08/17/17
dog bites who gets bitten by which dogs

Which people get bitten by which dogs?

dog bites who gets bitten by which dogs

Dog bites are one of my niche areas of interest, so I when I came across this 2008 bite study, I was keen to read. The overall objective of this study was to work out the similarities between biting dogs and people injured by them, to be able to understand dog bites in such a way that public health could be influenced.

And dog bites are a bit public health problem. In 1986, dog bites were among the top 12 causes of nonfatal injury in the US. in 2005, an estimated 800 000 dog bites needed medical attention in the US. On average, 18 people die per year in the US as a result of dog bites. The number of reported dog bites is going up each year, suggesting this is a growing problem. (Though, personally, I think the number is probably going up to growing intolerance of dog bites in the community.)

So this study was a retrospective cohort study, looking at data for incidents that occurred in the 2002/2003 financial year in Multonomah County, Oregon. In this study period, 636 dog bites were reported to Animal Control Services, while there were 47, 526 dogs licensed in the county.

What followed was a whole lot of number crunching that I don’t entirely understand. From where I’m sitting, it looks like a fair bit of extrapolation went into the figures seen below, but without sampling every single household for dogs and other aspects, I’m not sure if there’s a much better way to go about it.

But regardless, onto the results…

The Biters

From this study, dogs were more likely to bite if:

  • They were of particular types (terrier, working, herding, and nonsporting),
  • They were sexually intact and male, and
  • They were purebred.

Instead of using dog breed, they used dog type, to try to avoid problems in identification. (For example, the general public has a hard time determining between a border collie and coolie, but they do know it’s some kind of herding dog.) The breeds listed above were more likely to bite than dogs that were sporting breeds, hounds, non-AKC breeds, and toy breeds. This study suggested that the dogs in the ‘problematic’ groups have instincts they’re likely to revert to if left untrained (which doesn’t ring true to me for the nonsporting group), and threat they are a ‘size and strength’ to cause damage (which doesn’t seem right considering the size of most terriers).

More intact male dogs bit than any other neuter/sex ratio. This is different to other studies I’ve reviewed.

It’s really perplexing that purebred dogs were more likely to bite in this study. I guess this goes to the breeding practices, but it’s curious to think that crossbreed dogs, presumably bred by people who are ‘accidental’ breeders, end up with less-bitey temperaments. Something for breeders to think about. While these dog factors existed, there was also a range of other elements to a dog bite.

“Factors that determine whether a dog-human interaction will result in a bite are complex and involve characteristics of the dog, the injured person, the owner, and the dog’s environment.”

The Owners of the Biters

Biting dogs were more likely than nonbiting dogs to live in neighbourhoods where the residents’ median incomes were less than the county median income value. If controlling for breed category and controlling for sex, “dogs living in census block groups that had incomes less than the county median were 1.5 times as likely to be reported as a biting dog than reported as a nonbiting dog”. When dog owner data was compared to population density, percentage sex by age, percentage nonwhite race, and percentage without high school diploma, there was still not an association with biting. It was correlated just with income!

So what’s going on here? What’s different in areas were less income? Less money spent on training? On fences? Different attitudes towards child raising? This study suggests that people in these areas may be inclined to select particular breeds (i.e. especially those with reputations for aggressive behaviours). (Though this study didn’t look at whether some breeds were more likely to be owned by different groups.) They also suggest that low income areas may socialise their dogs in a different way, and therefore change the bite potential of the dog, or perhaps they’re not trained or supervised in a way that minimises dog bite risk.

“In another study examining dog bite injuries in St Louis, Mo, bite injuries occurring in low income areas were attributed to large numbers of children playing outdoors, few homes with adequate fencing, poor dog control, and a high proportion of large-breed dogs owned for protective purposes.”

As a personal comment, in my experience, crossbreed large dogs are cheaper than small dogs or purebred dogs. This means low income areas are likely to own bigger dogs, and we know bigger dogs are more likely to have their bites reported. While studies of the past have looked at breed and sex-neuter status, this study reveals a new area for further research: block group income levels.

But there’s more: It’s not just about the dog and who owns it, but also where the bite took place.

The Place of the Bites

Dog bites occurred:

  • 35.1% of bites happened in the dog’s home or yard.
  • 23.4% of bites happened in ‘neutral territory’
  • 17% of bites happened in dog/victim household (i.e. the parties lived together)
  • 10.1% of bites happened in household of victim (not dog’s place)
  • 7.1% bites unknown place
  • 3.8% at “place of employment” – e.g. vet clinic, rooming facility, MCAC
  • 3.6% “Neighbour’s Property” (which could be grouped with the 35.1%)

This reinstates the idea that parents need to be extra vigilant when they are visiting houses with dogs.

Other Statistics

Other tid bits of interest:

  • Boys and girls aged 5-9 years had highest rate of injury, boys a bit higher (but not significantly so).
  • Of the 636 biting dogs, 49% had a license number. There are some estimates that less than half of all dogs are registered. (I really wonder what this kind of statistic would look like in Australia.)
  • 36% of dog bite victims didn’t know the dog that bit them. (The largest portion.)
  • But: Among children, 46% were bitten by the family dog.
  • More dog bites in summer months.
  • No significant difference between male and females being bitten.

Limitations

Like all studies, there are a number of problems. In this study, the results are limited by.

  • Not all dog bites will be reported. Dog bites are a reportable incident in Oregon, but the records are incomplete. There’s a problem with recording of dog bites. A previous study, referenced in this one, suggested that only 17% of bites are reported to any authority. (And while this may be the case, how else should we be analysing dog bites except through dog bite records? This model is probably the best we have.)
  • We know members of the public are not very good at reporting dog bites by breeds.
  • Dog license data can only be used as an estimate of breed-populations – especially because we know perhaps only half of all dogs are registered. Further, if owners of some breeds are less likely to license their dogs, the breed specific bite rates are further skewed.
  • When a large-breed bites, that bite is more likely to be reported and more likely to need medical care, meaning that there is a reporting bias that can increase the number of these dogs seemingly involved in incidents.

 

Conclusion

This study made recommendations for reducing dog bites:

  • Combined approaches from human medical communities, veterinary communities, and animal control to help foster healthy relationships between people and pets.
  • Focus on low income neighbourhoods.
  • Paediatricians to counsel parents (dog owning and not) on dog safety during routine medical visits.
  • Low cost spay neuter.
  • Education programs (perhaps through animal control).

“Innate tendencies dictated by breed, sex-neuter status, and size play a role in the potential of a dog to bite, but owners are ultimately responsible for their dogs’ action[,]… and need to make every effort to minimisze their dogs’ bite potential through obedience training; neutering; and supervision, especially around children.”

Source:

Shuler, CM, DeBess, EE, Lapidus, JA, and Hedberg, K 2008, “Canine and human factors related to dog bite injuries”, JAVMA, vol 232, no 4.

08/1/17
doggy iceblocks

Doggy Iceblocks

doggy iceblocks

One of my biggest tips for problematic dogs is to give them boredom busters. These are normally food based challenges that keep the dog occupied for a long period of time. This could be a good meaty bone, a kong toy, or a doggy ice block.

As many of my clients through Dog Consultancy have never heard of an ice block before, I thought I’d blog post instructions on making them. Not that they’re hard to do! Variations of this ‘recipe’ all work fine, but here is a starting point.

1. Select a container

Choose an appropriate sized container for your dogs. I have small dogs, so I generally use plastic tubs for dips that are about 150g or so. Larger dogs could get margarine containers, up to ice-cream sized containers. Make sure you choose a container that is flexible, as you want to be able to pop out the frozen treat in the end. If the plastic is to rigid you might have trouble doing this.

2. Smear something tasty inside

Once you have your container, smear something tasty around the edges of the container. Suggestions could be:

  • vegemite
  • peanut butter
  • mince
  • canned cat or dog food

As long as it is safe for dogs to eat, and your dog likes to eat it, the options here are endless.

A small plastic container with canned puppy food pressed along the bottom to create a tasty layer.

A small plastic container with canned puppy food pressed along the bottom to create a tasty layer.

This is ‘kibble stock’. Dried dog food was placed in water, then microwaved for 30 seconds or so. The kibble has broken down into slush and made a stock.

3. Make up a stock

We are now going to fill the tub with flavoured water. Suggestions include:

  • commercial stocks
  • vegemite stock (vegemite melted into boiling water)
  • microwaved kibble (put a small amount of kibble into water, microwave until kibble becomes pulpy and water becomes stock-like)

Gently pour stock into your tub, making sure you don’t disturb your tasty layer. Leave enough room in the container to…

4. Add further treats

Add to your ice block anything that your dog might like. If you dog is new to ice blocks, leaving something tempting hanging out of the ice block as a ‘starter’ works well. Suggestions for further treats include:

  • pigs ear
  • chicken neck
  • dog biscuit
  • carrot
  • dry kibble
  • a toy like a ball

These two doggy iceblocks are ready to be frozen. They are made of kibble-stock with dog biscuits, smackos, and dried liver suspended in the liquid.

5. Freeze

Place carefully in your freezer, to avoid gross spillage, and then freeze at least overnight. Once they’re frozen, you can push them out and store them in a most space-conserving way, each necessary.

6. Dispense!

Now, whenever you go out, or your dog needs to be occupied by themselves, take out one of your pre-frozen doggy iceblocks and let them have it! Keep in mind these do make quite a mess, so they’re probably best as an outside meal, or fed in a crate where there’s minimal risk of spillage.

Two frozen ready-to-eat doggy iceblocks. The one in the foreground has a lambs ear sticking out. The one in the background is inverted, so you can see the frozen 'tasty layer' of canned food.

Two frozen ready-to-eat doggy iceblocks. The one in the foreground has a lambs ear sticking out. The one in the background is inverted, so you can see the frozen ‘tasty layer’ of canned food.

But my dog’s allergic to…

If your dog has any food intolerances, just use whatever from this list your dog can eat and leave out everything else. I have made doggy ice blocks for dogs before on special diets, and I have made it just out of microwaved kibble and stock made from that microwaved kibble.

But my dog needs to lose weight…

You control what you put in your dog’s ice block! Cut out parts of your dog’s dinner and place it in the ice block instead. Some food-orientated dogs are happy to have a stock-iceblock, with not much to it except slightly salty water. This is the low-calorie option.

They’re not the most attractive thing to photograph, but dogs love them! Please comment if you have any extra ideas of things to put in your dog’s iceblocks.

10/7/14

Novelty (or Practical Habituation)

I have been thinking a lot of late about novelty in dog training. More technically, I’ve been thinking about habituation (i.e. a type of non-associative learning) and how it works in the ‘real world’ for changing dog behaviour in simple ways.

 

Dogs can habituate to water.

Dogs can habituate to water.

When I was a kid, I grew up with a chow chow called Ted. Ted mostly lived in the backyard, but as a child, I one day decided that Ted was going to get a walk every day. And so I walked him every day for about a month (before moving onto the next project, as kids do). Ted started the month with enthusiastic jumping regarding the prospect of a walk. He also vocalised a little bit. By the end of the month, Ted had the lead put on with no fuss, no jumping, no noise, and soldiered on for the walk.

Sure, I could’ve implemented some kind of training regime. But, in reality, I didn’t. Ted started the month thinking walks were novel, and his behaviour stemmed from this novelty. At the end of the month, he was habituated to the walk. Previously, the outside world meant a lot to him and resulted in him getting aroused. By the end of the month, it meant close to nothing, and his arousal levels were far less.

 

Then there’s our foster dog Bandit. I picked him up from his surrendering family, one hour from my house, and drove him home. He drooled, paced, and stressed the whole way home. On ever subsequent car trip, Bandit’s behaviour got more mild. Recently, I drove him to a boarding facility about 20 minutes away, and he was laying, asleep, by the time we got there. No training went into this. Bandit just ‘got over it’ because he habituated to the car – it became less novel.

 

I find many outside dogs are often ‘over the top’ when they meet people, and I think this is a novelty thing, too. If dogs only see people on an occasional basis (i.e. when you go outside), of course they’re going to be excited to see you! If they were inside and saw you constantly, their responses are going to be more mild. Indeed, with most attention seeking behaviours (e.g. jumping up, head nuzzling, vocalising), these behaviours will decrease if the dog has sufficient attention to start with. If attention is given liberally, the resource becomes less important, and the dog’s behaviour changes.

 

I think the concept of novelty is often overlooked in dog training. Sometimes, dog behaviour will ‘get better’ simply because the novelty of something wears off.

Doing many varied things often can do more than maintaining socialisation – it can reduce novelty and so also decrease undesirable behaviour associated with that novelty.

09/3/14

A Link Between Desexing and Reactivity

ResearchBlogging.orgWhile 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.

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 active
  • 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

Further reading:
Desexing: It’s bad for Vizslas too
Is desexing a cult?
Desexed dogs – 2.6 times less likely to bite!
Why would you NOT desex your dog??
Golden Retrievers: Cancer if you do, cancer if you don’t

07/1/14

Desexed dogs – 2.6 times less likely to bite!

Australian Veterinary Association makes this claim, in its PDF “Dangerous Dogs – a sensible solution“:

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.

 

avadesexing

 

 

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.

Where is the Australian data-set?

Where is the study that controls for factors such as selectionsocialisation, and socio-economic factors?

 

What the AVA should really be saying is:

According to one study conducted in Denver, USA, 23 years ago, entire dogs were found to be 2.6 times more likely to deliver a bite (that required medical treatment) to a stranger than desexed dogs.