Identifying Suitable Detection Dogs

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Accepted Manuscript

Title: Identifying suitable detection dogs

Authors: La Toya J. Jamieson, Greg S. Baxter, Peter J. Murray

PII: S0168-1591(17)30187-9 DOI: http://dx.doi.org/doi:10.1016/j.applanim.2017.06.010 Reference: APPLAN 4481

To appear in: APPLAN

Received date: 27-2-2017 Revised date: 14-6-2017 Accepted date: 15-6-2017

Please cite this article as: Jamieson, La Toya J., Baxter, Greg S., Murray, Peter J., Identifying suitable detection dogs.Applied Animal Behaviour Science http://dx.doi.org/10.1016/j.applanim.2017.06.010

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La Toya J. Jamieson

Greg S. Baxter

Peter J. Murray

Affiliation for all authors: The University of Queensland, School of Agriculture and Food Sciences, Gatton campus 4343, Australia.

Authors’ e-mail addresses (in order as above): [email protected] [email protected] [email protected]

Corresponding author’s contact details:

La Toya Jamieson

Phone: +61404 495 423

E-mail: [email protected]

Address: Wildlife Science Unit, Faculty of Science

The University of Queensland, Gatton Campus

Gatton, Queensland 4343 Australia

Highlights

 Knowledge of favourable detection dog characteristics may improve working dog selection.

 Commonly utilised dog breeds may not produce the most suitable detection dog.

 Due to individual variation, a dog should not be solely chosen based on their breed.

Abstract

Domestic dogs (Canis lupus familiaris) are versatile resources for humans due to a number of their physical and behavioural characteristics. Because of dogs’ olfactory acuity they have been used to detect cryptic or concealed items such as narcotics, explosives and wildlife. However, there is a wide variation in performance. This variation is often not correlated with their breed and has not been rigorously tested. Little research has compared dog breeds for their suitability as detection dogs, and even fewer studies have concluded which characteristics should be selected. This is important considering the number of dogs produced for detection work. This paper has collated the scientific literature to present important behavioural and physical traits, and traits which should be avoided, in detection dogs. The important traits include: highly play motivated; high level of cooperativeness with their handler; boldness; obedience yet independence when off-leash; and high athleticism. Although wildlife detection dogs are this paper’s focus, these proposed traits are relevant in any detection field.

Keywords: Detection dogs, dog breeds, breed variation, working performance.

1.0 Introduction

Behavioural and performance differences between breeds of dogs (Canis lupus familiaris) can be a controversial topic (Fadel et al., 2016). Behavioural differences between breeds are often inappropriately generalised, however, they are a distinct group of genetic units (Ostrander and Wayne,

2005; Clarke et al., 2013). Whilst it has been emphasised that each breed has specific behavioural characteristics, studies highlight the variation amongst individuals within breeds (Mehrkam and

Wynne, 2014). This variability is likely a result of the change in dog breeding priorities, from breeding for abilities to breeding for appearance (Mirkó et al., 2012). Domestic dogs have traditionally been utilised by humans due to their ability to perform specific working roles, including guarding, hunting, herding and detection (Rooney and Bradshaw, 2004; Serpell and Duffy, 2014).

Dogs are a highly versatile detection tool and have been utilised in over 30 different tasks (Lorenzo et

1 al., 2003; Hall et al., 2014). As detection dogs are a modern phenomenon no dog has been bred solely for this purpose (Rooney and Bradshaw, 2004).

Both physical and behavioural traits are important when selecting working dogs (Coppinger and

Coppinger, 2001; McGarrity et al., 2016). The variation between dogs’ working performances can be attributed to behavioural differences, emphasising the importance of selecting a dog that is physically capable and behaviourally suited to detection work (Slabbert and Odendaal, 1999; Svartberg and

Forkman, 2002; Rooney et al., 2007; Sinn et al., 2010). When selecting a detection dog certain behavioural and physical characteristics are typically desired. This has resulted in certain breeds being favoured for detection work. The current lack of breed comparative studies and the variation within each breed provides a challenge when selecting a suitable detection dog (Rooney and Bradshaw,

2004; Jezierski et al., 2014). If only individuals from one or two breeds are evaluated for their working potential, as is common in Military working dog programs (Moore et al., 2001; Sinn et al.,

2010), this may restrict the detection program’s success. Breeders are not always aware of important characteristics of successful detection dogs, due to poor communication with the dog-handlers

(Rocznik et al., 2015). Once a working program is established and traditions are formed, there is often minimal feedback received from the dog-handlers in relation to choosing breeding dogs (Rocznik et al., 2015). To maximise the efficiency of identifying suitable detection dog candidates, important physical and behavioural traits for specific detection tasks must be determined.

Wildlife detection dogs are a unique category of detection dogs trained to locate wildlife scats, carcasses or live animals (Hurt and Smith, 2009). Whilst Beebe et al. (2016) have proposed certain important wildlife detection dog traits, commonly used dog breeds and their suitability for detection work has not been discussed. Irrespective of the breed selected, a dog’s temperament should always be gauged prior to choosing it for detection work (Graham and Gosling, 2009; McGarrity et al.,

2016).

Characteristics of the most suitable individual for detection work, with a focus on wildlife detection, will be explored here. Depending on dog breeders’ genetic selection criteria, breeds which were

2 typically chosen for traditional traits and functions (e.g. tracking) may no longer possess such qualities (Adamkiewicz et al., 2013). Continually selecting the same dog breeds, without inspecting other breeds, may reduce the effectiveness of detection dog programs. This review will discuss the physical and behavioural characteristics of a suitable detection dog; commonly used dog breeds for detection, and the variation within these breeds.

2.0 Detection dog traits

2.1 Ideal detection dog traits Most detection dogs to date have been herding, hunting or sporting breeds (Brownell and Marsolais,

2002). A detection dog should be athletic and trainable, to ensure the dog is physically capable of completing the work, whilst also having desirable motivations (Brownell and Marsolais, 2002).

Differences between dog breed physical characteristics undoubtedly influence their skills and capabilities (Coppinger and Coppinger, 2001). Behavioural traits have also been investigated to improve animal welfare, and dog training and management (Svartberg, 2002; Clarke et al., 2013;

McGarrity et al., 2016). There are multiple physical and behavioural traits which are important for detection dogs to possess. Choosing dogs with the following traits, gleaned from the literature, should increase both the dog’s suitability for detection work and their working performance.

Speed is important in any working dog field, ensuring working efficiency (Helton, 2010). Detection dogs should work quickly, whilst not missing the intended targets nor exhausting themselves prematurely (Jezierski et al., 2014). In difficult terrain detection dogs should be agile, with exceptional stamina, allowing them to traverse the terrain (Rebmann et al., 2000; Hurt and Smith,

2009). Medium-built dogs with suitably long legs are preferable, which is also beneficial if the dog becomes injured and needs to be carried (Hurt and Smith, 2009). Medium-built dogs, with shorter coats, can also be advantageous for heat tolerance (Chesney, 1997; Hurt and Smith, 2009). Large dog breeds retain too much body heat and small dog breeds retain too little (Coppinger and Coppinger,

2001). Heat-tolerant dogs are able to work more efficiently with fewer breaks, without the risk of overheating, which is not only detrimental to the dog’s working performance but can be fatal (Hurt

3 and Smith, 2009). The choice of a dog’s build and size is therefore a reflection of the dog’s working environment (Rebmann et al., 2000).

In the following sections the term ‘drive’ and its importance in relation to detection dogs will be discussed. A dog’s drive is their impulse or motivation to perform a behaviour or action (Brownell and Marsolais, 2002). This concept is not current in behavioural science; however, it is widely and currently used in working dog science (Beebe et al., 2016; Minhinnick et al., 2016). Due to its importance in working dog science, the term ‘drive’ will be used. It should be highlighted that a dog’s

‘drive’ or motivation can be influenced by external factors (e.g. environmental), and therefore can be modified over time.

Detection dog handlers typically select working dogs who have strong motivational drives (Beebe et al., 2016). Motivators which are important during detection dog selection are play-, prey-, and hunt- drives (Maejima et al., 2007; Hurt and Smith, 2009; Reed et al., 2011; Beebe et al., 2016; Minhinnick et al., 2016). A dog’s play-drive is the desire to be entertained, which ensures the dog values a toy or play reward in exchange for performing a particular behaviour (Cablk and Heaton, 2006; Hurt and

Smith, 2009; Duggan et al., 2011). A detection dog will ideally be highly play motivated, to the point of obsession (Rebmann et al., 2000; Hurt and Smith, 2009; Beebe et al., 2016; Minhinnick et al.,

2016). This will ensure the dog is willing to perform hundreds of repetitions to receive their toy, which is crucial for training and work (Hurt and Smith, 2009).

A dog’s desire to search is referred to as their hunt-drive and is important for sustaining motivation

(Cablk and Heaton, 2006; Hurt and Smith, 2009). This motivation to search is crucial for dogs during surveys where the work is fatiguing and target odours are minimal (Cablk and Heaton, 2006; Hurt and

Smith, 2009; McGarrity et al., 2016). A dog’s prey-drive is their desire to chase and kill (Hurt and

Smith, 2009; Minhinnick et al., 2016). Whilst this may not be problematic for a drug detection dog which only works indoors, a wildlife detection dog with an uncontrolled high prey-drive can be catastrophic (Cablk and Heaton, 2006; Hurt and Smith, 2009; Beebe et al., 2016; Minhinnick et al.,

2016). Ideally a detection dog would not be motivated to chase or kill another animal, which would

4 minimise the risk to both wildlife and the dog (Cablk and Heaton, 2006; Hurt and Smith, 2009; Beebe et al., 2016; Minhinnick et al., 2016). The most suitable definitions and interpretations of these behavioural drives are, however, being challenged in the scientific literature (Minhinnick et al., 2016).

A detection dog must be able to work cooperatively with humans (also known as pack-drive), and follow both visual and auditory cues (Hurt and Smith, 2009; Beebe et al., 2016). This ensures the dog is working efficiently and obediently in the field. Detection dogs should demonstrate minimal aggression to both humans and dogs, allowing for a peaceful home or kennel environment (Rooney and Bradshaw, 2004). Whilst a dog should be willing to work with their handler, a detection dog should have a certain degree of independence when working (Rebmann et al., 2000; Rooney and

Bradshaw, 2004; Hurt and Smith, 2009; Adamkiewicz et al., 2013). This enables them to make their own choices in the field when required. Trained dogs typically look to their handlers for guidance less than untrained dogs, which indicates independence and their problem-solving ability (Prato-Previde et al., 2008; Marshall-Pescini et al., 2009). Caution should be made when selecting an independent individual, with dogs possessing too much independence commonly becoming disobedient (Rebmann et al., 2000). Obedience off-leash, yet a certain degree of independence, is critical especially for the safety of both explosive and wildlife detection dogs (Rebmann et al., 2000; Hurt and Smith, 2009;

Adamkiewicz et al., 2013).

A dog’s ability to adapt to, and cope with, stress-producing stimuli within their environment are important working dog traits (Brownell and Marsolais, 2002; Hurt and Smith, 2009). This coping mechanism is crucial for detection dogs who are frequently exposed to a variety of visual, aural, olfactory and tactile environmental stimuli (Brownell and Marsolais, 2002; Hurt and Smith, 2009).

This is related to not only its breed, but also their training, socialisation, early life experiences and environmental exposure (Brownell and Marsolais, 2002; Hurt and Smith, 2009).

2.2 Undesirable detection dog traits Whilst fear and anxious responses are both crucial for survival (Ohl et al., 2008), they are not ideal for detection dogs (van Rooy et al., 2014). Fearful dogs are undesirable due to the amount of stimuli in their working environment (Graham and Gosling, 2009; Adamkiewicz et al., 2013). Typically dogs

5 with poor concentration are also more anxious, providing further reason to reject individuals that are easily distracted (Murphy, 1998). High performing detection dogs typically score higher for boldness in comparison to lower performing dogs (Svartberg, 2002).

An individual dog’s olfactory ability is dictated by a variety of factors, including their breed, anatomy and age (Rauth-Widmann, 2006; Hurt and Smith, 2009). The dog’s nasal cavity contains millions of sensory neurons within the olfactory epithelium (Craven et al., 2010). The dog’s body size influences their olfactory epithelium, with a Fox Terriers’ being ~84 cm2 and a German Shepherds being ~150 cm2 (Rauth-Widmann, 2006). This large epithelium, put simply, means a larger area for sensory neurons (Rauth-Widmann, 2006). More sensory neurons can increase the dog’s olfactory accuracy; however, this alone does not indicate the dog’s working ability (Rauth-Widmann, 2006).

Brachycephalic breeds typically have poor olfactory abilities, due to the minimal space allowing for the olfactory epithelium to expand within their noses (Rauth-Widmann, 2006; Bartels et al., 2015).

Brachycephalic breeds also have notably less olfactory cells, thereby reducing their olfactory sensitivity (Rauth-Widmann, 2006). Breeds with elongated noses (mesocephalic breeds) have more olfactory receptor cells, allowing them to identify and retain more scent (Craven et al., 2007; Abney,

2009). Brachycephalic breeds also typically have breathing issues, resulting in less oxygen provision to the brain causing the dogs to tire easily (Rauth-Widmann, 2006; Packer et al., 2012; Bartels et al.,

2015). Brachycephalic breeds should therefore be avoided when selecting a detection dog.

Even a physically and behaviourally ideal detection dog is not suitable for field work if it is unhealthy. Breeds which have common health issues, such as German Shepherds and Bloodhounds with hip and elbow dysplasia, may not be the most suitable candidates (Palika, 2007). Through gene analysis, however, breeding programs are now concentrating on reducing these common health issues within breeds (Janutta et al., 2006; Fels and Distl, 2014). A dog’s breed is also a factor which influences their longevity (Fleming et al., 2011). This is demonstrated in the variation in longevity between breeds; with Great Danes having an average life expectancy of 6.5 years, in comparison to

Jack Russell Terriers of 14 - 16 years (Palika, 2007; Adams et al., 2010). A dog’s body weight and

6 sexual entirety is also correlated to longevity, with smaller dog breeds and neutered individuals typically living longer (Moore et al., 2001; Galis et al., 2007; Greer et al., 2007; Adams et al., 2010).

Neutering will also decrease distractibility, roaming and aggressive tendencies (Hart and Eckstein,

1997; Maejima et al., 2007).

3.0 Selecting detection dogs

There is commonly performance variation in any working dog environment (Brownell and Marsolais,

2002). Certain dog and handler teams consistently perform to a high standard, both in accuracy and efficiency (Brownell and Marsolais, 2002). The success or failure of these teams can often be traced to the dog’s selection (Brownell and Marsolais, 2002).

There are multiple screening tests which can evaluate and indicate a dog’s future working performance (Brownell and Marsolais, 2002). However, there is a lack of uniformity regarding screening tests amongst the working dog community (Brownell and Marsolais, 2002; Early et al.,

2014). Certain screening tests may be given too much weight for their reliability and potential to indicate a dog’s working potential (Brownell and Marsolais, 2002). Screening tests should be completed prior to selecting dogs for work, however, these tests should not be the sole indicator of a dog’s potential. Any behavioural or trait evaluation must be objective, reliable, meaningful and repeatable (Wilsson and Sundgren, 1997). It would be of great benefit to the canine research and behaviour community for testing techniques to be standardised, allowing for results to be pooled and studies compared (Early et al., 2014; van Rooy et al., 2014).

The Dog Mentality Assessment is commonly used as a behavioural test for dogs, with the results being comparable to the dog owner’s questionnaire responses (Serpell and Hsu, 2005; Svartberg,

2005). This assessment measures the dog’s sociability, playfulness, fearlessness and boldness, through the use of multiple behavioural assessments (Svartberg, 2005). These results are, however, greatly influenced by external factors, such as the scoring judge (Ruefenacht et al., 2002; Saetre et al., 2006).

Phenotyping, the recording and analysis of phenotypes, is used in behavioural studies through the use of owner questionnaires, battery testing and observation studies (van Rooy et al., 2014). A commonly

7 used testing assessment is the behavioural test battery (Jones and Gosling, 2005), where dogs’ reactions are gauged when they’re exposed to specific situations and stimuli (Svartberg and Forkman,

2002; Svartberg, 2002, 2005; Serpell and Hsu, 2005). Similarly ad hoc observational tests occur in uncontrolled environments, where the stimulus is naturally occurring (Goddard and Beilharz 1984;

Mirkó et al., 2012). These tests can be used to determine commonly demonstrated traits in a naturalistic environment, allowing for conclusions about a dog’s behavioural patterns and temperament to be made (Goddard and Beilharz, 1984; Murphy, 1995, 1998; Jones and Gosling,

2005). For phenotyping to be useful it must be sensitive, reliable and objective (van Rooy et al.,

2014). Whilst observational studies can provide a wealth of data, they are commonly less used, due to their high time and financial costs (van Rooy et al., 2014).

A major difficulty with behavioural studies has been measuring and defining certain behaviours, along with how they are expressed (van Rooy et al., 2014). Improved methods for measuring dog behaviour are required (McGarrity et al., 2016). As multiple ways to assess and measure behaviour have been utilised, behavioural studies cannot simply be compared (van Rooy et al., 2014).

International standards in testing protocols for dog behavioural evaluations would therefore be beneficial (van Rooy et al., 2014). With the cost of breeding and rearing dogs in mind, improving behavioural measurements is crucial for improving the efficiency of working dog breeding programs

(McGarrity et al., 2016).

4.0 Commonly used dog breeds for detection work

There are over 400 breeds of dogs displaying a high level of diversity in behaviour and morphology

(Bradshaw et al., 1996; Svartberg, 2006; Serpell and Duffy, 2014). Of these dog breeds, few are chosen to become working detection dogs. Breeds have specific traits that are linked to genetic mutations or to artificial selection by humans (Serpell and Duffy, 2014). For detection dogs, genetic differences, often expressed morphologically, may determine working aptitude (Maejima et al., 2007).

For drug detection, Labrador Retrievers, German Shepherds, Terriers (e.g. Jack Russell) and English

Springer Spaniels are commonly selected breeds (Jezierski et al., 2014). In the United Kingdom the

8 most common breeds for drug and explosives detection are English Springer Spaniels, Labrador

Retrievers, Cross breeds and Border Collies (Rooney and Bradshaw, 2004). Similarly the Labrador

Retriever is the most common narcotics detection dog in Japan (Maejima et al., 2007). Within these narcotic detection programs 30% of dogs that enter narcotics detection training become working detection dogs (Maejima et al., 2007). Whilst this percentage may be a result of strict selection criteria, it still presents a large proportion of dogs that require re-homing. This percentage may also indicate a problem with the chosen dog breed, the methods utilised to select the potential detection dogs, or the training (McGarrity et al., 2016).

4.1 Variation between breeds

Whilst anatomical differences are typically compared between dog breeds, the greatest variation is behavioural (Table 1) (Coppinger and Schneider, 1995). All canine behaviours have a genetic component, which can be breed-specific, such as livestock guarding in Maremmas (van Rooy et al.,

2014). Behaviour is influenced by learning, epigenetics and their surrounding environment (van Rooy et al., 2014). Dog breed variation can typically be explained by their original selection for working use (Helton, 2010; Adamkiewicz et al., 2013). For example sight-hounds, such as Greyhounds, were chosen for their speed, and terriers for their ability to hunt underground (Helton, 2010). These specialist dog breeds were created through continual artificial selection, however, as previously mentioned, there is currently no specialist breed for detection work (Rooney and Bradshaw, 2004).

Dog breeds are perceived as differing in trainability and intelligence, with this perception further complicating identifying a suitable working individual (Rooney and Bradshaw, 2004; Serpell and

Hsu, 2005; Helton, 2009; Ley et al., 2009). Intelligence can be defined as an individual’s ability to learn, perceive and process specified information and apply it in a specific situation (Zhong et al.,

2015). Trainability can be defined as a dog’s ability to learn skills or tasks, and can be measured through evaluating a dog’s performance and speed at learning a task (Helton, 2010; Turcsán et al.,

2011). Coren’s ranking is a ranking of 133 dog breeds for their working intelligence, which should have probably been termed ‘trainability’ (Helton, 2010), based on the opinion of professional obedience judges (208 North American experts in total) (Coren, 1994). According to Coren’s ranking,

9 the most intelligent dogs are Border Collies, Poodles, German Shepherds, Golden Retrievers,

Doberman Pinschers, Shetland Sheepdogs, Labrador Retrievers, Papillons, Rottweilers and Australian

Cattle Dogs (Helton, 2010). The least intelligent breeds are Basset Hounds, Mastiffs, Beagles,

Pekingese, Bloodhounds, Borzoi, Chow Chow, Bulldog, Basenji and Afghan Hounds (Helton, 2010).

As previously stated, this ranking of a breed’s intelligence may be more related to the breed’s trainability (Helton, 2010). Trainability is not the equivalent of an unguided problem-solving ability, thereby demonstrating that trainability isn’t necessarily related to intelligence (Frank and Frank,

1985). This perception of variation amongst dogs’ trainability and intelligence is remarkable, considering the minimal evidence of differences in cognitive abilities between breeds (Gagnon and

Doré, 1992; Pongrácz et al., 2005).

A dog breed’s cooperativeness has influenced how they have been used by humans (Gácsi et al.,

2009). ‘Cooperative worker’ breeds, such as gun and herding dogs, typically work with continual human cues and visual contact (Serpell and Hsu, 2005; Gácsi et al., 2009). ‘Independent worker’ breeds, such as scent-hounds and livestock guarding dogs, typically work with minimal human cues

(Gácsi et al., 2009). As a result, ‘cooperative worker’ breeds are able to respond to human cues more successfully and cooperatively than ‘independent worker’ breeds (Gácsi et al., 2009). This ability to cooperate with humans is invaluable for a detection dog (Gácsi et al., 2009; Hurt and Smith, 2009).

Due to the importance of a dog’s personality when acting as a detector, knowledge regarding their personality is important when selecting and training individuals (Svartberg 2002; Svartberg and

Forkman 2002; McGarrity et al. 2016). Table 1 demonstrates common qualities of five dog types.

It must be acknowledged that dog breeds continue to change over time, with the possibility that they no longer possess the physical or behavioural traits they were originally bred for (van Rooy et al.

2014). Breed specific characteristics are unlikely to be lost, however, unless there is active artificial or natural selection (van Rooy et al. 2014).

4.2 Breed Performance and Comparisons

It is reasonable that, in order for them to become useful tools, detection dogs should be required to have their accuracy validated. Variation amongst performance can be breed related, with certain studies comparing specific breeds’ performances (Rooney and Bradshaw, 2004; Maejima et al., 2007;

Jezierski et al., 2014). This section will explore these comparative studies.

During police drug detection dog testing in Poland, German Shepherds had the highest accuracy and efficiency in comparison to Labrador Retrievers, English Cocker Spaniels and Terriers (Fox, Welsh and Jack Russell) (Jezierski et al., 2014). Terriers had the longest detection times and the highest proportions of false positives (Jezierski et al., 2014). Whilst Terriers demonstrated a relatively poor accuracy rate, their small size can be advantageous, allowing them to investigate confined areas

(Jezierski et al., 2014).

When evaluating the difference between German Shepherds and Labrador Retrievers at the Swedish

Dog Training Centre, a significant difference was reported between the breeds (Wilsson and

Sundgren, 1997). German Shepherds scored significantly higher for ‘defence drive’ and ‘sharpness’

(Wilsson and Sundgren, 1997). Labrador Retrievers scored higher for ‘nerve stability’, ‘hardness’,

‘courage’ and reacted less to gun fire (Wilsson and Sundgren, 1997). Labrador Retrievers were also more cooperative and affable than German Shepherds (Wilsson and Sundgren, 1997). During a similar study Rooney and Bradshaw (2004) created a list of traits and asked dogs-handlers to evaluate their dogs against these traits. For ‘tendency to be distracted’ and ‘stamina’ Labrador Retrievers were significantly further from ideal than English Springer Spaniels (Rooney and Bradshaw, 2004). For

‘food motivation’, Border Collies were significantly closer to ideal than Labrador Retrievers, and were scored closest to ideal for ‘tendency to be distracted’ (Rooney and Bradshaw, 2004). Based solely on this evaluation, Border Collies and English Springer Spaniels would be the most suitable breed for drug/explosives detection work (Rooney and Bradshaw, 2004).

Detection dogs are bred for specific personality traits (McGarrity et al., 2016). Evaluating the outcome of these dog breeding programs can be challenging as even within these specifically selected

11 populations individual variation is prominent (Jones and Gosling, 2005; Graham and Gosling, 2009;

Fratkin et al., 2013). For example when examining a group of 1,310 German Shepherds and 797

Labrador Retrievers at the Swedish Dog Training Centre, 17 German Shepherds and 87 Labrador

Retrievers were successfully trained as detection dogs (Wilsson and Sundgren, 1997). Of the original

1,310 German Shepherds, 788 (60.1%) were rejected as working dogs (e.g. police and detection work), and 147 (11.2%) were euthanised for behavioural reasons (Wilsson and Sundgren, 1997). Of the original 797 Labrador Retrievers, 530 (66.5%) were rejected as working dogs, and 42 (5.2%) were euthanised due to behavioural reasons (Wilsson and Sundgren, 1997). The apparent minimal success of these breeding programs raises the ethical implications of breeding such a large quantity of dogs, further contributing to the domestic dog overpopulation.

When evaluating breed differences it is important to remember a dog’s early experiences may be just as influential on their behaviour as their innate tendencies (Rooney and Bradshaw, 2004). The extent to which the innate characteristics of a breed contribute to adult dog behaviour is largely unresolved and should be further investigated (Serpell and Jagoe, 1995; Willis, 1995; Appleby et al., 2002).

4.3 Influence of sex and neutering Whilst there are commonly seen variations within breeds, there is also variation between the sexes.

Females are typically easier to control, due to their smaller sizes, and have less aggressive tendencies

(Rebmann et al., 2000). This is important if the dog is to live in a home or kennel environment where contact with other dogs is inevitable (Rebmann et al., 2000; Rooney and Bradshaw, 2004). Whilst there are many considerations when choosing which sex of dog to use, it is important to note that individuals may not possess traits typical of their sex. Regardless of sex, it could be argued if breeding is not intended dogs should be de-sexed (Moore et al., 2001). Neutering has also been reported to increase a dog’s trainability in certain breeds (Serpell and Hsu, 2005). The benefits of neutering, however, are widely debateable, especially in regard to health benefits (Beauvais et al., 2012).

During a study (Maejima et al., 2007) male, neutered Labrador Retrievers had higher scores for

‘desire to work’, when compared to females and non-neutered males. Neutered dogs had significantly lower distractibility scores than non-neutered dogs (Maejima et al., 2007). Neutering therefore

12 reduced the dog’s distractibility (Maejima et al., 2007). Previous studies reported male Labrador

Retrievers scored higher than females for defence drive and hardiness, whilst females scored higher for ability to cooperate and lower level of aggression towards other dogs (Wilsson and Sundgren,

1997). Male German Shepherds and Labrador Retrievers also scored significantly higher than females for defence- and prey-drive, and courage (Wilsson and Sundgren, 1997). Male German Shepherds also scored significantly higher for cooperation, whilst the opposite was found for Labradors with females scoring significantly higher (Wilsson and Sundgren, 1997). Whilst their traits and abilities are varied, entire male dogs are still more commonly used for detection work than females and neutered male dogs (Wilsson and Sundgren, 1997; Maejima et al., 2007). This may be due to personal preference or bias during the dog selection process.

5.0 Is breed specific selection enough?

Historically it was widely agreed that animals of a certain age, species and sex would behave similarly

(Feaver et al., 1986). There is now substantial evidence suggesting a large variation amongst individuals’ behaviours within species and breeds (Manteca and Deag, 1993; Wielebnowski, 1999;

Buffington, 2002; Serpell and Hsu, 2005; King et al., 2012).

Temperamental factors are the primary determinant of a dog’s working ability (Maejima et al., 2007;

King et al., 2012; McGarrity et al., 2016) making certain individuals more suited to tasks than others

(Serpell and Hsu, 2001; Svartberg, 2002). Different breed lines (e.g. working lines vs show lines) are also likely to result in different behavioural attributes (Houpt and Willis, 2001; Serpell and Hsu,

2005). While the link between dog health and physical characteristics has been established (van Rooy et al., 2014), a similar link with behaviour has been discovered for a relatively narrow range of physical characteristics (Gácsi et al., 2009). For example, brachycephalic dogs are more successful in following human pointing signals than dolichocephalic dogs (Gácsi et al., 2009). A dog, however, should not be selected for detection work based solely on their breed (Rooney and Bradshaw, 2004;

McGarrity et al., 2016).

A dog’s environment and lifetime experiences are highly influential and cannot be overlooked when investigating a dog’s working suitability (van Rooy et al., 2014; McGarrity et al., 2016). All behaviours must be viewed with environmental context in mind, which may shine light on the behavioural response (van Rooy et al., 2014). Learning plays an important role in behavioural development, with dogs repeating previously successful behaviours (van Rooy et al., 2014). Early experiences therefore shape a dog’s development and future behavioural tendencies (van Rooy et al.,

2014).

Whilst selecting the best dog breed may increase the likelihood of an individual’s success at detection work, it will not guarantee it. Individual variation within breeds is typically immeasurable. What is clear is that each individual should be thoroughly tested and evaluated prior to selection, no matter the breed.

6.0 The importance of the dog handler

A dog and its handler together are a partnership, which strongly influences their work. A strong bond is typically formed, which is of great importance when working in the field (Rebmann et al., 2000;

Abney, 2009). Personality conflicts will severely compromise the dog and handler team’s working ability and success (Smith et al., 2003). A dog handler must be able to trust their dog’s indications (a trained behaviour which demonstrates a target sample has been located) and similarly the dog must have trust in their handler’s commands. A dog which has been injured or overworked through following their handler’s commands will unlikely work well for them. A dog handler’s experience will also influence the success of the team (Gutzwiller, 1990).

As with dogs, not everyone is a suitable dog handler (Rebmann et al., 2000). Whilst there are many characteristics that make up a suitable detection dog handler, some of the most important include: high level of fitness; knowledge of dog training and handling principles; trust in their dog’s behaviours; and ability to understand dog behaviour and body language (Rebmann et al., 2000). A successful dog and handler team is therefore created from the proper selection of both a handler and

14 their dog, and assessment of their compatibility; adequate training of both parties; and continual performance evaluation (Hurt and Smith 2009).

7.0 Conclusion and Recommendations

From the literature reviewed, a suitable detection dog is an individual of medium size, with a high level of agility; highly play motivated; and high level of intelligence and obedience, yet independence when working off-leash. Whilst certain breeds commonly possess the proposed ideal traits (i.e.

Herding and gun dogs), this does not mean that every individual will be suited to this work. Nor does it mean that no other breeds will have suitable individuals. In the future the focus should therefore not be the mass breeding of specific breeds deemed best suited, but instead locating specific individuals that have the characteristics required to be successful detection dogs.

Funding: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

References

Abney, D., 2009. Canine Tracking Guide: Training the all-purpose tracker. i-5 Publishing, Irvine.

Adamkiewicz, E., Jezierski, T., Walczak, M., Górecka-Bruzda, A., Sobczyńska, M., Prokopczyk, M.,

Ensminger, J., 2013. Traits of drug and explosives detection in dogs of two breeds as evaluated by their handlers and trainers. Anim. Sci. Pap. Rep. 31, 205-217.

Adams, V.J., Evans, K.M., Sampson, J., Wood, J.L.N., 2010. Methods and mortality results of a health survey of purebred dogs in the UK. J. Small. Anim. Pract. 51, 512-524.

Alpak, H., Mutuş, R., Onar, V., 2004. Correlation analysis of the skull and long bone measurements of the dog. Annals. Anat. 186, 323-330.

Appleby, D.L., Bradshaw, J.W.S., Casey, R.A., 2002. Relationship between aggressive and avoidance behaviour by dogs and their experience in the first six months of life. Vet. Rec. 150, 434-438.

Bartels, A., Martin, V., Bidoli, E., Steigmeier-Raith, S., Brühschwein, A., Reese, S., Köstlin, R.,

Erhard, M., 2015. Brachycephalic problems of pugs relevant to animal welfare. Anim. Welf. 24, 327-

333.

Beauvais, W., Cardwell, J.M., Brodbelt, D.C., 2012. The effect of neutering on the risk of mammary tumours in dogs – a systematic review. J. Small. Anim. Pract. 53, 314-322.

Beebe, S.C., Howell, T.J., Bennett, P.C., 2016. Using scent detection dogs in conservation settings: A review of scientific literature regarding their selection. Frontiers. Vet. Sci. 3, 1-13.

Bradshaw, J.W., Goodwin, D., Lea, A.M., Whitehead, S.L., 1996. A survey of the behavioural characteristics of pure-bred dogs in the United Kingdom. Vet. Rec. 138, 465-468.

Brownell, D.A., Marsolais, M., 2002. The Brownell-Marsolais Scale: A proposal for the qualitative evaluation of SAR/disaster K9 Candidates. Adv. Rescue. Technol. 5, 57-67.

Buffington, C.A.T., 2002. External and internal influences on disease risk in cats. J. Am. Vet. Med.

Assoc. 220, 994-1002.

Cablk, M.E., Heaton, J.S., 2006. Accuracy and reliability of dogs in surveying for Desert Tortoise

(Gopherus agassizii). Ecol. Appl. 16, 1926-1935.

Chesney, C.J., 1997. The microclimate of the canine coat: the effects of heating on coat and skin temperature and relative humidity. Vet. Dermatol. 8, 183-190.

Clarke, T., Cooper, J., Mills, D., 2013. Acculturation: perceptions of breed differences in the behaviour of the dog (Canis familiaris). Hum. Anim. Interact. Bull. 1, 16-33.

Coppinger, R., Coppinger, L., 2001. Dogs: A startling new understanding of canine origins, behaviour and evolution. Scribner, New York.

Coppinger, R., Schneider, R., 1995. Evolution of working dogs, in: Serpell, J. (Ed.), The domestic dog: its evolution, behaviour and interactions with people. Cambridge University Press, Cambridge, pp. 21-47.

Coren, S., 1994. The Intelligence of Dogs: How intelligent is your dog. Headline Book Publishing,

London.

Craven, B.A., Neuberger, T., Paterson, E.G., Webb, A.G., Josephson, E.M., Morrison, E.E., Settles,

G.S., 2007. Reconstruction and morphometric analysis of the nasal airway of the dog (Canis familiaris) and implications regarding olfactory airflow. Anat. Rec. Adv. Integr. Anat. Evolut. Biol.

290, 1325-1340.

Craven, B.A., Paterson, E.G., Settles, G.S., 2010. The fluid dynamics of canine olfaction: unique nasal airflow patterns as an explanation of macrosmia. J. R. Soc. Interface. 7, 933-943.

Duffy, D.L., Hsu, Y., Serpell, J.A., 2008. Breed differences in canine aggression. Appl. Anim. Behav.

Sci. 114, 441-460.

Duggan, J.M., Heske, E.J., Schooley, R.L., Hurt, A., Whitelaw, A., 2011. Comparing detection dog and livetrapping surveys for a cryptic rodent. J. Wildl. Manag. 75, 1209-1217.

Early, J.B., Arnott, E.R., Wade, C.M., McGreevy, P.D., 2014. Manual muster: a critical analysis of the use of common terms in Australian working dog manuals. J. Vet. Behav. Clin. Appl. Res. 9, 370-

374.

Fadel, F.R., Driscoll, P., Pilot, M., Wright, H., Zulch, H., Mills, D., 2016. Differences in Trait

Impulsivity Indicate Diversification of Dog Breeds into Working and Show Lines. Sci. Rep. 6, 1-10.

Feaver, J., Mendl, M., Bateson, P., 1986. A method for rating the individual distinctiveness of domestic cats. Anim. Behav. 34, 1016-1025.

Fels, L., Distl, O., 2014. Identification and validation of Quantitative Trait Loci (QTL) for Canine Hip

Dysplasia (CHD) in German Shepherd Dogs. PLoS. 9, e39620.

Fleming, J.M., Creevy, K.E., Promislow, D.E.L., 2011. Mortality in north American dogs from 1984 to 2004: an investigation into age-, size-, and breed-related causes of death. J. Vet. Intern. Med. 25,

187-198.

Frank, H., Frank, M.G., 1985. Comparative manipulation-test performance in ten-week-old wolves

(Canis lupus) and Alaskan Malamutes (Canis familiaris): a Piagetian interpretation. J. Comp.

Psychol. 99, 266-274.

Fratkin, J.L., Sinn, D.L., Patall, E.A., Gosling, S.D., 2013. Personality consistency in dogs: a meta- analysis. PLoS. 8, e54907.

Gácsi, M., McGreevy, P., Kara, E., Miklósi, Á., 2009. Effects of selection for cooperation and attention in dogs. Behav. Brain. Funct. 5, 31-38.

Gagnon, S., Doré, F.Y., 1992. Search Behavior in Various Breeds of Adult Dogs (Canis familiaris):

Object Permanence and Olfactory Cues. J. Comp. Psychol. 106, 58-68.

Galis, F., Van der Sluijs, I., Van Dooren, T.J.M., Metz, J.A.J., Nussbaumer, M., 2007. Do large dogs die young?. J. Exp. Zool. Mol. Dev. Evol. 308, 119-126.

Goddard, M.E., Beilharz, R.G., 1984. The relationship of fearfulness to, and the effects of, sex, age and experience on exploration and activity in dogs. Appl. Anim. Behav. Sci. 12, 267-278.

Graham, L.T., Gosling, S.D., 2009. Temperament and personality in working dogs, in: Helton, W.S.

(Ed.), Canine Ergonomics: The Science of Working Dogs. CRC Press, London, pp. 63-81.

Greer, K.A., Canterberry, S.C., Murphy, K.E., 2007. Statistical analysis regarding the effects of height and weight on life span of the domestic dog. Res. Vet. Sci. 82, 208-214.

Gutzwiller, K.J., 1990. Minimizing dog-induced biases in game bird research. Wildl. Soc. Bull. 18,

351-356.

Hall, N.J., Smith, D.W., Wynne, C.D.L., 2014. Effect of odor preexposure on acquisition of an odor discrimination in dogs. Learn. Behav. 42, 144-152.

Hart, B.L., Eckstein, R.A., 1997. The role of gonadal hormones in the occurrence of objectionable behaviours in dogs and cats. Appl. Anim. Behav. Sci. 52, 331-344.

Helton, W.S., 2009. Canine Ergonomics: The Science of Working Dogs. CRC Press, Boca Raton.

Helton, W.S., 2010. Does perceived trainability of dog (Canis lupus familiaris) breeds reflect differences in learning or differences in physical ability?. Behav. Process. 83, 315-323.

Houpt, K.A., Willis, M.B., 2001. Genetics of Behaviour, in: Ruvinsky, A., Sampson, J. (Eds.), The

Genetics of the Dog. CAB International, Wallingford, pp. 371-400.

Hurt, A., Smith, D.A., 2009. Conservation Dogs, in: Helton, W.S. (Ed.), Canine Ergonomics: The

Science of Working Dogs. CRC Press, London, pp. 175-194.

Jakovcevic, A., Elgier, A.M., Mustaca, A.E., Bentosela, M., 2010. Breed differences in dogs’ (Canis familiaris) gaze to the human face. Behave. Process. 84, 602-607.

Janutta, V., Hamann, H., Distl, O., 2006. Complex segregation analysis of canine hip dysplasia in

German Shepherd Dogs. J. Hered. 97, 13-20.

Jezierski, T., Adamkiewicz, E., Walczak, M., Sobczyńska, M., Górecka-Bruzda, A., Ensminger, J.,

Papet, E., 2014. Efficacy of drug detection by fully-trained police dogs varies by breed, training level, type of drug and search environment. Forens. Sci. Int. 237, 112-8.

Jones, A.C., Gosling, S.D., 2005. Temperament and personality in dogs (Canis familiaris): A review and evaluation of past research. Appl. Anim. Behav. Sci. 95, 1-53.

Kemp, T.J., Bachus, K.N., Nairn, J.A., Carrier, D.R., 2005. Functional trade-offs in the limb bones of dogs selected for running versus fighting. J. Exper. Biol. 208, 3475-3482.

King, T., Marston, L.C., Bennett, P.C., 2012. Breeding dogs for beauty and behaviour: why scientists need to do more to develop valid and reliable behaviour assessments for dogs kept as companions.

Appl. Anim. Behav. Sci. 137, 1-12.

Ley, J.M., Bennett, P.C., Coleman, G.J., 2009. A refinement and validation of the Monash Canine

Personality Questionnaire (MCPQ). Appl. Anim. Behav. Sci. 116, 220-227.

Lorenzo, N., Wan, T., Harper, R.J., Hsu, Y., Chow, M., Rose, S., Furton, K.G., 2003. Laboratory and field experiments used to identify Canis lupus familiaris active odor signature chemicals from drugs, explosives, and humans. Anal. Bioanal. Chem. 376, 1212-1224.

Maejima, M., Inoue-Murayama, M., Tonosaki, K., Matsuura, N., Kato, S., Saito, Y., Weiss, A.,

Murayama, Y., Ito, S., 2007. Traits and genotypes may predict the successful training of drug detection dogs. Appl. Anim. Behav. Sci. 107, 287-298.

Manteca, X., Deag, J.M., 1993. Individual Differences in Temperament of Domestic Animals: A

Review of Methodology. Anim. Welf. 2, 247-268.

Marshall-Pescini, S., Passalacqua, C., Barnard, S., Valsecchi, P., Prato-Previde, E., 2009. Agility and search and rescue training differently affects pet dogs’ behaviour in socio-cognitive tasks. Behav.

Process. 81, 416-422.

McGarrity, M.E., Sinn, D.L., Thomas, S.G., Marti, C.N., Gosling, S.D., 2016. Comparing the predictive validity of behavioural codings and behavioural ratings in a working-dog breeding program. Appl. Anim. Behav. Sci. 179, 82-94.

Mehrkam, L.R., Wynne, C.D.L., 2014. Behavioral differences among breeds of domestic dogs (Canis lupus familiaris): current status of the science. Appl. Anim. Behav. Sci. 155, 12-27.

Mehus-Roe, K., 2009. The Original Dog Bible: The Definitive Source for All Things Dog, 2nd ed.

BowTie Inc, New York.

Minhinnick, S., Papet, L.E., Stephenson, C.M., Stephenson, M.R., 2016. Training fundamentals and the selection of dogs and personnel for detection work, in: Ensminger, J., Jezierski, T., Papet, L.E.,

(Eds.), Canine Olfaction Science and Law. CRC Press, London, pp. 155-171.

Mirkó, E., Kubinyi, E., Gácsi, M., Miklósi, Á., 2012. A preliminary analysis of an adjective-based dog personality questionnaire developed to measure some aspects of personality in the domestic dog

(Canis familiaris). Appl. Anim. Behav. Sci. 138, 88-98.

Moore, G.E., Burkman, K.D., Carter, M.N., Peterson, M.R., 2001. Causes of death or reasons for euthanasia in military working dogs: 927 cases (1993-1996). J. Am. Vet. Med. Assoc. 219, 209-214.

Murphy, J.A., 1995. Assessment of temperament of potential guide dogs. Anthrozoös. 13, 224-228.

Murphy, J.A., 1998. Describing categories of temperament in potential guide dogs for the blind. Appl.

Anim. Behav. Sci. 58, 163-178.

Ohl, F., Arndt, S.S., van der Staay, F.J., 2008. Pathological anxiety in animals. Vet. J. 175, 18-26.

Ostrander, E., Wayne, R.K., 2005. The canine genome. Genome. Res. 15, 1706-1716.

Packer, R.M.A., Hendricks, A., Burn, C.C., 2012. Do dog owners perceive the clinical signs related to conformational inherited disorders as ‘normal’ for the breed? A potential constraint to improving canine welfare. Anim. Welf. 21, 81-93.

Palika, L., 2007. The Howell book of dogs: the definitive reference to 300 breeds and varieties. Wiley

Publishing, New Jersey.

Pongrácz, P., Miklósi, Á., Vida, V., Csányi, V., 2005. The pet dogs ability for learning from a human demonstrator in a detour task is independent from the breed and age. Appl. Anim. Behav. Sci. 90,

309-323.

Prato-Previde, E., Marshall-Pescini, S., Valsecchi, P., 2008. Is your choice my choice? The owners’ effect on pet dogs’ (Canis lupus familiaris) performance in a food choice task. Anim. Cogn. 11, 167-

174.

Rauth-Widmann, B., 2006. Your dog’s senses – Understand how he perceives his world, 2nd ed.

Cadmos Equestrian, United Kingdom.

Rebmann, A., David, E., Sorg, M.H.H., 2000. Cadaver dog handbook: forensic training and tactics for the recovery of human remains. CRC Press, Boca Raton, Florida.

Reed, S.E., Bidlack, A.L., Hurt, A., Getz, W.M., 2011. Detection distance and environmental factors in conservation detection dog surveys. J. Wildl. Manag. 75, 243-251.

Rocznik, D., Sinn, D.L., Thomas, S., Gosling, S.D., 2015. Criterion analysis and content validity for standardized behavioural tests in a detector-dog breeding program. J. Forens. Sci. 60, 213-221.

Rooney, N.J., Bradshaw, J.W.S., 2004. Breed and sex differences in the behavioural attributes of specialist search dogs—a questionnaire survey of trainers and handlers. Appl. Anim. Behav. Sci. 86,

123-135.

Rooney, N.J., Gaines, S.A., Bradshaw, J.W.S., Penman, S., 2007. Validation of a method for assessing the ability of trainee specialist search dogs. Appl. Anim. Behav. Sci. 103, 90-104.

Ruefenacht, S., Gebhardt-Henrich, S., Miyake, T., Gaillard, C., 2002. A behaviour test on German

Shepherd dogs: heritability of seven different traits. Appl. Anim. Behav. Sci. 79, 113-132.

Saetre, P., Strandberg, E., Sundgren, P., Pettersson, U., Jazin, E., Bergström, T.F., 2006. The genetic contribution to canine personality. Genes. Brain. Behav. 5, 240-248.

Serpell, J.A., Duffy, D.L., 2014. Dog Breeds and Their Behaviour, in: Horowitz, A. (Ed.), Domestic

Dog Cognition and Behaviour. Springer Berlin Heidelberg, Berlin, pp. 31-58.

Serpell, J.A., Hsu, Y., 2005, ‘Effects of breed, sex, and neuter status on trainability in dogs. Anthrozoös. 18, 196-207.

Serpell, J.A., Jagoe, J.A., 1995. Early experience and the development of behaviour, in: Serpell, J.

(Ed.), The domestic dog: Its evolution, behaviour and interactions with people. Cambridge University

Press, United Kingdom, pp. 79-102.

Sinn, D.I., Gosling, S.D., Hillards, S., 2010. Personality and performance in military working dogs:

Reliability and predictive validity of behavioural tests. Appl. Anim. Behav. Sci. 127, 51-65.

Slabbert, J.M., Odendaal, J.S.J., 1999. Early prediction of adult police dog efficiency—a longitudinal study. Appl. Anim. Behav. Sci. 64, 269-288.

Smith, D.A., Ralls, K., Hurt, A., Adams, B., Parker, M., Davenport, B., Smith, M.C., Maldonado,

J.E., 2003. Detection and accuracy rates of dogs trained to find scats of San Joaquin kit foxes (Vulpes macrotis mutica). Anim. Conserv. 6, 339-346.

Svartberg, K., 2002. Shyness–boldness predicts performance in working dogs. Appl. Anim. Behav.

Sci. 79, 157-174.

Svartberg, K., 2005. A comparison of behaviour in test and in everyday life: evidence of three consistent boldness-related personality traits in dogs. Appl. Anim. Behav. Sci. 91, 103-128.

Svartberg, K., 2006. Breed-typical behaviour in dogs – historical remnants or recent constructs?.

Appl. Anim. Behav. Sci. 96, 293-313.

Svartberg, K., Forkman, B., 2002. Personality traits in the domestic dog (Canis familiaris). Appl.

Anim. Behav. Sci. 79, 133-155.

Turcsán, B., Kubinyi, E., Miklósi, Á., 2011. Trainability and boldness traits differ between dog breed clusters based on conventional breed categories and genetic relatedness. Appl. Anim. Behav. Sci. 132,

61-70. van Rooy, D., Arnott, E.R., Early, J.B., McGreevy, P., Wade, C.M., 2014. Holding back the genes: limitations of research into canine behavioural genetics. Canine. Genet. Epidemiol. 1, 7-17.

Vas, J., Topál, J., Gácsi, M., Miklósi, Á., Csányi, V., 2005. A friend or an enemy? Dogs’ reaction to an unfamiliar person showing behavioural cues of threat and friendliness at different times. Appl.

Anim. Behav. Sci. 94, 99-115.

Wielebnowski, N.C., 1999. Behavioral differences as predictors of breeding status in captive cheetahs. Zoo. Biol. 18, 335-349.

Willis, M.B. 1995. Genetic aspects of dog behaviour with particular reference to working ability, in:

Serpell, J. (Ed.), The domestic dog: Its evolution, behaviour and interactions with people. Cambridge

University Press, United Kingdom, pp. 51-64.

Wilsson, E., Sundgren, P., 1997. The use of a behaviour test for the selection of dogs for service and breeding, I: Method of testing and evaluating test results in the adult dog, demands on different kinds of service dogs, sex and breed differences. Appl. Anim. Behav. Sci. 53, 279-295.

Zhong, H., Levalle, R.R., Moghaddam, M., Nof, S.Y., 2015. Collaborative intelligence – definition and measured impacts on internetworked e-work. Manag. Prod. Eng. Rev. 6, 67-78.

Table 1. Dog types and their common behavioural attributes.

Dog Type Common attributes References Longevity (years) References Gun dogs  Low aggression Vas et al. 11 – 13 (Labrador Palika (2007); (e.g. Labrador levels (2005) Retrievers) Mehus-Roe Retrievers,  Cooperative with 12 – 15 (English (2009) English humans Springer Spaniels) Springer  Highly trainable Helton (2010); Spaniels) Turcsán et al. (2011)  Strong chase Palika (2007); instincts – Mehus-Roe potential threat to (2009) small animals  High stamina Herding dogs  Highly trainable Coren (1994); 13 – 15 (Border Palika (2007); (e.g. Border and intelligent Serpell and Collie) Mehus-Roe Collies, Hsu (2005); 12 – 14 (Australian (2009) Australian Helton (2010); Cattle Dog) Cattle Dogs, Turcsán et al. 9 – 11 (German German (2011) Shepherds) Shepherds)  Strong play-drive Svartberg and Forkman (2002)  Independent Serpell and problem solvers Hsu (2005);  Cooperative with Jakovcevic et humans al. (2010)  High stamina Svartberg  Bold (2002); Palika (2007); Mehus- Roe (2009) Terriers (e.g.  Poor trainability Helton (2010) 14 – 16 (Jack Palika (2007); Jack Russell  High energy levels Palika (2007); Russell Terriers) Mehus-Roe Terriers)  Strong play- and Mehus-Roe (2009) prey-drive (2009)  Prone to behavioural problems  Aggressive Duffy et al. tendencies (2008) Sight-hounds  Susceptible to Alpak et al. 12 – 14 Palika (2007); (e.g. injury (due to low (2004); Kemp (Greyhounds) Mehus-Roe Greyhounds) bone mass) et al. (2005); (2009)  Poor Helton (2007a) manoeuvrability  Poor trainability Helton (2010); Turcsán et al. (2011)  Single-minded Palika (2007);  Disobedient off- Mehus-Roe leash (2009)

Scent-hounds  Sociable yet Svartberg and 9 – 11 Palika (2007); (e.g. stubborn Forkman (Bloodhounds) Mehus-Roe Bloodhounds,  Moderate energy (2002) 14 – 15 (Beagles) (2009) Beagles) levels  Relatively poor Coren (1994); trainability Ley et al. (2009)  Single-minded Palika (2007);  Disobedient off- Mehus-Roe leash (2009)