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.

07/16/17
Litter Size - Can we predict it?

Litter Size – What the research says

Litter Size - Can we predict it?

There is an ongoing paucity in the literature surrounding most dog matters, and that means dog knowledge is often based on anecdotes and experience instead of facts and figures. Dog breeding is no exception. Breeders will tell you that they get bigger litters if x, smaller litters if y, that they’ll never mate a bitch if z. While personal experiences can provide case studies, I am interested in much bigger data.

Enter a Norwegian study looking at 10,810 litters.

This study used data held by the Norwegian Kennel Club to look at every litter registered in 2006 and 2007, across 224 breeds. Statistical analysis was then done to determine all the wonderful figures summarised below.

The aim of this study was to determine what actually makes a difference in litter size. (Litter size being the number of puppies born, alive or dead.)

Firstly, an overall average had to be determined. For this data set, the average litter size, considering all breeds, was 5.4 puppies.

For those interested in average litter size by breed: The largest average litter size was in the Rhodesian Ridgeback with an average of 8.9 pups per litter. The Toy Poodle and Pomeranian had the smallest average litter size – 2.4 pups per litter. And the Border Terrier (because I’m biased) had an average litter size of 5.1 pups per litter.

This study found that litter size was influenced by the size of the breed, the method of mating, and the age of the bitch. Litter size was not affected by season of birth, or the number of litters a bitch had had.

Size of the breed

This study examined dogs based on average breed size. They were classed as miniature breeds (<5kgs), small breeds (5-10kgs), medium breeds (10-25kgs), large breeds (25-45kgs), and giant breeds (>45kgs). Bitches were recorded against the average size of a dog for their breed and not specifically on the size of that given bitch.

“When looking at all the … litters…, mean litter size increased with the size of the breed. The mean litter size was 3.5 in miniature breeds, 4.2 in small breeds, 5.7 in medium breeds, 6.9 in large breeds, and 7.1 in giant breeds.”

The feature of larger dog breeds having larger litters is not a new thing – this phenomena is consistent across other studies. But this study is different as it found that it wasn’t just size of the breed that mattered…

Age of the bitch

The first analysis of this data showed no significance with the age of the bitch, however, once breed size was taken into account, there were two trends apparent:

  • In small and miniature dogs, young and old bitches had smaller litters than the ages in between.
  • In larger breeds, increasing age corresponded with decreasing litter size. (Young bitches of larger breeds produced the largest litters – unlike small and miniature breeds.)

Predicted litter size by the age of the bitch for the five different breed size groups from Borge et al. study.These results are a little different to other studies, which have shown smaller litter sizes as bitches get older. (As in, the results this study got for larger breeds was seen in all breeds in previous studies.) It could be that smaller sample sizes in other studies may have missed this, or that other studies used larger breeds as their data set instead of small or miniature breeds. One suggestion is that small breeds may not mature as quickly as previously believed, and so they’re not able to reproduce until they reach that mark. (To me, this kind of makes sense – considering small breeds often live longer, then it’s likely that they mature more slowly, too.)

Method of mating

Like the age of the bitch, the first analysis on the data didn’t show a significance change in litter size based on mating method. However, when the data set was adjusted for breed, breed size, and age, naturally mated bitches had significantly larger litters than those who had been AIed (either fresh or frozen).

A decrease in mean litter size of 0.4 puppies would be expected for litters conceived with AI with fresh semen and 1.3 for AI with frozen semen, both compared to natural mating.

Things that didn’t matter

The number of litters a bitch had previously didn’t influence the size of her litter. (However, older bitches normally had had more litters – and their age did influence litter size.)

The season the litter was born in did not influence litter size.

Conclusion

Size of the breed, age of the bitch, and the method of mating are three factors work together in determining litter size. It’s not one thing – it’s all three.

“… the size of the breed, the age of the bitch and the method of mating were found to influence litter size in purebred dogs when controlling for breed, with the size of the breed as the strongest determinant.”

This study is better than past studies in this area for its huge sample size, its variety of breeds, and the fact that it considers all puppies in a litter (not just those registered, as some past studies have done). In this way this study is unique. It is probably a pretty reliable data pool for purebred dogs, too, as 90% of purebred dogs in Norway are registered with their kennel club.

Things to consider regarding the vigour of the results:

  • It’s a retrospective study.
  • It does not include data from litters where all pups were born dead.
  • Calculating mean litter size is hard, because of % made up of small or large breeds. Small breeds are currently popular, so could perhaps pull down the mean litter size seen in this study. Studies done in different countries, with different breeds being popular, is likely to result in different results.
  • There is a relatively small sample of bitches who were mated not-naturally in this study, so the results should be interpreted cautiously, however the results are consistent with previous findings.
  • This study only groups dogs by weight – not by body shape. This might yield differences. (A neapolitan mastiff is really different to a greyhound.) And they group them by weight average of breed, not the weight of the individual bitch
  • This study looked at only two years and the researchers wonder if there might have been more variation in season of birth if there was more time taken into consideration.

In conclusion: Based on this study, breed size is the strongest determinant for litter size in a dog. The age of the bitch and the method of mating were also significant predictors of litter size. These three things interact, making litter size predictions difficult!

Acknowledgements:

Borge, KS, Tonnessen, R, Nodtvedt, A, & Indrebo, A 2011, “Litter size at birth in purebred dogs – A retrospective study of 224 Breeds”, Theriogenology, 75, 911-919.

Thank-you to Waldwiese Kennels for the cover image – a litter of longhair weimaraner puppies.

07/3/17
Canvas art - why you should choose to memoralise your pets with canvas.

Canvas Art for Pets

Canvas art - why you should choose to memoralise your pets with canvas.

The modern way to display art in homes is by canvas. While in the past, framed images have been the fashion, we no longer want our artwork to displayed in boxes on the wall. We like the infinity of canvas – the way there is no end, as though the whole image could consume the world.

The love of images-on-canvas has extended to our pets, too. Many homes are choosing to cover their homes in not just art, but photos of their beloved pets.

Besides the appealing look, there are other benefits to a canvas too:

  • Easier to clean – no glass where fingerprints can be laid, no moulding to attempt to dust in nooks and crannies. With canvas, you can gently vacuum, or use a damp cloth.
  • Easier to transport – no risk of breaking glass, and lighter (and cheaper!) too
  • Less choice – less choice is easier! Of course you can choose to size of your canvas, but you avoid having to make decisions about frames and matt boards.
  • More display options – Canvas can be propped up on shelves easily, while heavy frames risk slipping and could result in broken glass. Also, should the fashion ever change back to frames, canvas can be framed in much the way as flat art. No loss!
  • Cheaper – when you purchase canvas art, you are buying the complete work! No moulding, glass, or hanging guides required, so what you see on check out is what you get.

Recently, I received a canvas from TheCanvasFactory.com.au – an Australian distributor of canvas products. It was super easy to upload an image to the site, and it arrived quickly to my home. However, when it arrived, the image was a little ‘off’ – it seemed blurry in places. I contacted them and they quickly, and without promptly, sent me a second canvas at no cost. THIS one was great! I now have our wedding photo (including dogs, of course – they came to our wedding for photos) on display in our bedroom.

I would very much recommend TheCanvasFactory.com.au if you are looking for canvas products to adorn your own walls. They have good prices, diverse sizes, and great customer service.

A lovely border terrier artwork, on canvas.

A lovely border terrier artwork, on canvas.

01/30/17

Breeding Away from MMVD in Cavalier King Charles Spaniels

Puppy Buyers What You Need To Know about MMVD in Cavalier King Charles Spaniels

ResearchBlogging.orgThe health of many breeds was slammed in the documentary “Pedigree Dogs Exposed”, and one breed that received a barrage of criticism was the Cavalier King Charles Spaniel (CKCS or Cavs).

Heart issues are a problem in Cavs, and it can be fatal. The hearts of all mammals are made of a series of chambers and valves. It is a very synchronised organ and everything needs to work ‘just so’. During one particular condition, myxomatous mitral valve degeneration (MMVD), one of the heart valves ceases to function properly. Overtime, this puts pressure on the rest of the heart, and this leads to chronic heart failure. How individual dogs react to MMVD varies a great deal, and so prognosis after diagnosis is quite variable. The disease often progresses slowly. (If you more detail see this ACVIM factsheet.)

To understand the gravity of this problem, 37% of Cavs that die before 10 years of age do so due to MMVD. (From Swedish insurance data 1995-2006.)

Knowing that there was a problem, the Danish Kennel Club (DKCA) chose to act.

 

The DKCA Breeding Scheme

The DKCA brought in a mandated breeding scheme in 2002-2011, leading to 997 Cavs being examined in those years. Examination include asculation (stethoscope listening) and echocardiography (“echo”, sonograph of heart using ultrasounds) to evaluate the presence of murmurs in any indviidual cav. (Murmurs are predictors of MMVD progression, and have a genetic component.) Each dog was evaluated 1-4 times. There was a total of 1471 exams over the 9 years.

From my understanding, the DKCA required that Cavs be examined after 18 months of age to be approved for breeding. This approval would last until the dog is four years old and, to be bred after four years of age, they had to be re-examined and approved a second time.

To be approved, the dog had to have a MVP grade of two or less, and a mitral regurgitation murmur grade of three or less. If a dog had higher scores, they were excluded from breeding. After 2007, the criteria changed to become slightly more strict. It’s interesting when reviewing the data in this study that the largest number of unapproved dogs occurred in 2007, presumably as a result of this ‘tightening’ of regulations. While this must have been disappointing at the time, it’s a good way for the DKCA to encourage continual improvement without causing a huge reduction in genetic diversity.

The status of each dog examined became published and freely available on the DKCA website.

The DKCA would only register puppies from parents that had fulfilled the cardiac health criteria.

 

How good was the scheme?

This article, published in the Journal of Veterinary Internal Medicine, evaluated the study. Here, comparisons were made between scores of the beginning of the scheme to the end. They also categorised dogs as either approved by the breeding scheme (both dogs tested before mating), or unapproved (one or both parents unknown cardiac status before breeding).

Over the course of the study, they concluded that Cavs were at a 73% decreased risk of developing MMVD.

“A mandatory breeding scheme based on auscultation and echocardiography findings significantly decreased the prevalence of MMVD over the 8- to 10-year period. Such a breeding scheme is therefore recommended for CKCS.”

As a personal comment, I wanted to note that of the 1380 exams that met the criteria of this study, only 78 animals were excluded from breeding.

 

What would be better?

Being able to DNA test for MMVD would be brilliant, but even though we know this condition is highly heritable, DNA markers have not been established. DNA testing is not conceivable in the near future.

“Breeding restrictions or recommendations aimed at decreasing the prevalence of MMVd in CKCS have been developed in breeding clubs in different countries. The high heritability of the disease indicates that section against the disease could be successful.”

This study was retrospective, and only included animals over 18 months of age at their first examination, and excluded animals that were pregnant or lactating. Nine years is a long time, and there could have possibly be variations in scoring over time (despite this studying using clinical observers). A study with a greater sample size with less exclusions and more consistent scoring would always be better, but not necessarily highly achievable.

Interestingly, sometimes dogs can test better if there are changes in the dog. So, a dog’s heart may appear to have a murmur on one occasion, but if the dog changes body condition, heart rate, or both, then the second time the dog is asculated, it may not get the same reading. Therefore, testing dogs on numerous occasions would probably be best for consistency (but a difficult task in reality).

 

What does this mean for puppy buyers?

If you are wanting to add a Cav to your family, when talking to Australian breeders, the recommendations were made that breeders should be:

  • Having their breeding CKCS’s hearts examined annually, preferably by a specialist.
  • Not breeding from dogs that show a heart murmur at five years of age or younger.
  • Not breed any dog until they are 2.5 years old, especially if the parent(s) of the dog have murmur(s).

I asked a couple of Cavalier breeders on their recommendations, and have included them below as a starting guide for puppy buyers.

From Liz at Wandalier Cavaliers:

I think that it’s important to stress that [MVD] does appear to be random. That the level of deterioration, and the age of onset can vary greatly. But basically the later the onset, the better the prognosis. But you can have one dog with a heart murmur, and all the litter mates are fine. There’s also still no known mode of inheritance.

And from Barbara at Karhisar Cavaliers:

An important thing for those wanting to buy cavalier puppies is asking the right questions when contacting breeders. Sire and dam should both hold a minimum of current, clear heart & eye certificates from cardiologist and ophthalmologist. Breeders who are doing the official testing will be only too happy to name the relevant specialists and provide copies of the sire and dam’s health clearances.

When looking for parents who have certification, keep in mind that both parents should be cleared. In this study, there was only a significant reduction in risk for offspring if both parents were approved by the breeding scheme. Half the parents being approved is not good enough.

 

Where to for Cav breeding schemes from here?

While the results from this Danish scheme seem good, and a similar scheme in British showed promise as well, there was another in Sweden that didn’t have a significant effect. So, we can conclude that breeding schemes probably have a role in improving breed health, but exactly what the perfect breeding scheme may be is a bit of an unknown.

However, it is likely that mandatory breeding schemes are likely to be the only ones with oomph to bring about change. Schemes that aren’t mandatory haven’t yielded great results.

It’s important to note that not all heart murmurs are associated with heart disease. 6-10% of Cavs have ejection murmurs, and we shouldn’t exclude those from breeding as this would reduce genetic diversity.

So basically there needs to be further evaluation on ongoing breeding schemes to balance costs and benefits.

 

Reference:
Birkegård, A., Reimann, M., Martinussen, T., Häggström, J., Pedersen, H., & Olsen, L. (2016). Breeding Restrictions Decrease the Prevalence of Myxomatous Mitral Valve Disease in Cavalier King Charles Spaniels over an 8- to 10-Year Period Journal of Veterinary Internal Medicine, 30 (1), 63-68 DOI: 10.1111/jvim.13663

On an unrelated note, Some Thoughts About Dogs was proudly one of the Top 50 Dog Training Blog.