Wednesday, 31 October 2012

Social Referencing in Dogs

When human infants see something they are unsure of, they look to their caregiver to see what their reaction is. This is called social referencing. It has two components: first of all, a look from the object to the caregiver; and second, a reaction to the object (approach or avoidance) that is influenced by the caregiver’s response. This is well established in infants at twelve months of age. Do dogs do the same thing?

Two recent papers by Merola and colleagues set out to investigate, using a method similar to infant studies. They needed a slightly-scary object; something that will make a dog feel cautious, but not so scary that it will turn and run away. They decided to use an electric fan with streamers attached. 

In the first paper, published in Animal Cognition, the owner brought their dog into the room with the fan. The fan was at the far end of the room, and as soon as the owner closed the door, the fan was turned on by remote control. The owner stopped at a specific mark on the floor and released the dog.  The owner then stood still and looked at the fan with a neutral expression (phase 1). What happened next depended on whether the dog was assigned to a positive or negative condition. There were three further phases in which the owner gave a positive or negative response to the fan using speech and facial expression (phase 2), and movement towards or away from the fan (phases 3 and 4). These reactions were later rated by people who were blind to the aims of the experiment, to confirm that they were indeed positive or negative as intended. The dog’s behaviour was observed throughout.

A pretty biewer yorkie with an autumnal display of fruits and foliage
Photo: Liliyana Kulianionak / Shutterstock

Seventy-five dogs took part. Seventeen were excluded from analysis because of mistakes by the owners, and some were excluded from most of the analyses because they confidently approached the fan right at the start. Of the remaining dogs, 83% looked at their owner at least once after seeing the fan. Once the owners started reacting to the fan, dogs in the negative group were significantly more likely to remain still than those in the positive group. Also, in the last two phases of the study (once the owner had moved), dogs in the negative condition spent significantly more time interacting with the owner. This shows they have responded to their owner’s negative message by avoiding the fan.

This study shows that most of the dogs engaged in social referencing to see what their owner thought of the fan. However, the experiment had an initial phase in which the owner was neutral, which is different from studies with infants. This disrupted normal social referencing behaviour, since the owner was artificially silent in response to the dog’s look, and only began to respond after a pre-set time had elapsed. Also, it would be interesting to know whether dogs do social referencing with a stranger as well as their owner.

The second paper, published in PloS One, involved a new set of ninety dogs. This time, both the owner and a stranger were in the room with the dog. Either the owner or stranger acted as the informant, while the other person sat on a chair and read a book throughout, paying no attention to the dog. The experimental procedure was similar, except this time the informant began responding to the fan as soon as the dog looked back at them (phase 1). Then, the fan was turned off (phase 2), and the informant stayed in the same place, but continued to give the positive or negative message every time the dog looked at them. This design is much closer to that used in the infant cognition literature. 

As before, some results had to be discarded either because of errors made by the owners or because the dogs were very confident about the fan. Results from the remaining dogs showed that 76% of dogs with the owner as informant, and 60% of dogs with the stranger, showed referential looking at the informant.  There were significant differences in behaviour depending on whether the message was positive or negative. Interestingly, there is also evidence that dogs responded more to their owner than to a stranger. When the informant was the owner, dogs in the positive group reached the space near the fan more quickly, and dogs in the negative group took longer to reach the fan, than when the informant was a stranger. When the message was negative, dogs looked to the seated person more if it was the owner rather than a stranger, suggesting that they wanted information from their owner too. 

At the end of both studies, the fan was turned off and the experimenter sat next to it and gave the dogs treats. This was to make sure the dogs would not be frightened by fans in future.

These two studies show that dogs use gaze to look at a person for information when they are faced with something they are unsure about, and their subsequent behaviour is based on the person’s reaction. With some small differences, these results are very similar to those found in studies of infants.

Have you ever noticed your dog looking to you for information about something unfamiliar?

References
Merola, I., Prato-Previde, E., & Marshall-Pescini, S. (2011). Social referencing in dog-owner dyads? Animal Cognition, 15 (2), 175-185 DOI: 10.1007/s10071-011-0443-0
Merola, I., Prato-Previde, E., & Marshall-Pescini, S. (2012). Dogs' Social Referencing towards Owners and Strangers PLoS ONE, 7 (10) DOI: 10.1371/journal.pone.0047653

Wednesday, 24 October 2012

Homeless Pets: A UK Survey


The problem of pet overpopulation and homelessness is well known. Getting accurate figures for the number of homeless pets is a more difficult undertaking, since many organizations are responsible for stray and homeless animals. The results of a survey in the UK were recently published, and provide useful information about the scale of the problem, the wait times for animals to be accepted into rescue, and the likely outcome of their stay.

The survey was conducted by Jenny Stavisky and colleagues at the University of Nottingham. They sent a questionnaire to all the rescue organizations they could identify in the UK. They used a snowballing technique, asking each organization to suggest other groups that they should contact. They identified over 2300 contacts, and got an excellent response rate of close to 40%. In some cases, the head office of an organization provided some information, while other details came from the branches.

A lonely pomeranian lies down on the street
Photo: Sergey Skleznev / Shutterstock

The results show that during 2010, the organizations in the survey cared for 156,826 cats and 89,571 dogs. (Remember the real number of homeless animals in the UK will be much greater, since some organizations did not participate). About half of the animals were handed in by their owners, while others came in as strays or were seized because of animal welfare problems. 

The good news is that 77% of the cats and 75% of the dogs were rehomed. Sadly, though, the second most common outcome was euthanasia: 13% of cats and 10% of dogs were euthanized. In other words, 13,000 cats and 9,000 dogs were put to sleep. Although some may have been euthanized because of serious health or behavioural issues, it is inevitable that healthy, adoptable animals were euthanized too.

Another major problem was waiting lists, with 62% reporting a waiting list for cats and 44% reporting a waiting list for dogs. On average, the waiting list for dogs was equivalent to a third of the capacity of the shelters, and for cats it was even greater at half the shelter capacity. The worst case was an organization that had a waiting list of more than 16 times the number of dogs they could accommodate.

The survey also found that these organizations depend heavily on volunteers. Although over 19,000 people were involved in the animals’ care, over 76% of them were part-time volunteers.  The costs are also high; in total, the organizations spent close to 330,000 pounds in the 2009-2010 financial year.

It is difficult to calculate the total number of un-owned dogs and cats in the UK from this survey. The main animal welfare organizations all took part, and most of the organizations that did not respond were small, but it is hard to generalize from these figures. Organizations also differ in terms of euthanasia policies. 

For anyone in the unfortunate position of needing to rehome a dog, one piece of advice we can take from this study is to go through a breed-specific rescue if possible, as these tended to have shorter waiting lists than places that take in dogs of all breeds/cross-breeds.

The study concludes that there is a sizeable population of un-owned cats and dogs in the UK. They say that “despite substantial quantities of manpower and money expended on these animals, it appears that at this time there is still a continual flow of animals out of ownership and into the guardianship of rescues and shelters.” 

The survey was conducted at a time of recession in the UK, which may have increased animal relinquishment, although a study in Chicago found only a slight difference. The problem is multifactorial, and it is likely that better education of pet owners, spay and neuter programs, campaigns for better provision of pet-friendly housing, and greater support for animal adoption would all help. You can read the results of a recent AHA survey on barriers to animal adoption here.
 
What do you think should be done to reduce the number of un-owned cats and dogs?

Reference
Stavisky, J., Brennan, M., Downes, M., & Dean, R. (2012). Demographics and economic burden of un-owned cats and dogs in the UK: results of a 2010 census BMC Veterinary Research, 8 (1) DOI: 10.1186/1746-6148-8-163

Wednesday, 17 October 2012

Behavioural problems in rabbits, rodents and ferrets

Many people keep rabbits, rodents and ferrets as pets. A study published last year by Normando and Galli (Padua University) is the first to investigate the kind of behavioural problems they have and how it affects owners’ feelings of satisfaction with their animals.

Participants were recruited via an Italian rabbit forum, the University of Padua, and local veterinary clinics. The survey was completed by 193 people about a total of 371 pets. The pets included 184 rabbits, 59 mustelids (mainly ferrets, but also including two skunks), and 128 rodents (including guinea pigs, hamsters, gerbils, chinchillas, rats and other rodents). 

Three different rabbits eating from a bowl
Photo: Oksana Shufrych / Shutterstock

Most owners reported no problems, but 29% of rabbit owners, 53% of mustelid owners, and 20% of rodents had a behavioural problem. For rabbits, the most common problems were inappropriate toileting, destructiveness, and not being cuddly enough. The most common problem with ferrets was being aggressive, followed by house-soiling and disobedience. For rodents, the main problem reported was not being sociable or cuddly enough.  

The questionnaire also asked about repetitive stereotypies, behaviours like chewing on the cage bars or pacing. Owner reports on this are hard to assess, since some behaviours might be alright up to a certain level, and only be problematic if they occur too frequently; the authors had to exclude a small number of reports. The analysis showed a link between the prevalence of stereotypies and the animal’s housing; pets with less freedom to roam were more likely to be reported as displaying a stereotypy.

In addition to the questionnaire, a subset of the animals were brought by their owners to the lab, to see how they behaved during a mock-up of the early stages of a visit to the vet. For the two skunks, the procedure had to be halted because the animal was aggressive, but most of the other animals performed well.

A curious ferret walking across a piano keyboard
Photo: grynold / Shutterstock
It’s interesting that even when the animals had behavioural problems, it did not mean that owners felt dissatisfied with their pet. This suggests the behaviour problems were not severe and did not interfere with the relationship. The owner had been bitten at least once by 96 of the animals, but this did not usually mean that the owner considered the animal to be aggressive. Aggression towards strangers was found significantly more often amongst the mustelids than the rabbits and rodents. 

Although owners had more complaints about mustelids, they also found them more satisfying as pets. This is perhaps because they are inquisitive and social animals, and so the owners find it more interesting to interact with them. However, it is also possible that people with many complaints would have rehomed their pet, and hence were not in the survey.  

The finding about stereotypies is consistent with what is known about laboratory animals, and shows the importance of an enriched and appropriate environment for the pet. 

Do you have a rabbit, ferret or rodent as a pet? If so, what do you like about it?

Reference
Normando, S., & Gelli, D. (2011). Behavioral complaints and owners' satisfaction in rabbits, mustelids and rodents kept as pets Journal of Veterinary Behavior,, 6 (6), 337-342 DOI: 10.1016/j.jveb.2011.01.005

Wednesday, 10 October 2012

CAWC report on shock collars

In September, the UK’s Companion Animal Welfare Council published a report on the scientific evidence on the use of shock collars in dog training. They use the term ‘electronic pulse training aids’ or EPTAs, because the collars do not necessarily induce a ‘shock’ but may sometimes be used only to induce a tickling sensation. I will use the everyday term here. The report included the use of collars as a training aid as well as invisible fences designed to administer an electric current if the dog crosses a boundary.

The independent review was chaired by Professor D.S. Mills, and looked at the scientific evidence, accepted submissions from interested parties, and undertook a small-scale survey of their use in the UK. The ten peer-reviewed studies discussed in the report looked at the use of shock collars for a surprisingly wide range of behaviours, including chasing, barking, and preventing acral lick dermatitis (‘hot spots’). The report discusses many problems with the literature. For example, one study which found the shock collar to be effective in preventing hot spots only included 5 dogs; a further 5 had to be excluded because the owners – although willing to use the collar – were unwilling to use it in the way required for the study. The report is to be commended for the thorough way in which these studies are discussed.

Boxer puppy wearing shock collar
The report says there is an "unnecessary risk to animal welfare in the unregulated availability of the current range of devices"
Photo: Charlene Bayerle / Shutterstock

The question is also a moral and ethical one. The report received submissions from both sides of the debate, and says each side believes it has animal welfare at heart. The typical argument of those in favour of their use is perhaps that of stopping chasing and therefore preventing a dog from being shot for harrying sheep. However, the report points out that in this case, a lead could be used instead. Each argument for-or-against the use of shock collars is considered.

An internet survey of the use of shock collars collected responses from 188 people. 8% were using EPTAs on cats, mainly to prevent straying. The remainder were used on dogs, mainly for obedience but invisible fences were also used. The report estimates that there are 350,000 EPTAs in the UK.

The report concludes that there is not enough scientific evidence to say whether shock collars are effective or not, but there is evidence that if mis-used they can cause harm. They suggest that if the UK Parliament decides to continue to allow their use, a number of safeguards should be implemented, including a requirement for users to be licensed, a warning signal (conditional stimulus) to be made prior to the electric shock, the ability to cancel the shock if the warning signal elicits the required behaviour, and some kind of visible or other warning for invisible fences. They also say that if a dog is barking out of distress, use of an anti-barking collar would be inappropriate, since it will not resolve the dog’s distress.

One study that I was surprised was omitted is that of Meghan Herron et al. Herron’s study of dogs that had been referred for behavioural problems found that 7% were reported to have an aggressive response to use of the shock collar. In fact, the CAWC report does not clearly explain how studies were identified and chosen for inclusion. Presumably Herron’s paper wasn’t considered because the working group excluded survey designs; this is surprising since they included case studies and conducted their own brief survey. The CAWC report already acknowledges that shock collars have the potential to cause harm, so the inclusion of Herron’s study may not have changed their findings. However, Herron's study does suggest a potential risk to the owner, as well as to the dog.

The wider evidence on positive vs negative reinforcement in dog training was not considered, because it was beyond the group's remit. Many surveys have found that owners who use positive reinforcement only have better behaved dogs. If you’d like to know more about these studies, I wrote a series here.

The report alludes to future studies that will directly compare shock collars to other methods, and says its findings must be considered in the light of this research as it becomes available. Shock collars are already banned in Wales; it remains to be seen what UK Parliament will decide.

The full report is 92 pages and you can read it here.

Are shock collars and invisible fences legal where you live?

Reference:
Companion Animal Welfare Council (2012) The use of electronic pulse training aids (EPTAs) in companion animals. Available online at cawc.org.uk.

Wednesday, 3 October 2012

Canine Neuroscience

The main problem with the neuroscience of dogs is that they would have to be sedated to be in the scanner, and then their brain wouldn’t be doing its normal stuff. Until now.

A team of scientists led by Gregory Berns at Emory University has successfully trained two dogs to go into the fMRI scanner and keep still long enough for a brain scan. Prof Berns says he got the idea from realizing what military dogs are trained to do – if a dog can parachute out of a plane with its handler, he thought, then surely it could do an fMRI.

The dogs are Callie, a two-year-old feist (small hunting dog), and McKenzie, a three-year-old border collie. And while McKenzie does agility, Callie had only had basic obedience training, and is a rescue dog. (If anyone ever tries to say negative things about rescue dogs, tell them about Callie!).

Dogs can haz brainscanz?

The dog training was complex and took place over several months. A mock-up of the scanner was made for each dog, including a replica head coil, a tube of the same size as the real thing, and a patient table within the tube with a head rest for the dog. Because dogs’ hearing is so sensitive, they also had to learn to wear headphones to protect their ears. The first times the scientists actually started the scan, the sound caused a startle reaction, so they played the sound throughout the training sessions to get the dog used to the noise that the machine makes.

The dogs were trained using positive reinforcement, and had to lie still with their head in a chin rest. Once the dog was used to this, the chin rest was moulded to give a custom fit, because it’s important for the dog’s head not to move in order to allow the scan to be interpreted. Finally, they were ready for the real thing.

What task was used for this ground-breaking experiment? The researchers wanted to know if there is a different pattern of activity in the brain when the dog sees a hand-signal that means their owner is about to give them a treat, compared to when they see a hand-signal that means no treat. The hand signals were left hand held up to mean the dog was about to receive a piece of hot dog, and both hands pointing horizontally to each other to mean no hot dog was forthcoming.

The dogs were trained on this task for ten minutes a day for several weeks prior to the actual experiment. The dog had to hold still for ten seconds while the hand signal was made, and then if it was the ‘treat’ signal the owner reached into the scanner to deliver some hot dog; the dog could move to get the treat and then had to go back into position.

Seven border collies posing for a group photo
Do you think these border collies are anticipating a reward?
Photo: Ksenia Rayknova / Shutterstock

Previous work on people and monkeys has shown that the caudate region of the brain is activated in expectation of a reward. The scientists found activation in the ventral caudate region of the dogs’ brains in response to the hand signal that denoted a treat, but not for the other hand signal; this shows the dog had learned to expect a reward.

This study is exciting because it demonstrates that canine neuroscience is possible. A future study might look for any differences in activation depending on whether it is the owner or someone else who makes the hand signal. This would tap into the same wider debate as that considered by Feuerbacher and Wynne in their investigation of whether dogs and wolves prefer treats or social interaction as a reward. 

The experiment was conducted with great care for the dogs’ wellbeing and they were free to exit the scanner at any time. The researchers make some useful comments about the ethics of this kind of study; for example, they say it wouldn’t be appropriate to use laboratory-bred dogs as they would have no choice whether to take part in the experiment. 

Emory University made a short video about the research which you can see here.

If you could train your dog to go in an MRI scanner, what would you test?

Reference:
Berns GS, Brooks AM, & Spivak M (2012). Functional MRI in awake unrestrained dogs. PloS one, 7 (5) PMID: 22606363
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