While desexing bitches is a common surgery, I was pleased to see Kim et al. take note that “the side effects of the operation, particularly any changes in behaviour, have been quantified in only few studies”.
That is to say, despite us commissioning vets to take the ovaries and uterus out of a great many bitches, we don’t really have much research about it. It’s a pretty scary state of play.
This particular study took 14 healthy German Shepherd bitches, between 5 and 10 months old. Half of these dogs were spayed, and the other half left entire. (The bitches were assigned to each group randomly, except for litter sisters, which were assigned opposite groups.)
After the spay, and having been given 4-5 months to recover from the surgery, the bitches were filmed in their kennel as a stranger and a dog approached. This footage was then scored based on how reactive the bitch was. A score of ’3′ indicated severe reactivity, and a score of ’0′ indicated no reactivity. The scorer was unaware of whether the bitch was spayed or not.
Photo courtesy of Rachel Willis.
The reactivity of each bitch was recorded several times, and the reactivity of each bitch declined over the study. It’s likely that the bitches habituated to the novel stimuli. However, despite this affect, bitches in the ovary-hysterectomy group scored higher throughout the study.
Before generalising these results, there are some matters to consider:
Reactivity was only measured in a kennel setting, and how these dogs react in the ‘real world’ may be different. We can’t suppose that our pet dogs are going to respond in the same way as kennel dogs.
The reactivity of these dogs was not measured at the start of the study. While it is unlikely, perhaps more reactive dogs happened to fall into the treatment group by chance. Without a ‘before desexing’ score, we cannot be sure of this.
The authors make note that these results are for German Shepherd bitches aged 5-10 months old. We can’t assume dogs of all breeds and ages would respond this way to spays.
Further, the bitches in this study are working lined German Shepherds, which may be more reactive than the typical pet dog.
However, this study notes that other studies on bitch spays have shown that as a group spayed bitches are:
More likely to gain weight
More aggressive than prior to spay (if they were aggressive prior to spay)
More likely to have urinary incontinence
More likely to be reactive after surgery
The authors recommend:
[V]eterinary practitioners should inform owners that a bitch may become more reactive after spaying either because they have lost the calming effects of progesterone or because elevated gonadotropins stimulate release of adrenal androgens.
Source: Kim HH, Yeon SC, Houpt KA, Lee HC, Chang HH, & Lee HJ (2006). Effects of ovariohysterectomy on reactivity in German Shepherd dogs. Veterinary journal (London, England : 1997), 172 (1), 154-9 PMID: 16772140
Entire (undesexed) dogs are 2.6 times more likely to bite than those that are spayed or neutered (desexed)
Are undesexed dogs really that risky?
I decided to read the three studies referenced individually.
Messam, LL, Kass, PH, Chomel, BB, Hart, LA 2008, ‘The human-canine environment: a risk factor for non-play bites?’, Veterinary Journal, 177(2); 205-15.
This study used data from 2003 (11 years ago) collected in Kingston, Jamaica and San Fransico, USA. Participants were recruited from vet clinic waiting rooms where they were presented with a questionnaire, set to determine the nature of their dog’s biting behaviour (and differentiating it from play biting).
When it came to comparing entire and gonadectomised dogs, this research suggests:
Intact dogs are more likely to bite than desexed dogs
Intact males are 1.68 times more likely to bite than desexed males
Intact males were 0.8 times more likely to bite than intact females
Spayed females were the ‘least bitey’
Guy, NC, Luescher, UA, Dohoo, Se, Spangler, E, Miller, JB, Dohoo, IR and Bate, LA 2001, ‘Demographic and aggressive characteristics of dogs in general veterinary caseload’, Applied Animal Behaviour Science, vol 74, iss 1.
This research is based on data collected in Cannada in 1996 (18 years ago), targeting owners with a questionnaire waiting for vet appointments in three Canadian provinces. Their results indicate:
The lowest level of aggression (biting and growling) was reported in intact female dogs
Intact male dogs were twice as likely to have bitten as intact female dogs
Intact male dogs and neutered females incidents of biting was reported at a similar level
And to quote:
“Relative to intact female dogs, neutered male dogs of at least 1 year of age were at the highest risk for having previously shown biting behaviour, followed by neutered female dogs, and intact males… [O]ur results indicate that the behavioural outcomes of [neutering] are worthy of further investigation.”
Gershman, KA, Sacks, JJ & Wright, JC 1994, ‘Which dogs bite? A case-control study of risk factors’, Pediatrics, 93 (6 pt 1), 913-7.
This study used data from 1991 (23 years ago) using 178 dog bites requiring medical treatment of a non-household-member in Denver, USA. Data was only used for dogs that had not bitten before. The study itself recognises this is a small sample size.
Their data concludes:
not-neutered dogs were 2.6 times more likely to bite
chained dogs were 2.8 times more likely to bite
dogs living with a baby were 3.5 times more likely to bite
male dogs were 6.2 times more likely to bite
So, are entire dogs 2.6 times more likely to bite?
If you are looking at the study in Denver, USA, in 1991 (23 years ago!) then, yes, their conclusions indicate that intact dogs are 2.6 times more likely to bite than desexed dogs.
But the other evidence referenced by the AVA does not make the exact same conclusions. The study conducted in 2003, using data from Jamaica and the USA, found that intact males were 1.68 times more likely to bite than castrated males, and 0.8 times as likely to bite as intact females. (This study is also old, with the data being collected 11 years ago.)
And that other article, with data from Canada in 1996 (18 years ago) makes pretty much the opposite conclusion. They found that neutered male dogs were the riskiest in terms of bites.
Questions to ask…
Why are we relying on data over a decade (or two decades) old? If aggression in entire dogs was a common phenomenon, surely we would have countless studies showing this problem.
The panel questioned why anyone would have a pit bull when they’re ‘not pets’, and ‘they’re fighting dogs’, with a history of ‘bad accidents’. They criticised public response to this incident saying, “I don’t understand how they’re blaming the babysitter instead of the owner of the dog”.
Paula Abdul is the only one who says anything mildly positive, with “not every part of that breed is bad”.
Understandably, dog lovers were pretty unimpressed with this coverage and criticised Studio 10 through social media.
And Studio 10 then had a ‘right of reply’ panel. And here is how it went down.
While the guise of this discussion was providing balance, Studio 10 clearly pulled the shots, asked the questions, and didn’t provide adequate right-of-reply in many instances. Here’s a blow by blow of what was said… And what I would’ve said.
The little starting introductory video/graphic describes some dog breeds being ‘banned in Australia’, and then describes that in 2011 half of dog attacks were by five breeds (Bull Terriers, Australian Cattle Dogs, American Staffordshire Terriers, German Shepherd Dogs, and Rottweilers). It then goes on to make the claim that bites by restricted breeds are decreasing.
There’s a lot of stuff in this that the expert panel did not get a chance to address!
Firstly, no breed is banned in Australia. The five breeds listed are ‘restricted breeds’, meaning that the way they are owned is regulated by most states, but no state outwardly bans them.
While we can dispute the validity of the statistics on breed attacks, it should be pointed out that the pit bull terrier does not appear in the list of breeds involved in half of all dog attacks.
While bites by restricted breeds may be decreasing (and I’m not even sure if that is true), that doesn’t mean bites overall are decreasing.
Studio 10 asks, “Why do you think pit bulls have such a bad public perception?”
Dr Andrew O’Shea, from the Australasian Veterinary Association, answers this: Because the media chooses to report on pit bull attacks almost exclusively. The media sensationalistness has a lot to answer for. As Dr O’Shea points out, many reports are ‘it’s a pit bull terrier’, when it’s not really. Dr O’Shea points out that the media makes them out to be ‘more dangerous’, but in reality they’re probably just as dangerous as any dog of a similar size. Any dog with teeth can bite.
“But Dr O’Shea, I’m confused though, because the media is reporting we’re told, say by the police and other people at the scene, and I think, there is, like you say, there’s a bit of confusion about talking about pit bulls, er, are the crossed with staffordshire terriers, I mean, I must say, sitting here in the studio, I’m very nervous, I’m, I mean, because of the dogs. I feel frightened.”
Not really a question, nor articulately asked, but then you didn’t give the panel a chance to reply either.
What is significant is not just that the media is reporting on ‘pit bull’ attacks, but the fact that attacks by breeds that are not pit bulls are not reported on. For example, in Port Lincoln an 8 year old boys had his nose bitten off by an Australian bulldog. This barely made the news, and when it did, the report focussed on the death of Ayen Chol by a pit bull. While the news heavily reported on Isabelle Dinoire who received the first face transplant, but neglected to report that her facial injuries were as a result of a labrador mauling.
The fact that you feel frightened is probably a consequence of the media hysteria surrounding pit bulls. I am sorry that you’re fearful, but your fear is illegitimate, and proves that we need to reassess the way dog attacks are perpetuated in the media. When two dogs lay in a relaxed and quiet way in a studio (a totally foreign environment to them), and they are regarded as scary, then the community clearly needs a much more comprehensive understanding of dogs and dog behaviour.
“Centuries ago, they were bred as fighting dogs. Am I right in saying that?”
Dr O’Shea responds to this by basically agreeing, but argues that defining ‘pit bulls’ is complex, and many dogs that look like a pit bull are classified as one despite not being one. And despite being crossbreed. He says that because they’re a bigger breed and tend to be reactive, they seem to get a bad name.
However, I would’ve taken a different response in responding here… I would’ve said:
Yes, but many dogs have roles now vastly different to their original purpose. Many Labradors are bred to assist blind people – while their original purpose was to carry dead birds around. Many German Shepherds are bred for multi-purpose police roles, including biting people, while their original purpose was herding sheep. Many people own terrier breeds who were bred to kill small vermin. Overtime, breed roles change. Additionally, within a breed, there are many variations in terms of personality and type. If you look at the greyhound industry, you’ll see a vast number of greys are killed for not meeting the task at hand, despite breeding specifically for running fast after quarry. You can imagine, in our current era, where dogs are primarily bred as pets, the history of a dog does not have a large implication on the temperament of the dogs we see today.
“A big reactive dog sounds quite scary to me, though. I mean, why, why, what I don’t understand is why people are so passionate about pit bulls in particular. Like, why, I mean, surely, if if, the restrictions at the moment seem to be working at the moment, and the number of attacks is going down, and surely if there is, er, some evidence … For example, you’d be familiar, Dr Hugh Worth, the head of the RSPCA, in 2009 said that there was absolutely no place for these dogs in Australia. He said they were time bombs. He said they should be banned. Now everyone here, I’m sure, who has any knowledge of animal welfare issues knows who Hugh Worth is. He is a very respected veterinarian. The RSPCA is an organisation that is there to prevent the cruelty to animals and protect them. If he is saying it, surely, surely not getting your personal favourite breed of dog is a small price to pay for knowing that kids could be safer. And adults,” say Joe Hildebrand.
“What do you think about that Melanie?” says the host.
Wow, give poor Melanie a chance. There’s about a million points there.
Melanie tries, she says that while ‘the laws appear to be working’ you will probably see that attacks haven’t gone down, but they have stayed the same or risen. She asks if we want to see dog bites to go down, or do we want to see pit bull bites to go down? Maybe pit bull bites are going down, but surely we want dog bites to be going down full stop.
Then Melanie got cut off before she got a chance to say all I would’ve:
This is not about people having a dummy spit for not being allowed to own pit bulls. The issue is that banning pit bulls does not make kids and adults safer.
There is not a reduction in dog attacks in all, just dog attacks by restricted breeds. So the community isn’t safer from a pit bull ban, they’re just less likely to be bitten by them. (Just like if you banned Ferraris, no more people would die from Ferrari related accidents. But people would still die in car accidents.)
Dr Hugh Worth is known as Dr Hugh Worthless by many animal-lovers in Australia. ‘Nough said.
Joe Hildebrand talks about serious pit bull attacks, and includes footage of a guy severely mauled by three American Staffordshire Terriers. He argues that the severity and frequency of these attacks should see the breed banned.
Again, no real chance of reply is provided. So my reply would include:
Hi. The dogs in that video are American Staffordshire Terriers. Not pit bulls.
Also, people die from weimaraner and jack russell bites, too. The media often fails to report on these attacks, or when they do so, they report in a different way. (For example, Buster the golden retriever attacked 4 people and the media at the time mostly reported on ‘why would a golden retriever attack?’ instead of the ‘golden retrievers should be banned’ approach we see after bull breed attacks.)
“So you’re not hearing of labradors, or maltese terriers, or toy poodles causing this damage…” says Sarah Harris.
Ambulance guy (from the expert panel) says he’s been to attacks of lots of different breeds. He says that he “can’t tell the breeds apart to be honest” and “In my experience… all dogs can bite. It doesn’t matter what kind of breed it is” and ‘the bigger the dog, the bigger the bite’.
I would elaborate this response, if I had the opportunity, to when you say ‘you’re not hearing of’ attacks by different breeds, that’s because you’re not reporting them.
It’s how you train the dog, surely?
Yay, a decent question! Ambulance guy says that he trains his dogs and doesn’t leave them alone with kids. Good advice!
“Brad can talk through how the behaviour works. I mean, are pit bulls aggressive dogs?”
Brad was methodical in his response to this question.
It’s about preventing dog bites. You want the community to be safer, right?
Are you attached to the how (BSL)? Or are you attached to the outcome?
When we look around the world at measures used to reduce dog bite statistics to as low as possible, we see that success is based on behaviour-based strategies and not breed.
“You’ll never get rid of [dog bites] – get rid of 400 breeds – right? It doesn’t really matter.”
“When we were talking about this last week, a 4 year old boy had been attacked and terribly mauled and there was a question mark over the fate of the dog who did that. And I must say, as a mother, I would want that dog destroyed. I wouldn’t want to be standing up let’s protect this dog because he’s just.. severely injured this child, potentially could’ve killed this child. To me, isn’t that more of the issue?”
Brad answers this one as well.
This is the result of a ‘tragic convergence of errors’.
The dog was chained – chained dogs are more likely to bite.
The babysitter was there – not the owner.
The dog was large – larger dog, larger damage.
The child wasn’t adequately supervised
Well done Brad, again.
Joe Hildebrand wants hands to be raised for anyone who thinks dogs that attack a child should be killed. (That is, he fails to acknowledge the factors affecting the likelihood of a dog bite, as described by Brad.)
There is no place in society for a dangerous dog. What makes a dog dangerous is based upon the behaviour of the individual.
The whole thing got a little bit messy, with Joe Hildebrand speaking over Brad and Brad refusing to be spoken over. In summary:
There is a perception in the community that dogs are dangerous and
NSW statistics show that the pit bull terrier is the most dangerous breed of dog.
Brad replied that:
Perception is only perception, and
Those statistics are invalid, and
It doesn’t matter: We know what causes dog bites, globally, and we know that BSL doesn’t work.
We were talking about whether a dog who attacked a toddler should be destroyed.
Dr O’Shea says it’s context based. A good call.
And this is where this exchange ends.
So do you think the expert panel was given a fair chance?
Establishing ‘aggressive breeds’ without using dog bite data: Using owner reports to establish the most aggressive dog breeds
In 2008, data was published on the ‘most aggressive dogs breeds’, with dachshunds, chihuahuas, and jack russells, coming out on top. Recently, various media reports having been reappearing on my newsfeed on this study, with titles like “The 3 Most Aggressive Breeds Revealed“.
Before we begin, please do acknowledge that I adamantly against BSL. I am heavily influenced by research and evidence and, currently, all the evidence points to breed specific legislation never being effective in reducing the incidence of dog bites, in any place globally.
That being said, because I am interested in science, I am interested in studies like this.
So what can this study teach us about aggression in particular dog breeds?
A Jack Russell Terrier: in the top three aggressive breeds according to this study.
The Flaws in Breed Aggression Research
Aggression is a difficult characteristic to assess in dogs. There are a variety of methods that researchers have used, and all have their ‘downsides’.
Using dog bite statistics is not the best course, as most dog bites go unreported, the dog breeds involved cannot be verified and, even if they are verified, it is impossible to understand how many dogs of that paricular breed exist in the community.
If you’re only looking at caseloads from behavioural clinics, then this data is likely to be biased. Generally, people with larger and more dangerous (because of their size) dogs are more likely to seek help, as are people who have dogs aggressive to members of their family. (This article doesn’t mention it, but finances also play a role here – only those owners with the finances to attend behavioural clinics would be represented in such a study.)
There has been some popularity in behavioural tests (cough – D&CMB proposal – cough) where they do threatening or scary things to a dog and score their responses. The problem with this is how this actually relates to the ‘real world’ and the aggression the dog displays in everyday life.
When you ask owners about their dog’s behaviour, their experiences and responses are subjective. And ‘experts’ aren’t much better, with many of them representing ‘shared stereotypes’ whether conclusions from their own experiences.
In this particular study, C-BARQ was used. C-BARQ has a good record as being pretty reliable when it comes to asking owners what their dogs are like, temperamentally.
Members of 11 AKC club (‘club sample’) and vet clinic clients (‘online sample’) were invited to partake.
1,553 C-BARQs were completed by the club sample, with 29 excluded as they did not meet criteria.
8,260 C-BARQs were completed by the online sample, with 1,257 excluded for being mixed breeds or with no breed indicated, and 2,051 excluded as there was less than 45 of that breed represented – so in the end the sample was 4,952 responses for 33 different breeds.
They were rated on aggression towards strangers, owners, and other dogs.
The online sample and breed club sample differed in some ways. Breed clubs submitted more intact dogs, more female dogs, and older dogs than those in the online sample. Despite this, the results were quite consistent across the two samples.
Dog aggression was the most common and most severe type of aggression in the study, but dog aggression was not correlated with aggression to people. This supports the widely held view that ‘dog aggression’ does not indicate a risk to people. Similarly, aggression towards household-dogs was not associated with aggression towards other dogs or people. From the data in this study, more than 20% of Akitas, Jack Russell Terriers, and Pit Bulls had serious aggression towards unfamiliar dogs.
When it came to aggression towards people, the highest rates were found in smaller breeds, ‘presumably’ because aggression from smaller (and so more manageable and less dangerous) dogs is more tolerable.
When it came to aggression towards owners, more than half of the aggressive displays towards owners were associated with the owner taking food or something else away from the dog.
While fear in animals is associated with aggression, fear was not strongly correlated with aggression in this study. Some dogs were aggressive but not fearful, some were fearful but not aggressive, and some were fearful and aggressive.
A quote from the study on their findings,
“Although some breeds appeared to be aggressive in most contexts (e.g., Dachshunds, Chihuahuas and Jack Russell Terriers), others were more specific. Aggression in Akitas, Siberian Huskies, and Pit Bull Terriers, for instance, were primarily directed toward unfamiliar dogs. These findings suggest that aggression in dogs may be relatively target specific, and that independent mechanisms may mediate the expression of different forms of aggression.”
Further results on a more breed-by-breed basis (breeds listed alphabetically):
Akitas rated higher for aggression towards other dogs than other breeds.
American Cocker Spaniels rated higher for aggression towards their owners than other breeds.
Australian Cattle Dogs rated higher for aggression towards other dogs than other breeds, and also rater higher for aggression towards strangers.
Basset Hounds rated higher for aggression towards their owners than other breeds, but were below average when it came to stranger directed aggression.
Beagles rated higher for aggression towards their owners than other breeds.
Bernese Mountain Dogs were among the breeds least aggressive towards people and dogs, and ranked below average on stranger directed aggression.
Boxers rated higher for aggression towards other dogs than other breeds.
Brittanys were among the breeds least aggressive towards people and dogs, and ranked below average on stranger directed aggression.
Chihuahuas rated higher for aggression towards people (both owners and strangers) and higher for aggression towards other dogs than other breeds.
Dachshunds rated higher for aggression towards people (both owners and strangers) and higher for aggression towards other dogs than other breeds.
English Springer Spaniels rated higher for aggression towards other dogs than other breeds, and also rated higher for aggression towards owners. Showed bred English Springer Spaniels were more aggressive than field bred lines.
German Shepherd Dogs rated higher for aggression towards other dogs than other breeds.
Golden Retrievers were among the breeds least aggressive towards people and dogs, and ranked below average on stranger directed aggression.
Greyhounds were among the breeds least aggressive towards people and dogs, and ranked below average on stranger directed aggression.
Jack Russell Terriers rated higher for aggression towards people (both owners and strangers) than other breeds and higher for aggression towards other dogs than other breeds.
Labrador Retrievers were among the breeds least aggressive towards people and dogs, and ranked below average on stranger directed aggression. Field bred labradors were more aggressive than show bred labradors.
Pit Bulls rated higher for aggression towards other dogs than other breeds.
Siberian Huskies ranked below average on stranger directed aggression.
West Highland White Terriers rated higher for aggression towards other dogs than other breeds.
Whippets were among the breeds least aggressive towards people and dogs, and ranked below average on stranger directed aggression.
Warning against reaching conclusions on the genetic basis of aggression…
The authors caution, “Demographic and environmental risk factors for the development of canine aggression need to be investigated across a variety of breeds so that both generalized and breed-specific influences can be identified.”
So what do you think? Are these studies results consistent with your experiences?
Deborah L. Duffy, Yuying Hsu, & James A. Serpell (2008). Breed differences in canine aggression Applied Animal Behaviour Science, 114 (3), 441-460 DOI: 10.1016/j.applanim.2008.04.006
Should you breed from a dog that is dog-aggressive?
“Deez” was surrendered into rescue having almost-exclusively lived in a backyard for 2 years, with minimal interaction with other dogs. Despite this lack of socialisation, he was friendly with other dogs. While his breeder wasn’t what would be regarded as highly ethical, they obviously were producing dogs with good temperaments. His sociability with other dogs was the reason we were able to so easily place him into a new home – he now has another dog for company.
There’s four questions concerning that particular dog’s aggression that I would consider when elevating a dog’s suitability for a breeding program.
Firstly, if the dog is biting/attacking other dogs, is it illustrating bite inhibition by not actually doing damage to other dogs? If a dog is ‘attacking’ at a lot of dogs, but never doing damage, then this is a good sign that the dog is not intending to physically harm other dogs.
Then, how common is this type of aggression in this breed? Very common, uncommon, rare? In some breeds, all you can do is pick ‘the best of a bad bunch’. Complimentary temperaments in proposed matings are important, too (you wouldn’t put a ‘bad dog’ to another ‘bad dog’, for conformation or temperament).
Is the dog so aggressive to other dogs that you can’t achieve a natural mating? If the dog is not psychologically sound enough to have sex then it shouldn’t be bred from. Consider that many solitary species, like tigers, bears, rhinos, are generally territorial and aggressive to one another – yet, they still able to reproduce naturally. That is, the instincts associated with reproduction are strong enough to override a natural dislike to their own kind. Dogs, who are naturally social animals, should at the very least have a temperament conductive to natural matings.
Finally, a question to ask yourself as a breeder: Would you be satisfied if your puppy buyers ended up with a dog of similar temperament? That is, would you be proud to produce a dog with similar dog-aggression? Are you puppy buyers able to manage or train against dog-aggression? Dog owners want dogs to be ‘friendly’, and producing dogs with dog-aggression are likely to fall short of the owners’ expectations.
What do you think? Should a dog that has dog aggression be bred from? Under what circumstances?