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Cropper E, Riley P, Simon AG. Towards maintaining canine training aid integrity: Effects of environmental factors and operational use on the triacetone triperoxide polymer odor capture-and-release system. J Forensic Sci 2024; 69:888-904. [PMID: 38528830 DOI: 10.1111/1556-4029.15507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 02/15/2024] [Accepted: 03/06/2024] [Indexed: 03/27/2024]
Abstract
There are many factors that may affect the longevity of or guide the use of canine training aids. Literature to date has mainly focused on identifying the headspace volatiles associated with training aids or odors and only minimal research exists into how different variables may alter those volatiles. The current study examines several factors affecting canine training aids: humidity, air flow, transportation, and operational deployment, using the triacetone triperoxide polymer odor capture-and-release canine training aid (TATP POCR) as the target. The TATP POCR is an absorption-based canine training aid developed to be used to safely train canines to detect the odor of the explosive TATP in operational settings. Comparisons of the TATP POCR to neat TATP are made throughout the manuscript. First, humidity increased the background components of the POCR matrix, as well as the amount of TATP recovered was above the POCR. Humidity thus affected the amount of TATP detected but did not prevent detection. Second, air flow lessened the lifetime of the TATP POCR. Third, the practice of using primary and secondary containment successfully prevented contamination, cross-contamination, and significant target loss, thereby maintaining kit integrity. Finally, the absorption of background odors from training environments was not observed. TATP headspace concentrations between a Deployed and Control POCR kit were not significantly different at time 0 (i.e., upon opening), which suggests that the operational use does not affect the function of the TATP POCR system. This information provides pivotal evidence for explosives detection canine handlers or trainers who utilize the TATP POCR.
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Affiliation(s)
- Emily Cropper
- Research and Support Unit, Visiting Scientist Program, Federal Bureau of Investigation Laboratory Division, Quantico, Virginia, USA
| | - Paige Riley
- Research and Support Unit, Visiting Scientist Program, Federal Bureau of Investigation Laboratory Division, Quantico, Virginia, USA
| | - Alison G Simon
- School of Forensic Sciences, Oklahoma State University - Center for Health Sciences, Tulsa, Oklahoma, USA
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2
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Ramos MT, Chang G, Wilson C, Gilbertie J, Krieg J, Parvizi J, Chen AF, Otto CM, Schaer TP. Dogs can detect an odor profile associated with Staphylococcus aureus biofilms in cultures and biological samples. Front Allergy 2024; 5:1275397. [PMID: 38414670 PMCID: PMC10896932 DOI: 10.3389/falgy.2024.1275397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 01/23/2024] [Indexed: 02/29/2024] Open
Abstract
Introduction The study investigated the utilization of odor detection dogs to identify the odor profile of Staphylococcus aureus (S. aureus) biofilms in pure in vitro samples and in in vivo biosamples from animals and humans with S. aureus periprosthetic joint infection (PJI). Biofilms form when bacterial communities aggregate on orthopedic implants leading to recalcitrant infections that are difficult to treat. Identifying PJI biofilm infections is challenging, and traditional microbiological cultures may yield negative results even in the presence of clinical signs. Methods Dogs were trained on pure in vitro S. aureus biofilms and tested on lacrimal fluid samples from an in vivo animal model (rabbits) and human patients with confirmed S. aureus PJI. Results The results demonstrated that dogs achieved a high degree of sensitivity and specificity in detecting the odor profile associated with S. aureus biofilms in rabbit samples. Preliminary results suggest that dogs can recognize S. aureus volatile organic compounds (VOCs) in human lacrimal fluid samples. Discussion Training odor detection dogs on in vitro S. aureus, may provide an alternative to obtaining clinical samples for training and mitigates biosecurity hazards. The findings hold promise for culture-independent diagnostics, enabling early disease detection, and improved antimicrobial stewardship. In conclusion, this research demonstrates that dogs trained on in vitro S. aureus samples can identify the consistent VOC profile of PJI S. aureus biofilm infections. The study opens avenues for further investigations into a retained VOC profile of S. aureus biofilm infection. These advancements could revolutionize infectious disease diagnosis and treatment, leading to better patient outcomes and addressing the global challenge of antimicrobial resistance.
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Affiliation(s)
- Meghan T Ramos
- Penn Vet Working Dog Center, Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Gerard Chang
- Department of Orthopaedics, Geisel School of Medicine at Dartmouth, Lebanon, NH, United States
| | - Clara Wilson
- Penn Vet Working Dog Center, Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Jessica Gilbertie
- Center for One Health Research Edward Via College of Osteopathic Medicine, Blacksburg, VA, United States
| | - James Krieg
- Rothman Orthopaedic Institute, Philadelphia, PA, United States
| | - Javad Parvizi
- Rothman Orthopaedic Institute, Philadelphia, PA, United States
| | - Antonia F Chen
- Department of Orthopaedics, Harvard Medical School, Brigham and Women's Hospital, Harvard University, Boston, MA, United States
| | - Cynthia M Otto
- Penn Vet Working Dog Center, Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Thomas P Schaer
- Department of Clinical Studies New Bolton Center, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA, United States
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Katilie CJ, DeGreeff LE, Sharpes CE, Best EM, Buckley PE, Gadberry JD, Maughan MN. Evaluation of canine training aids containment for homemade explosive and components by headspace analysis and canine testing. J Forensic Sci 2023; 68:2021-2036. [PMID: 37691017 DOI: 10.1111/1556-4029.15368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 08/12/2023] [Accepted: 08/15/2023] [Indexed: 09/12/2023]
Abstract
While canines are most commonly trained to detect traditional explosives, such as nitroaromatics and smokeless powders, homemade explosives (HMEs), such as fuel-oxidizer mixtures, are arguably a greater threat. As such, it is imperative that canines are sufficiently trained in the detection of such HMEs. The training aid delivery device (TADD) is a primary containment device that has been used to house HMEs and HME components for canine detection training purposes. This research assesses the odor release from HME components, ammonium nitrate (AN), urea nitrate (UN), and potassium chlorate (PC), housed in TADDs. Canine odor recognition tests (ORTs) were used with analytical data to determine the detectability of TADDs containing AN, UN, or PC. Headspace analysis by gas chromatography/mass spectrometry (GC/MS) with solid-phase microextraction (SPME) or online cryotrapping were used to measure ammonia or chlorine, as well as other unwanted odorants, emanating from bulk AN, UN, and PC in TADDs over 28 weeks. The analytical data showed variation in the amount of ammonia and chlorine over time, with ammonia from AN and UN decreasing slowly over time and the abundance of chlorine from PC TADDs dependent on the frequency of exposure to ambient air. Even with these variations in odor abundance, canines previously trained to detect bulk explosive HME components were able to detect all three targets in glass and plastic TADDs for at least 18 months after loading. Detection proficiency ranged from 64% to 100% and was not found to be dependent on either age of material.
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Affiliation(s)
| | - Lauryn E DeGreeff
- Formerly of the U.S. Naval Research Laboratory, Washington, District of Columbia, USA
| | | | - Eric M Best
- College of Emergency Preparedness, Homeland Security and Cybersecurity, University of Albany, Albany, New York, USA
| | - Patricia E Buckley
- US Army DEVCOM Chemical Biological Center, Aberdeen Proving Ground, Maryland, USA
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Gauthier QT, Riley P, Simon AG. Toward maintaining canine training aid integrity: Visualizing contamination and testing storage materials for a non-hazardous canine training aid. J Forensic Sci 2023; 68:898-907. [PMID: 36991527 DOI: 10.1111/1556-4029.15232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 02/07/2023] [Accepted: 02/07/2023] [Indexed: 03/31/2023]
Abstract
Contamination of canine training aids is a pervasive issue that may lead to incorrect canine discrimination of target odors. It is therefore important to properly store training materials to maintain their integrity and efficiency. First, this study demonstrated the potential for contamination using GloGerm™ as a proxy for odor/particulate transfer. Then, eight types of containers were evaluated to determine (1) the ability to prevent odor permeation and (2) the likelihood of maintaining the ab/adsorbed odor. Lastly, a longitudinal study evaluated how the permeation of the target odor changed over time. Analysis occurred using a direct analysis in real-time mass spectrometer (DART-MS) to detect triacetone triperoxide (TATP) from the non-hazardous canine training aid known as the polymer odor capture-and-release (POCR) system. Results showed that Mylar and Opsak bags were most effective for short-term storage, maintaining low levels of ab/adsorption. Over time, the amount of TATP permeating through the primary containers and collecting in a secondary container (i.e., outer packaging) increased at 1 week and decreased thereafter (up to 4 months). The amount of TATP collecting in the primary containers, however, increased up to 1 month and decreased thereafter.
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Affiliation(s)
- Quentin T Gauthier
- Research and Support Unit, Visiting Scientist Program, Federal Bureau of Investigation Laboratory Division, Quantico, Virginia, USA
| | - Paige Riley
- Research and Support Unit, Visiting Scientist Program, Federal Bureau of Investigation Laboratory Division, Quantico, Virginia, USA
| | - Alison G Simon
- School of Forensic Sciences, Oklahoma State University - Center for Health Sciences, Tulsa, Oklahoma, USA
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Meller S, Al Khatri MSA, Alhammadi HK, Álvarez G, Alvergnat G, Alves LC, Callewaert C, Caraguel CGB, Carancci P, Chaber AL, Charalambous M, Desquilbet L, Ebbers H, Ebbers J, Grandjean D, Guest C, Guyot H, Hielm-Björkman A, Hopkins A, Kreienbrock L, Logan JG, Lorenzo H, Maia RDCC, Mancilla-Tapia JM, Mardones FO, Mutesa L, Nsanzimana S, Otto CM, Salgado-Caxito M, de los Santos F, da Silva JES, Schalke E, Schoneberg C, Soares AF, Twele F, Vidal-Martínez VM, Zapata A, Zimin-Veselkoff N, Volk HA. Expert considerations and consensus for using dogs to detect human SARS-CoV-2-infections. Front Med (Lausanne) 2022; 9:1015620. [PMID: 36569156 PMCID: PMC9773891 DOI: 10.3389/fmed.2022.1015620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Accepted: 11/17/2022] [Indexed: 12/13/2022] Open
Affiliation(s)
- Sebastian Meller
- Department of Small Animal Medicine & Surgery, University of Veterinary Medicine Hannover, Hanover, Germany,*Correspondence: Sebastian Meller,
| | | | - Hamad Khatir Alhammadi
- International Operations Department, Ministry of Interior of the United Arab Emirates, Abu Dhabi, United Arab Emirates
| | - Guadalupe Álvarez
- Faculty of Veterinary Science, University of Buenos Aires, Buenos Aires, Argentina
| | - Guillaume Alvergnat
- International Operations Department, Ministry of Interior of the United Arab Emirates, Abu Dhabi, United Arab Emirates
| | - Lêucio Câmara Alves
- Department of Veterinary Medicine, Federal Rural University of Pernambuco, Recife, Brazil
| | - Chris Callewaert
- Center for Microbial Ecology and Technology, Department of Biotechnology, Ghent University, Ghent, Belgium
| | - Charles G. B. Caraguel
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, SA, Australia
| | - Paula Carancci
- Faculty of Veterinary Science, University of Buenos Aires, Buenos Aires, Argentina
| | - Anne-Lise Chaber
- School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, SA, Australia
| | - Marios Charalambous
- Department of Small Animal Medicine & Surgery, University of Veterinary Medicine Hannover, Hanover, Germany
| | - Loïc Desquilbet
- École Nationale Vétérinaire d’Alfort, IMRB, Université Paris Est, Maisons-Alfort, France
| | | | | | - Dominique Grandjean
- École Nationale Vétérinaire d’Alfort, Université Paris-Est, Maisons-Alfort, France
| | - Claire Guest
- Medical Detection Dogs, Milton Keynes, United Kingdom
| | - Hugues Guyot
- Clinical Department of Production Animals, Fundamental and Applied Research for Animals & Health Research Unit, Faculty of Veterinary Medicine, University of Liège, Liège, Belgium
| | - Anna Hielm-Björkman
- Department of Equine and Small Animal Medicine, University of Helsinki, Helsinki, Finland
| | - Amy Hopkins
- Medical Detection Dogs, Milton Keynes, United Kingdom
| | - Lothar Kreienbrock
- Department of Biometry, Epidemiology and Information Processing, University of Veterinary Medicine Hannover, Hanover, Germany
| | - James G. Logan
- Department of Disease Control, London School of Hygiene and Tropical Medicine, London, United Kingdom,Arctech Innovation, The Cube, Dagenham, United Kingdom
| | - Hector Lorenzo
- Faculty of Veterinary Science, University of Buenos Aires, Buenos Aires, Argentina
| | | | | | - Fernando O. Mardones
- Escuela de Medicina Veterinaria, Facultad de Agronomía e Ingeniería Forestal and Facultad de Ciencias Biológicas y Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Leon Mutesa
- Center for Human Genetics, College of Medicine and Health Sciences, University of Rwanda, Kigali, Rwanda,Rwanda National Joint Task Force COVID-19, Kigali, Rwanda
| | | | - Cynthia M. Otto
- Penn Vet Working Dog Center, Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Marília Salgado-Caxito
- Escuela de Medicina Veterinaria, Facultad de Agronomía e Ingeniería Forestal and Facultad de Ciencias Biológicas y Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | | | | | - Esther Schalke
- Bundeswehr Medical Service Headquarters, Koblenz, Germany
| | - Clara Schoneberg
- Department of Biometry, Epidemiology and Information Processing, University of Veterinary Medicine Hannover, Hanover, Germany
| | - Anísio Francisco Soares
- Department of Animal Morphology and Physiology, Federal Rural University of Pernambuco, Recife, Brazil
| | - Friederike Twele
- Department of Small Animal Medicine & Surgery, University of Veterinary Medicine Hannover, Hanover, Germany
| | - Victor Manuel Vidal-Martínez
- Laboratorio de Parasitología y Patología Acuática, Departamento de Recursos del Mar, Centro de Investigación y de Estudios Avanzados del IPN Unidad Mérida, Mérida, Yucatán, Mexico
| | - Ariel Zapata
- Faculty of Veterinary Science, University of Buenos Aires, Buenos Aires, Argentina
| | - Natalia Zimin-Veselkoff
- Escuela de Medicina Veterinaria, Facultad de Agronomía e Ingeniería Forestal and Facultad de Ciencias Biológicas y Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Holger A. Volk
- Department of Small Animal Medicine & Surgery, University of Veterinary Medicine Hannover, Hanover, Germany,Center for Systems Neuroscience Hannover, Hanover, Germany
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Gokool VA, Crespo-Cajigas J, Mallikarjun A, Collins A, Kane SA, Plymouth V, Nguyen E, Abella BS, Holness HK, Furton KG, Johnson ATC, Otto CM. The Use of Biological Sensors and Instrumental Analysis to Discriminate COVID-19 Odor Signatures. Biosensors (Basel) 2022; 12:1003. [PMID: 36421122 PMCID: PMC9688190 DOI: 10.3390/bios12111003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 11/01/2022] [Accepted: 11/08/2022] [Indexed: 05/27/2023]
Abstract
The spread of SARS-CoV-2, which causes the disease COVID-19, is difficult to control as some positive individuals, capable of transmitting the disease, can be asymptomatic. Thus, it remains critical to generate noninvasive, inexpensive COVID-19 screening systems. Two such methods include detection canines and analytical instrumentation, both of which detect volatile organic compounds associated with SARS-CoV-2. In this study, the performance of trained detection dogs is compared to a noninvasive headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) approach to identifying COVID-19 positive individuals. Five dogs were trained to detect the odor signature associated with COVID-19. They varied in performance, with the two highest-performing dogs averaging 88% sensitivity and 95% specificity over five double-blind tests. The three lowest-performing dogs averaged 46% sensitivity and 87% specificity. The optimized linear discriminant analysis (LDA) model, developed using HS-SPME-GC-MS, displayed a 100% true positive rate and a 100% true negative rate using leave-one-out cross-validation. However, the non-optimized LDA model displayed difficulty in categorizing animal hair-contaminated samples, while animal hair did not impact the dogs' performance. In conclusion, the HS-SPME-GC-MS approach for noninvasive COVID-19 detection more accurately discriminated between COVID-19 positive and COVID-19 negative samples; however, dogs performed better than the computational model when non-ideal samples were presented.
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Affiliation(s)
- Vidia A. Gokool
- Global Forensic and Justice Center, Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Janet Crespo-Cajigas
- Global Forensic and Justice Center, Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Amritha Mallikarjun
- Penn Vet Working Dog Center, Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Amanda Collins
- Penn Vet Working Dog Center, Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Sarah A. Kane
- Penn Vet Working Dog Center, Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Victoria Plymouth
- Penn Vet Working Dog Center, Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Elizabeth Nguyen
- Penn Vet Working Dog Center, Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Benjamin S. Abella
- Department of Emergency Medicine and Penn Acute Research Collaboration, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Howard K. Holness
- Global Forensic and Justice Center, Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Kenneth G. Furton
- Global Forensic and Justice Center, Department of Chemistry and Biochemistry, Florida International University, Miami, FL 33199, USA
| | - Alan T. Charlie Johnson
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Cynthia M. Otto
- Penn Vet Working Dog Center, Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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7
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Gauthier QT, Riley P, Simon AG. Permeation of human scent through laboratory examination gloves. J Forensic Sci 2022; 67:2308-2320. [PMID: 35968683 DOI: 10.1111/1556-4029.15123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 07/25/2022] [Accepted: 08/04/2022] [Indexed: 11/28/2022]
Abstract
It is generally accepted in the canine detection industry that a barrier (such as a glove) should be used between a human and evidence or canine training aids in order to prevent contamination and cross-contamination as well as protect the handler from hazardous materials. However, no studies exist evaluating this assumption. Further, there is no published literature examining the different types of gloves for their utility in handling evidence or training materials used in canine detection work. This study was the first of its kind to address these gaps in the literature. First, GloGerm™ was used as a proxy for human scent and odor(s)/particulate(s) to visualize potential contamination. Then, three types of gloves (nitrile, two layers of nitrile, latex, and polyethylene) were tested for the permeation of human scent using furfural as a proof of concept, followed by pooled human sweat. Finally, the inherent odor of each glove type was identified. Two analytical techniques were used simultaneously as static and standoff dynamic detection systems, respectively: solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) and direct analysis in real time-mass spectrometry (DART-MS). Using a double layer of nitrile gloves was the most effective in preventing furfural permeation from the analytical standard, while a single layer of nitrile prevented furfural from permeating from human sweat up to 2 h. Polyethylene gloves allowed the highest amount of furfural permeation but had no inherent odor detected. Headspace analysis detected two compounds for nitrile gloves and four compounds for latex gloves, but the nitrile compounds had a higher relative abundance.
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Affiliation(s)
- Quentin T Gauthier
- Research and Support Unit, Visiting Scientist Program, Federal Bureau of Investigation Laboratory Division, Quantico, Virginia, USA
| | - Paige Riley
- Research and Support Unit, Visiting Scientist Program, Federal Bureau of Investigation Laboratory Division, Quantico, Virginia, USA
| | - Alison G Simon
- School of Forensic Sciences, Oklahoma State University - Center for Health Sciences, Tulsa, Oklahoma, USA
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8
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DeChant MT, Bunker PC, Hall NJ. Stimulus Control of Odorant Concentration: Pilot Study of Generalization and Discrimination of Odor Concentration in Canines. Animals (Basel) 2021; 11:ani11020326. [PMID: 33525503 PMCID: PMC7912023 DOI: 10.3390/ani11020326] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 01/18/2021] [Accepted: 01/19/2021] [Indexed: 11/25/2022] Open
Abstract
Simple Summary Dogs are deployed worldwide for detection tasks, but little is known about how they spontaneously generalize between concentration variations of their trained odor. This study found that dogs spontaneously generalized within a 10-fold concentration range lower than the training stimulus. Further, dogs could be trained to discriminate between concentrations within that 10-fold range. However, discrimination training did not affect dogs’ spontaneous generalization to the odor concentration unless discrimination training occurred in compound with generalization testing, suggesting that relative stimulus control of the target and non-target concentrations might be important in determining whether dogs will respond. Abstract Despite dogs’ widespread use as detection systems, little is known about how dogs generalize to variations of an odorant’s concentration. Further, it is unclear whether dogs can be trained to discriminate between similar concentration variations of an odorant. Four dogs were trained to an odorant (0.01 air dilution of isoamyl acetate) in an air-dilution olfactometer, and we assessed spontaneous generalization to a range of concentrations lower than the training stimulus (Generalization Test 1). Dogs generalized to odors within a 10-fold range of the training odorant. Next, we conducted discrimination training to suppress responses to concentrations lower than a concentration dogs showed initial responding towards in Generalization Test 1 (0.0025 air dilution). Dogs successfully discriminated between 0.0025 and 0.01, exceeding 90% accuracy. However, when a second generalization test was conducted (Generalization Test 2), responding at the 0.0025 concentration immediately recovered and was no different than in Generalization Test 1. Dogs were then tested in another generalization test (Compound Discrimination and Generalization) in which generalization probes were embedded within discrimination trials, and dogs showed suppression of responding to the 0.0025 concentration and lower concentrations in this preparation. These data suggest dogs show limited spontaneous generalization across odor concentration and that dogs can be trained to discriminate between similar concentrations of the same odorant. Stimulus control, however, may depend on the negative stimulus, suggesting olfactory concentration generalization may depend on relative stimulus control. These results highlight the importance of considering odor concentration as a dimension for generalization in canine olfactory research.
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Affiliation(s)
- Mallory T. DeChant
- Department of Food and Animal Sciences, Texas Tech University, Lubbock, TX 79409, USA;
| | | | - Nathaniel J. Hall
- Department of Food and Animal Sciences, Texas Tech University, Lubbock, TX 79409, USA;
- Correspondence:
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Simon A, Lazarowski L, Singletary M, Barrow J, Van Arsdale K, Angle T, Waggoner P, Giles K. A Review of the Types of Training Aids Used for Canine Detection Training. Front Vet Sci 2020; 7:313. [PMID: 32596267 PMCID: PMC7301692 DOI: 10.3389/fvets.2020.00313] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 05/06/2020] [Indexed: 12/04/2022] Open
Abstract
The canine detection community is a diverse one, ranging from scientific fields such as behavior, genetics, veterinary medicine, chemistry, and biology to applications in law enforcement, military, medicine, and agricultural/environmental detection. This diversity has allowed for a flourishing and innovative community, yet it has also led to little acceptance and agreement on terminology. This is especially true when discussing the variety of training aids used in olfactory-based exercises. In general, authentic materials and pseudo-scents are the most commonly discussed, with the former accepted widely for training and certification, and the latter more often disregarded. However, as advances are made in the creation of training materials, alternative training aids are being introduced that do not fit into either of these categories. The misconceptions surrounding how these alternative training aids are manufactured has led to confusion on their classification, and therefore their reliance as an effective tool. This manuscript will review the existing language surrounding canine training aids, address relevant research revealing effectiveness, and clarify the different types based on their manufacture, chemical nature, and fundamental function.
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Affiliation(s)
- Alison Simon
- AGS Forensics, LLC, Washington, DC, United States
| | - Lucia Lazarowski
- Canine Performance Sciences, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
| | - Melissa Singletary
- Canine Performance Sciences, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
| | - Jason Barrow
- Federal Bureau of Investigation Laboratory, Quantico, VA, United States
| | - Kelly Van Arsdale
- Federal Bureau of Investigation Laboratory, Quantico, VA, United States
| | - Thomas Angle
- Canine Performance Sciences, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
| | - Paul Waggoner
- Canine Performance Sciences, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
| | - Kathleen Giles
- Giles Consulting, LLC, Huntington Beach, CA, United States
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Gottwald T, Poole G, McCollum T, Hall D, Hartung J, Bai J, Luo W, Posny D, Duan YP, Taylor E, da Graça J, Polek M, Louws F, Schneider W. Canine olfactory detection of a vectored phytobacterial pathogen, Liberibacter asiaticus, and integration with disease control. Proc Natl Acad Sci U S A 2020; 117:3492-501. [PMID: 32015115 DOI: 10.1073/pnas.1914296117] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Exotic infectious pathogens, like citrus huanglongbing (HLB), are increasingly introduced into agrosystems. Early detection is the key to mitigating their destructive effects. Human visual assessment is insufficiently sensitive to detect new plant infections in a responsive timeframe, and molecular assays are expensive and not easily deployable over large crop landscapes. We turned to detector dogs, an ancient technology, which can rapidly survey large plantings without laborious sample collection or laboratory processing. Dogs detected infections (>99% accuracy) weeks to years prior to visual survey and molecular methods and were highly specific, accurately discriminating target pathogens from other pathogens. Epidemiological models indicated that dogs were more effective and economical than current early detection methods for sustainable disease control. Early detection and rapid response are crucial to avoid severe epidemics of exotic pathogens. However, most detection methods (molecular, serological, chemical) are logistically limited for large-scale survey of outbreaks due to intrinsic sampling issues and laboratory throughput. Evaluation of 10 canines trained for detection of a severe exotic phytobacterial arboreal pathogen, Candidatus Liberibacter asiaticus (CLas), demonstrated 0.9905 accuracy, 0.8579 sensitivity, and 0.9961 specificity. In a longitudinal study, cryptic CLas infections that remained subclinical visually were detected within 2 wk postinfection compared with 1 to 32 mo for qPCR. When allowed to interrogate a diverse range of in vivo pathogens infecting an international citrus pathogen collection, canines only reacted to Liberibacter pathogens of citrus and not to other bacterial, viral, or spiroplasma pathogens. Canines trained to detect CLas-infected citrus also alerted on CLas-infected tobacco and periwinkle, CLas-bearing psyllid insect vectors, and CLas cocultured with other bacteria but at CLas titers below the level of molecular detection. All of these observations suggest that canines can detect CLas directly rather than only host volatiles produced by the infection. Detection in orchards and residential properties was real time, ∼2 s per tree. Spatiotemporal epidemic simulations demonstrated that control of pathogen prevalence was possible and economically sustainable when canine detection was followed by intervention (i.e., culling infected individuals), whereas current methods of molecular (qPCR) and visual detection failed to contribute to the suppression of an exponential trajectory of infection.
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Angle C, Waggoner LP, Ferrando A, Haney P, Passler T. Canine Detection of the Volatilome: A Review of Implications for Pathogen and Disease Detection. Front Vet Sci 2016; 3:47. [PMID: 27446935 PMCID: PMC4919317 DOI: 10.3389/fvets.2016.00047] [Citation(s) in RCA: 71] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 06/03/2016] [Indexed: 02/01/2023] Open
Abstract
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.
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Affiliation(s)
- Craig Angle
- Canine Performance Sciences Program, College of Veterinary Medicine, Auburn University , Auburn, AL , USA
| | - Lowell Paul Waggoner
- Canine Performance Sciences Program, College of Veterinary Medicine, Auburn University , Auburn, AL , USA
| | - Arny Ferrando
- Center for Translational Research in Aging and Longevity, University of Arkansas for Medical Sciences , Little Rock, AR , USA
| | - Pamela Haney
- Canine Performance Sciences Program, College of Veterinary Medicine, Auburn University , Auburn, AL , USA
| | - Thomas Passler
- Department of Clinical Sciences, College of Veterinary Medicine, Auburn University , Auburn, AL , USA
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