in hospitals, on borders, in underserved areas, on farms, and in other operational environments to give real-time feedback on the presence of a biological target.

The effects of exercise and diet on olfactory capability in detection dogs.

A previous work suggests that dietary fat may influence canine olfaction. The present study evaluated whether olfactory performance could be influenced by forms of dietary fat and exercise. Seventeen certified detection dogs were fed three different diets (high fat, low fat or high polyunsaturated fat) for 12 weeks. After 12 weeks, olfactory testing was performed using a scent wheel in an olfaction laboratory using three explosive materials. The dogs completed eight to twelve scent trials before and after a 30 min treadmill exercise on five consecutive days. A mixed-effect logistic regression model was used to examine how diet, pre- or post-exercise, trial number, odourant, mass of target and target position influenced the probability of dogs alerting on the target odour. There were no significant changes in the dog's ability to find a target odour at threshold amounts. Dogs were 1·42 (1·08, 1·87; 95 % CI) times as likely to find a target on the high polyunsaturated fat diet relative to the high-fat diet (P = 0·009). The low-fat diet was not significantly different from either the high-fat diet or the high polyunsaturated fat diet (P = 0·12). Dogs were 1·49 (1·26, 1·76; 95 % CI) times as likely to find a target prior to exercise relative to after exercise (P < 0·001). Dogs on the high PUFA diet utilising maize oil showed mild improvement in olfaction. The exact reasons are unknown; however, the higher relative amount of linoleic acid in the diet may play a role in olfactory sensation which warrants further examination of optimal diets for detection dogs.

Evaluation of exercise-induced changes in concentrations of C-reactive protein and serum biochemical values in sled dogs completing a long-distance endurance race.

OBJECTIVE: To determine whether long-distance endurance exercise in sled dogs causes increases in serum concentrations of C-reactive protein (CRP) and whether such increases are correlated with other markers of the exercise-induced acute-phase response. ANIMALS: 25 sled dogs. PROCEDURES: Serum was obtained from 25 sled dogs approximately 48 hours before and immediately after completing a race of 557 km. Serum was analyzed to determine concentrations of CRP and interleukin (IL)-6, and serum biochemical analysis (and iron homeostasis analysis) also was performed. RESULTS: CRP concentrations increased significantly from a mean±SD concentration of 22.4±16.3 microg/mL before racing to a mean of 263.3±103.8 microg/mL immediately after racing Serum IL-6 concentrations were unchanged; however, there was a modest but significant correlation (r=0.50) between the increase in CRP concentration and an overall decrease in serum albumin concentration, which suggested an inverse relationship between hepatic synthesis of the 2 proteins. Differences in CRP concentrations among teams of dogs revealed that concentrations before racing may be influenced by previous episodes of exercise. Serum iron concentration had only a mild decrease, which may have been attributable to iron-rich diets consumed by the dogs. CONCLUSIONS AND CLINICAL RELEVANCE: CRP concentrations may serve as a potential marker for exercise-induced inflammation. The exact amount of exercise required to induce such a response is unknown, but dogs apparently have a more robust acute-phase response than do humans. Clinical evaluation of CRP concentrations must account for physical activity when those concentrations are used as a potential marker for systemic inflammation.

Hematologic, serum biochemical, and cortisol changes associated with anticipation of exercise and short duration high-intensity exercise in sled dogs.

BACKGROUND: Many studies have demonstrated changes in clinicopathologic variables in response to exercise in athletic dogs. These changes have been attributed to the duration and intensity of exercise. However, inconsistencies in the timing of collection of resting blood samples can be a confounding variable when interpreting results. OBJECTIVES: The objectives of this study were to determine whether hematologic and biochemical data in sled dogs are influenced by (1) anticipation of an exercise event or (2) short-duration high-intensity exercise. METHODS: Blood samples were collected into EDTA tubes and tubes without anticoagulant from sled dogs at rest, immediately before a 3-mile run (preexercise), and immediately after the run (postexercise). A CBC, biochemical profile (including electrolytes, glucose, proteins, creatinine, urea, enzymes, cholesterol, and total bilirubin), and serum cortisol concentration were measured using standard methods on automated analyzers. RESULTS: Significant increases in sodium, chloride, albumin, calcium, and cortisol concentration were observed in preexercise samples when compared with resting samples. Hyperglycemia and a further rise in serum cortisol concentration occurred immediately postexercise. CONCLUSIONS: The results of this study indicate that anticipation of exercise affects several biochemical analytes, emphasizing the importance of appropriate timing of baseline blood samples. The pronounced hyperglycemia immediately after short-duration exercise may be a breed- or exercise-dependent phenomenon.