Detection Of Drugs Research Articles

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.

Some Behavioral Features Required for the Selection of Detection Dogs

Relationships between the detection time of the target objects (drugs) and the individual behavioral characteristics of dogs have been studied. The following parameters of the individual behavior of the dogs were recorded: Sociability, Activity, Play, Reactions to the unexpected appearance of an unfamiliar object, and Noise. It has been noted that the dogs with high rates of sociability and playing and average rates of activity turned out to be the most successful in the searching. It has been found that in different breeds, the time of drug detection depends on their behavioral parameters, has own specifics, and is not gender-related. Various tests for some dog breeds for selection of the most promising detecting individuals have been recommended.

Computed Tomographic Evaluation of the Sacroiliac Joints of Young Working Labrador Retrievers of Various Work Status Groups: Detected Lesions Vary Among the Different Groups and Finite Element Analyses of the Static Pelvis Yields Repeatable Measures of Sacroiliac Ligament Joint Strain.

Musculoskeletal injuries can lead to a working dog being withdrawn from service prior to retirement. During training exercises, young working dogs are often required to perform repetitive tasks, including adoption of an upright posture (or “hupp” task). Non-invasive, quantitative methods would be helpful for supporting research on effects of these repetitive tasks on sacroiliac joints (SIJ). Furthering our understanding of lesions in and biomechanical stresses on the SIJ could provide insight into possible training modifications for minimizing risks of SIJ injury. Aims of this retrospective, secondary analysis, exploratory study were to test hypotheses that (1) mean numbers of SIJ computed tomographic (CT) lesions/dog would differ among work status groups in young working Labrador Retrievers; (2) a methodology for using CT data and finite element analysis (FEA) to quantify SIJ ligament strain in the static canine pelvis would be feasible; and (3) this FEA methodology would yield repeatable measures of SIJ ligament strain. Clinical and CT data for 22 Labrador retriever working dogs, aged 11–48 months, were retrospectively reviewed. Dogs were categorized into three work status groups (Breeder, Detection, Other). A veterinary radiologist who was unaware of dog group status recorded numbers of CT lesions for each SIJ, based on previously published criteria. Mean numbers of SIJ CT lesions/dog were compared among dog work status groups. An a priori FEA model was created from the CT images of one of the dogs using image analysis software packages. Using tissue properties previously published for the human pelvis, various directional loads (n = 8) and forces (48 ligament strain values) were placed on the canine model in five trials. Repeatability was tested using regression analysis. There was a significantly greater mean number of subchondral sclerosis lesions in left SIJ of Breeder vs. Detection dogs, a significantly greater mean number of subchondral cysts in right SIJ for Detection vs. Breeder dogs, and a significantly greater mean number of subchondral cysts in right SIJ of Other vs. Breeder dogs (p < 0.05). Finite element modeling and analysis using CT data was feasible and yielded repeatable results in 47/48 (98%) of tests at each combination of strain, ligament, and side.

Could bio-detection dogs be used to limit the spread of COVID-19 by travellers?

The COVID-19 epidemic has had an unprecedented impact on the tourism sector. Trained disease detection dogs could be used for non-invasive screening at border entry points to reduce the likelihood of re-introduction of SARS-CoV-2 and limit the need for the self-isolation of all passengers.

Factors affecting carcass detection at wind farms using dogs and human searchers

Abstract The use of detection dogs to effectively monitor bird and bat fatalities at wind farms is becoming increasingly popular. All studies to date agree that dogs outperform human searchers at finding bird and bat carcasses around wind turbines; however, it remains unclear how characteristics of the carcass and environmental conditions during the search may influence detection. We investigate the effect of carcass size, vegetation characteristics and weather conditions on the probability of detecting a carcass, for both dogs and humans, using data from the monitoring program of a wind farm in Spain. A generalized linear mixed model reveals a high performance of dogs (~80% detection rate), with no clear influence of any of the variables analysed. Humans, on the contrary, were markedly affected by the size of the carcass and to some extent, by the vegetation structure. Humans performed poorly at detecting small carcasses (~20% detection rate), more so in closed vegetation. Synthesis and applications. Our results provide evidence that dogs perform with high success rates at detecting bird and bat carcasses of different sizes under a wide range of environmental conditions. Humans, by contrast, were very poor at detecting all but the largest carcasses in open areas. We find the use of detection dogs at wind farms to be a robust and cost‐effective alternative to using human searchers, most notably, when the focus is on the monitoring of fatalities of small, rare or inconspicuous species in closed vegetation.

Effectiveness of PennHIP and Orthopedic Foundation for Animals measurements of hip joint quality for breeding selection to reduce hip dysplasia in a population of purpose-bred detection dogs

To examine the effectiveness of applying selective pressure to improve hip joint quality in purpose-bred detection dogs by use of PennHIP distraction index (DI) values along with Orthopedic Foundation for Animals (OFA) hip joint scores and to determine whether age, sex, coat color, breed, and body weight were associated with hip joint quality. 615 purpose-bred detection dogs assessed for hip joint quality. Orthopedic records of 615 purpose-bred detection dogs (569 Labrador Retrievers and 46 Labrador Retriever-German Wirehaired Pointer crossbred dogs) from 2000 through 2017 were analyzed. From 2000 to 2014, hip joint quality scores were determined by OFA evaluation only (429 dogs). Beginning in 2015, both PennHIP and OFA evaluations were used to select male and female breeding stock (179 dogs; 7 dogs were removed from analysis because they did not undergo both evaluations). Selection threshold DI value for sires and dams was ≤ 0.30; all had hip joint scores of excellent or good by OFA standards. Standard ventrodorsal hip joint-extended and stress (compression and distraction) pelvic radiographs were submitted for OFA and PennHIP evaluations. Hip joint quality scores were unchanged by use of OFA measurements only. When both PennHIP and OFA measurements were used for the selection of breeding stock, hip joint quality scores improved significantly. Sex and age were significant predictors of DI values. PennHIP DI values were an effective measurement of hip joint quality for selecting breeding stock, and the addition of DI values to OFA measurements significantly improved hip joint quality in a population of purpose-bred dogs.

Stinkfrucht in Schweinfurt and sniffer dogs on the scent of SARS-CoV-2

On Saturday, June 20, several employees at the post office in the Bavarian town of Schweinfurt started feeling ill. It was just before 8:30 a.m., and a smelly gas was escaping from one of the packa...

Scent dog identification of samples from COVID-19 patients \u2013 a pilot study

BackgroundAs the COVID-19 pandemic continues to spread, early, ideally real-time, identification of SARS-CoV-2 infected individuals is pivotal in interrupting infection chains. Volatile organic compounds produced during respiratory infections can cause specific scent imprints, which can be detected by trained dogs with a high rate of precision.MethodsEight detection dogs were trained for 1 week to detect saliva or tracheobronchial secretions of SARS-CoV-2 infected patients in a randomised, double-blinded and controlled study.ResultsThe dogs were able to discriminate between samples of infected (positive) and non-infected (negative) individuals with average diagnostic sensitivity of 82.63% (95% confidence interval [CI]: 82.02–83.24%) and specificity of 96.35% (95% CI: 96.31–96.39%). During the presentation of 1012 randomised samples, the dogs achieved an overall average detection rate of 94% (±3.4%) with 157 correct indications of positive, 792 correct rejections of negative, 33 incorrect indications of negative or incorrect rejections of 30 positive sample presentations.ConclusionsThese preliminary findings indicate that trained detection dogs can identify respiratory secretion samples from hospitalised and clinically diseased SARS-CoV-2 infected individuals by discriminating between samples from SARS-CoV-2 infected patients and negative controls. This data may form the basis for the reliable screening method of SARS-CoV-2 infected people.

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.

Cadaver Dogs and the Deathly Hallows-A Survey and Literature Review on Selection and Training Procedure.

Simple SummaryDogs are used in many contexts, including the detection of odor sources. A particular application of dogs during searching activities is the location of human remains. In this work, we aimed to gather the common practices of police dog handlers based on a survey made of nine questions, which was sent to police dog handlers around the world (NCountries = 10; NBrigades = 16; NHandlers = 50) and then compared to the information available in the scientific literature. We highlighted a wide diversity of selection and training procedures used by handlers. Studies dedicated to human remains detection dogs are not abundant. However, we found key information that should be applied by handlers during the selection and the training of their human remains detection dogs. First of all, they should include the anatomical traits during the dog selection as behavioral traits alone are not representative of their potential. Finally, even if the training procedures are well performed by handlers, we highlighted a wide diversity of homemade training aids. However, no information was found in the literature regarding the effect of the training aids on the dog performances. For these reasons, handlers should create normalized selection and training procedures while scientists should investigate the behavior of these dogs to provide more information to handlers.Human remains detection dogs (HRDDs) are powerful police assets to locate a corpse. However, the methods used to select and train them are as diverse as the number of countries with such a canine brigade. First, a survey sent to human remains searching brigades (Ncountries = 10; NBrigades = 16; NHandlers = 50; Nquestions = 9), to collect their working habits confirmed the lack of optimized selection and training procedures. Second, a literature review was performed in order to outline the strengths and shortcomings of HRDDs training. A comparison between the scientific knowledge and the common practices used by HRDDs brigade was then conducted focusing on HRDDs selection and training procedures. We highlighted that HRDD handlers select their dogs by focusing on behavioral traits while neglecting anatomical features, which have been shown to be important. Most HRDD handlers reported to use a reward-based training, which is in accordance with training literature for dogs. Training aids should be representative of the odor target to allow a dog to reach optimal performances. The survey highlighted the wide diversity of homemade training aids, and the need to optimize their composition. In the present document, key research topics to improve HRDD works are also provided.

A noninvasive environmental monitoring tool for brominated flame-retardants (BFRs) assisted by conservation detection dogs

Fecal matter is a useful noninvasive/nondestructive media for evaluating contaminants in wildlife, as residues therein have been observed to correlate with body burdens. Conservation detection dog-handler teams can be used to optimize the acquisition of fecal samples. To build on previous work, sentinel-species’ (i.e. mink (Mustela vison) and otter (Lontra canadensis)) fecal matter was opportunistically located by a detection dog team along the tri-river system of Missoula, Montana, USA. Sediments were also collected. Samples were used to develop an analytical method from fecal matter to determine habitat exposure to the brominated flame-retardants (BFRs): polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDD), 2-ethylhexyl 2, 3, 4, 5-tetrabromobenzoate (EH-TBB), di (2-ethylhexyl)-2, 3, 4, 5-tetrabromophthalate (BEH-TEBP) and decabromodiphenyl ethane (DBDPE). Sediments contained PBDEs (BDE-99 and BDE-209) and EH-TBB at detection rates of 67%, 33% and 67%, respectively. BDE-99, -209 and EH-TBB were also detected in mink and otter feces, at rates of 81%, 25% and 81%, respectively; plus BEH-TEBP at 13%. BFR levels correlated positively with human population density except along the lower Bitterroot River, where BDE-209 sediment and feces levels exceeded other sites by several orders of magnitude. Fecal matter body burden estimates indicated marginal PBDE exposure. However, exposure to their replacements, EH-TBB and BEH-TEBP, were at levels that may adversely affect healthy Mustelidae populations. Proof-of-concept was achieved; validation results were within established standards for the development of analytical methods. The established application of conservation dog-handler teams to facilitate the collection of fecal matter for BFR analysis represents a valuable, but currently underutilized environmental monitoring tool.

A Novel Multiplex-PCR Assay to Detect Three Non-Halal Meats Contained in Meatball using Mitochondrial 12S rRNA Gene.

The objective of this study was to detect three non-halal meat products consisted of dog, pork, and rat species in meatball using novel multiplex-PCR with 12S rRNA gene as target sites. A total of 33 self-made meatballs were used, and they were grouped into eleven types of meatball based on meat species origin contained in the meatballs. Each type consisted of three meatballs. Extraction of genomic DNA from the meatballs was used as a DNA template for simplex-, duplex-, and multiplex-PCR processes. The result of simplex-PCR, duplex-PCR, and multiplex-PCR showed that the 12S rRNA primer gene successfully amplified DNA for each species bovine, dog, pig, and rat, which are respectively indicated by 155, 244, 357, and 491 bp of DNA bands. In addition, multiplex-PCR with 12S rRNA gene primers can be uniquely and accurately used for detection bovine, dog, pig, and rat species on beef meatball in one reaction.

Non-invasive cancer detection using volatile biomarkers: Is urine superior to breath?

In recent years numerous reports have highlighted the options of chemical breath analysis with regard to non-invasive cancer detection. Certain volatile organic compounds (VOC) supposedly present in higher amounts or in characteristic patterns have been suggested as potential biomarkers. However, so far no clinical application based on a specific set of compounds appears to exist. Numerous reports on the capability of sniffer dogs and sensor arrays or electronic noses to distinguish breath of cancer patients and healthy controls supports the concept of genuine cancer-related volatile profiles. However, the actual compounds responsible for the scent are completely unknown and there is no correlation with the potential biomarkers suggested on basis of chemical trace analysis.It is outlined that specific features connected with the VOC analysis in breath – namely small concentrations of volatiles, interfering background concentrations, considerable sampling effort and sample instability, impracticability regarding routine application - stand in the way of substantial progress. The underlying chemical-analytical challenge can only be met considering the severe susceptibility of VOC determination to these adverse conditions.Therefore, the attention is drawn to the needs for appropriate quality assurance/quality control as the most important feature for the reliable quantification of volatiles present in trace concentration. Consequently, the advantages of urine as an alternative matrix for volatile biomarker search in the context of diagnosing lung and other cancers are outlined with specific focus on quality assurance and practicability in clinical chemistry. The headspace over urine samples as the VOC source allows adapting gas chromatographical procedures well-established in water analysis. Foremost, the selection of urine over breath as non-invasive matrix should provide considerably more resilience to adverse effects during sampling and analysis. The most important advantage of urine over breath is seen in the option to partition, dispense, mix, spike, store, and thus to dispatch taylor-made urine samples on demand for quality control measures. Although it is still open at this point if cancer diagnosis supported by non-invasively sampled VOC profiles will ultimately reach clinical application the advantages of urine over breath should significantly facilitate urgently required steps beyond the current proof-of-concept stage and towards standardisation.

Comparing pet and detection dogs (Canis familiaris) on two aspects of social cognition.

Interspecific communication between dogs and humans enables dogs to occupy significant roles in human society, both in companion and working roles. Dogs excel at using human communicative signals in problem-solving tasks, and solicit human contact when unable to solve a problem. Dogs' sociocognitive behavior likely results from a selection for attention to humans during domestication, but is highly susceptible to environmental factors. Training for particular tasks appears to enhance dog-human communication, but effects may depend on the nature of the relationship determined by their role. Our aim was to examine two types of social cognition (responsiveness to human gestures, and human-directed communicative behavior in an unsolvable task) in pet dogs (n = 29) and detection dogs (n = 35). The groups did not differ in their ability to follow human signals, but pets were less responsive to signals given by a stranger than by their owner. Pets also exhibited more human-directed gazing in the unsolvable task, showing a bias for gazing at their owner compared with the stranger, whereas detection dogs showed greater persistence in attempting to solve the task compared with pets. Thus, different aspects of dogs' sociocognitive behavior may differentially vary as a function of selection or training for particular roles.

Incorporating the sampling effectiveness of detection dogs in the faecal standing crop method

Evaluating the population status of elusive and rare species is a challenge for wildlife managers and conservationists. A promising method that has been used is faecal pellet counting applied to the faecal standing crop (FSC) method. The FSC method estimates population density based on faecal pellets counted in a given area by using parameters such as defecation rate and faecal persistence, which vary according to the environment. The search for faeces has become more effective with the help of scat detection dogs, which have a better detection rate compared to humans. Therefore, we aimed to incorporate the sampling effectiveness of scat detection dogs as parameters in FSC methods. For this purpose, two experiments were conducted to evaluate the detectability of Mazama faeces related to their distance from a search transect and their age (time since deposition). Our results show that incorporating scat detection dog parameters can result in density estimates three times higher than those reached without incorporating the detection dog parameters in FSC methods.

Effect of Handler Knowledge of the Detection Task on Canine Search Behavior and Performance.

Detection dogs are commonly trained and tested under conditions in which the handler or the evaluator knows the true presence or absence of a target odor. Previous research has demonstrated that when handlers are deceived and led to believe that a target odor is present, more false alerts occur. However, many detection teams operate under unknown conditions, and it remains unclear how handler knowledge (or lack thereof) of odor presence/absence influences the dog's behavior. The aim of this study was to evaluate if knowing the number of hides placed influenced detection dog performance in an applied search environment. Professional (n = 20) and sport (n = 39) detection handler-dog teams were asked to search three separate areas (area 1 had one hide, area 2 had one hide, area 3 was blank). Handlers in the Unknown Group were not told any information on the number of hides whereas the Known Group were told there was a total of two hides in the three areas. The sport Unknown Group spent a longer duration (69.04 s) searching in area 3 compared to the sport Known Group (p = 0.004). Further, sport dogs in the Unknown group looked back to the handler more frequently. When a miss did occur, dogs of both sport and professional handlers showed an increase interest in the location of the target odor compared to a comparison location. Critically, however, there was no difference in false alerts between the Known Group and Unknown Group for sport or professional handlers. In a second experiment, fourteen professional, and thirty-nine sport teams from Experiment 1 conducted an additional search double-blind and an additional search single-blind. Both sport and professional-handler dog teams had statistically similar accuracy rate under single and double blind conditions. Overall, when handlers knew the number of hides, it led to significant changes in search behavior of the detection team but did not influence the overall false alert rates.

A Critical Needs Assessment for Research in Companion Animals and Livestock Following the Pandemic of COVID-19 in Humans.

Problem: The emergence of novel coronavirus (SARS-CoV-2) in Wuhan, China, in November 2019 and a growing body of information compel inquiry regarding the transmissibility of infection between humans and certain animal species. Although there are a number of issues to be considered, the following points are most urgent: The potential for domesticated (companion) animals to serve as a reservoir of infection contributing to continued human-to-human disease, infectivity, and community spread. The ramifications to food security, economy, and trade issues should coronavirus establish itself within livestock and poultry. The disruption to national security if SARS-CoV-2 and its fairly well-established effects on smell (hyposmia/anosmia) to critical military service animals including explosive detector dog, narcotics detector dog, specialized search dog, combat tracker dog, mine detection dog, tactical explosive detector dog, improvised explosive device detector dog, patrol explosive detector dog, and patrol narcotics detector dog, as well as multipurpose canines used by special operations such as used by the U.S. customs and border protection agency (e.g., Beagle Brigade). This article presents in chronological order data that both individually (as received independently from multiple countries) and collectively urge studies that elucidate the following questions. 1.What animal species can be infected with SARS-CoV-2, the likely sources of infection, the period of infectivity, and transmissibility between these animals and to other animal species and humans? 2.What are the best diagnostic tests currently available for companion animals and livestock? 3.What expressions of illness in companion and other animal species can serve as disease markers? Although it is recognized that robust funding and methodology need to be identified to apply the best scientific investigation into these issues, there may be easily identifiable opportunities to capture information that can guide decision and study. First, it may be possible to quickly initiate a data collection strategy using in-place animal gatekeepers, such as zookeepers, veterinarians, kennel owners, feed lots, and military animal handlers. If provided a simple surveillance form, their detection of symptoms (lethargy, hyposmia, anosmia, and others) might be quickly reported to a central data collection site if one were created. Second, although current human COVID-19 disease is aligning around areas of population density and cluster events, it might be possible to overlay animal species density or veterinary reports that could signal some disease association in animals with COVID-19 patients. Unfortunately, although companion animals and zoo species have repeatedly served as sentinels for emerging infectious diseases, they do not currently fall under the jurisdiction of any federal agency and are not under surveillance.

Chemiresistive Vapour Sensors Based on a Percolation Network of Conductive Polymers

Introduction: Vapour sensing plays an important role in various safety, security, and healthcare applications. However, it is perhaps surprising that despite modern technologies sniffer dogs are still considered the gold standard in vapour sensing. Achieving high sensitivities often remains challenging. Furthermore, existing technological solutions often require relatively large pieces of equipment, or pre-concentration steps [1].Conductive polymer (CP) based chemiresistive vapour sensors offer a promising solution because of the large range of materials available and their relatively cheap and easy processing methods. Furthermore, their small scale makes it possible to use them in small scale devices. CP based sensors described in literature often use a CP thin film as the sensing layer. Here we demonstrate a significantly improved sensitivity by using a percolation network of CPs instead of a CP thin film. Concept: Electrical percolation describes the likelihood of a current running from an electrode on one side of a network to an electrode on the other side. If there are no electrical connections between the electrodes the conductance is zero. When enough connections are added to the network to form a conductive pathway between the electrodes the conductance increases sharply. When more connections are added to the network the conductance keeps increasing and eventually reaches a plateau. Traditional chemiresistive vapour sensors, consisting of a CP thin film, are operated in this flat part of the percolation curve. We’ve shown that by creating sensors in the steep part of the curve, close to the percolation threshold, a significantly higher sensitivity can be achieved. Experimental: Our sensors consist of a polypyrrole (PPy) network between interdigitated Pt electrodes on a glass substrate. Au nano-islands were used as nodes in the PPy network. Sensors with different polymer coverages, corresponding to different points along the percolation curve, were exposed to various concentrations of ammonia. Results and conclusion: Sensors with polymer coverages corresponding to the steep part of the percolation curve give a significantly higher sensitivity than those in the thin film regime. One would perhaps also expect that the closer to the percolation threshold the better the sensor, however in practice this doesn’t hold true. Moving closer to the percolation threshold from this optimum does result in a higher absolute sensor response, however due to an increase in relative noise the sensitivity decreases when a sensor is too close to the percolation threshold. At this optimum, in the steep part of the percolation curve, we have achieved sensitivities as low as 9 ±2 ppb. Outlook: Further avenues of research that we are currently exploring include increasing the range of sensing materials and analyte vapours, as well as using this sensor technology for specific applications such as the detection of improvised explosives. We are also using percolation networks to improve the sensitivity of sensors on flexible substrates, and for the inclusion of this technology into wearable devices. Finally, we have developed an integrated device that not only allows us to take this technology out of the lab and test it in real-life scenarios, but also allows us to use multiple sensors at the same time in an electronic nose type setup. This allows us to increase our selectivity in addition to the increased sensitivity achieved by using percolation networks of CPs instead of thin films.[1] Lefferts, M. J. & Castell, M. R. Vapour sensing of explosive materials, Analytical Methods 7, 9005-9017 (2015); DOI: 10.1039/C5AY02262B

The development of problem-solving abilities in a population of candidate detection dogs (Canis familiaris).

Both ontogenetic and phylogenetic factors have shaped dogs' cognitive capabilities, resulting in a heightened social sensitivity at the apparent cost of non-social problem-solving abilities. Research has suggested that training history and life experience can influence problem-solving abilities in dogs. However, the ontogenetic development of problem-solving abilities in dogs has been less explored. We tested a population of candidate detection dogs of various ages across the first year of development on four well-established problem-solving tasks targeting different cognitive domains (i.e., cylinder, A-not-B barrier, delayed search, and spatial transposition tasks). We examined developmental effects by comparing cognitive task performance across three age groups. Age-related improvements for all four cognitive measures indicate developmental increases in processes related to inhibitory control, attention, and spatial cognition between 3 and 12months of age. Additionally, we found some relationships between cognitive measures and detection dog performance measures, though effects were not as robust. We discuss the results in the context of canine cognitive development and corresponding effects of phylogeny and ontogeny, as well as potential applications to working dog training and selection.

Body Temperature Responses During Phases of Work in Human Remains Detection Dogs Undergoing a Simulated Deployment.

Simple SummaryWorking dogs are frequently transported via crates in vehicles to various deployment scenarios. Body temperature increase associated with exercise is common but has not been assessed throughout the entire work cycle for dogs during a deployment scenario. We measured continuous temperature changes for dogs throughout an entire day of search operations including each stage of the work cycle, namely waiting-to-work, active work, and post-work recovery. We found that dogs did not increase in temperature while waiting-to-work but temperature did increase during the period of active work. Additionally, when dogs were returned to vehicles for crate and rest during the post-work recovery period, body temperatures continued to increase. We suggest that post-work recovery in the vehicle should be further investigated to better manage dogs through continuing search operations.Body temperature responses were recorded during phases of work (waiting-to-work in close proximity to search site, active work in a search site, and post-work recovery crated in vehicle) in human remains detection dogs during search training. State or federally certified human remains detection dogs (n = 8) completed eight iterations of searching across multiple novel search environments to detect numerous scent sources including partial and complete, buried, hidden, or fully visible human remains. Internal temperature (Tgi) of the body was measured continuously using an ingestible thermistor in the gastrointestinal tract. Mean total phase times were: waiting-to-work: 9.17 min (±2.27); active work: 8:58 min (±2:49); and post-work recovery: 24:04 min (±10.59). Tgi was impacted by phase of work (p < 0.001) with a small increase during active work, with mean peak temperature 39.4 °C (±0.34 °C) during that period. Tgi continued to increase for a mean of 6:37 (±6:04) min into the post-work recovery phase in the handler’s vehicle with a mean peak Tgi of 39.66 °C (±0.41 °C). No significant increase in temperature was measured during the waiting-to-work phase, suggesting behaviors typical of anticipation of work did not appear to contribute to overall body temperature increase during the waiting-to-work recovery cycle. Continued increase of gastrointestinal body temperature several minutes after cessation of exercise indicates that risk of heat injury does not immediately stop when the dog stops exercising, although none of the dogs in this study reached clinically concerning body temperatures or displayed any behavioral signs suggestive of pending heat injury. More work is needed to better understand the impact of vehicle crating on post-work recovery temperatures in dogs.