Category Archives: Dog Health

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.

06/14/16

New Research on Early Neutered German Shepherds and Joint Disorders

New Research on Joint Disorders in German Shepherds

 

ResearchBlogging.orgIt’s very exciting how there is growing research on desexing in dogs, including age of neutering, and its implications on health. In the past, I have blogged on how desexing in German Shepherds is linked to reactivity. The latest study, published last month, looks at bone disorders, cancers, urinary incontinence, and pyometra in German Shepherds.

Many of the arguments for desexing dogs has been around population control instead of health matters – but obviously health does matter. We want dogs to be healthy.

This retrospective study looked at the health of 1170 German Shepherds. It included the analysis of vet records over 14.5 years (2000-2014). For each incidence of disease, the dogs’ records were followed for eight years, except in the case of mammary cancer, which was followed for eleven years. The data on the incidence of joint disorders and cancers in the German Shepherds was compared beside their sexes, and their neuter-age.

 

Joint Disorders

The biggest problem with early aged desexing in this breed, according to this study, is an increased risk of joint disorders. For example:

  • 6.6% of intact males had one or more joint disorders, but for dogs that were desexed before 6 months, 20.8% had one or more joint disorder. So joint disorder incidence was three times greater in dogs desexed before 6 months than intact dogs. For dogs that were desexed between 6-12 months, the incidence of at least one bone disorder was 16.4%.
  • Similarly, 5.1% of intact female had one or more joint disorders, but for bitches that were desexed before 6 months the incidence was 12.5%, and for bitches that were desexed at 6-11 months the incidence was 17%.
  • Of the joint disorders considered, Cranial Cruciate Ligament Tear was most highly correlated with early desexing. In entire dogs, hip dysplasia was most commonly seen.
  • For desexed dogs, rates of hip and elbow dyplasia was greater than entire dogs, but this difference was not statistically significant.
  • There was no difference between the body condition scores (i.e. fatness) between entire and neutered populations – so it’s not obesity that has caused these problems.

 

But why do German Shepherds have an increased incidence of joint disorders when they’re desexed before one year of age?

If a dog is desexed before one year of age, the growth plates of the dog are unlikely to have closed. (That is, the bones are still growing.) With the removal of hormone cues through the removal of gonads, the bones are likely to grow longer than they ‘should’, which disrupts joint alignment. This disruption leads to joint disorders such as those found in this and similar studies.

However, this research did not just look at bone disorders.

 

Cancer

Unlike previous studies on cancer in other breeds, there was no statistically significant differences between neutered and entire animals. However, in terms of mammary cancer (which was only considered in bitches), 4% of intact females got mammary cancer, but <1% got mammary cancer if desexed before one year of age. The paper notes that mammary cancer seems to be uncommon in German Shepherds and refers to a recent meta-analysis that found the protective factor of neutering in terms of mammary cancer to be weak.

In terms of other cancers there was no significant differences. (My own note though: This study found that only 14% of the entire bitches were used for breeding. Lactating is a protective factor against mammary cancer, so I would suspect that if more of these bitches were breeding bitches, the rate of mammary cancer may have been lower again.)

 

Bitch-Specific Conditions

Urinary incontinence was seen at a rate of 7% in neutered bitches, but was not seen at all with entire bitches. (Urinary incontinence was not considered in males.) The mean age of onset of urinary incontinence in early neutered females was 5.2 years.

Pyometra in intact females was seen as a rate of 2.5%.

How does this compare to other research?

It’s important to note that this new data adds to our growing understanding of desexing implications. This study references:

  • A 2014 study saw that Golden Retrievers and Labrador Retrivers were, generally, more likely to have a joint disorder the earlier they were desexed.
  • A 2013 study saw that Golden Retrievers that were early desexed had more hip dysplasia, cranial cruciate ligament tears, and lymphosarcoma. Desexing, regardless of time, increased the rate of at least one cancer by 3-4 times.
  • Another 2013 study found that, in Vizslas, the incidence of cancers was high in desexed dogs (except mammary cancer – where incidence was low).
  • Another 2013 study found that neutered male and female dogs were more likely to die of cancer than intact dogs.
  • A 2011 study that found that, in several breeds, the incidence of mast cell tumours was four times greater in spayed females as opposed to intact.
  • A 2008 study that saw that desexing before 12 months of age saw joint disorders (such as hip dysplasia, cranial cruciate ligament tears, and elbow dysplasia) occuring at 2-3 times higher rates than in intact dogs.
  • A 2007 study linked early desexing with risk factors for cranial cruciate ligament tears.
  • A 1999 study found that cardiac hemangiosarcoma was four times more common in spayed females than those intact.
  • A 1998 study, looking at several breeds, saw that osteosarcoma was two times more likely in neutered dog compared to intact dogs.
  • A 1988 study that found that splenic hemangiosarcoma was two times more likely in spayed females than intact.

The researchers involved with this study have been adding great data to the neutering/spaying discussion. They have previously published articles on Labrador vs Golden Retrievers and Golden Retrievers, and these articles had similar findings. (Though German Shepherds did not seem to be as cancer prone as the Golden Retrievers.) As all these studies are using vet clinic data, it is not known how similar or dissimilar the strains/lines are – so the sample could be genetically diverse despite being the same breed.

But it seems that, for German Shepherds, it is far better to wait until dogs are twelve months or older before desexing, if desexing is chosen at all. I’ll end on a quote from the paper:

As shown in this study, delaying neutering until the dog is at least a year of age appears to avoid the increase in risks of joint disorders is associated with neutering. This is a consideration for joint disease control that is immediately available.

 

Reference:
Hart, B., Hart, L., Thigpen, A., & Willits, N. (2016). Neutering of German Shepherd Dogs: associated joint disorders, cancers and urinary incontinence Veterinary Medicine and Science DOI: 10.1002/vms3.34

 

Further Reading:

Early Neutering Poses Health Risks for German Shepherd Dogs, Study Finds

A Link Between Desexing and Reactivity

Labs and Goldens: Goldens Get Cancer Better

Desexing: It’s bad for Vizslas, too

But Mammary Cancer!

Why would you NOT desex your dog?

03/1/16

Eat Less, Live Longer

Eat less, live longer

 

ResearchBlogging.orgLast year I went to a Primal Paws workshop in Adelaide, and Dr Jamie mentioned research which suggested that dogs that stayed skinnier lived longer healthier lives. Obviously, I had to know more, so I found the 2002 paper on Labradors.

Young Black LabradorThe basic design of this study (published in 2002) involved 48 labradors. Each labrador was buddied with another labrador at 6 weeks of age (choosing a buddy based on sex and body weight), and then one pup in the pair was fed 25% less than the other dog in the pair throughout life.

The focus on his study was basically to see the effect that 25% less food had on longevity and other illnesses in dogs. Apparently, many other studies have been done, primarily on rodents, that have shown that less food (regardless of many other variables) results in longer living and healthier animals. However, this research hasn’t been conducted on larger mammals. (This is the first study, that the authors know of, on dogs. Research on primates is ongoing.)

Each year, for at least 14 years, the dogs alive had bloods taken and body composition scoring. Also, their deaths and any diseases that occurred were recorded alongside the year of acquisition.

 

The main points:

  • Dogs that had less food’s median life span was significantly longer.
    Dogs who were fed less had a median lifespan of 13 years, compared to 11.2 years in their partners.

  • “The onset of clinical signs of chronic disease generally was delayed for food-restricted dogs.”
    For dogs who had oestoarthritis (which was 43/48 dogs), 43 of these dogs required treatment. For controlled fed dogs, first treatment was needed from 6.8 years to 12.9 years. In the restricted fed group, first treatments was needed from 7.9 years to 14.1 years. Mean age was 10.3 in controlled group and 13.3 in restricted group, which was statistically significant.
    39 dogs required treatment for 1 or more chronic conditions. “Mean age to which 50% of the dogs in each group survived without requiring treatment for a chronic conditions as significantly lower for the controlled-feeding group than for the restricted-feeding group.”

  • ”No signs of nutritional deficiency (eg, progressive weight loss and general or specific clinical signs of a nutrient deficit) occurred during the study.”
    It’s important to note that, even though 24 dogs were fed a lot less food, they were still healthy!

  • Dogs in both groups had increased body condition scores (i.e. were fatter) from 6-12 years.
    This is just an interesting tidbit that illustrates a lull in the body’s metabolism at this particular point of time.

 

Problems

It’s hard to know whether this study will be replicable in different breeds or different genetic stock. Considering the history in the duplicity of results in other species, I think we can be pretty confident these results are solid. However, more research does this would be great.

Even though 48 dogs is a pretty good number for a sample, a bigger sample size is always better.

One question I found myself asking throughout this is, if it’s better to feed less food of a higher quality to maintain weight, instead of more food of poor quality? This would also be a good area for further research.

Indi mourns over the understanding that it's better for her to have 25% fewer chips.

Roxy mourns over the understanding that it’s better for her to have 25% fewer chips.

 

Take home points:

  • Feed your dog less. It might live longer.
  • Feed your dog less. It might be longer before it needs treatment for oestoarthritis (if they develop the condition).
  • Feed your dog less. It might be longer before it needs treatment for any chronic condition.
  • Feed your dog less, especially once he turns 6 years old.
  • Point from the actual text: “We recommend that for purposes of health and longevity, dogs be fed to maintain a body condition score less than 5.”

I’ve never been happier with my decision to keep my dogs at a lean weight throughout life.

 

Reference:

Kealy RD, Lawler DF, Ballam JM, Mantz SL, Biery DN, Greeley EH, Lust G, Segre M, Smith GK, & Stowe HD (2002). Effects of diet restriction on life span and age-related changes in dogs. Journal of the American Veterinary Medical Association, 220 (9), 1315-20 PMID: 11991408

 

Further reading:

How to Reduce Your Dog’s Weight

02/24/16

CECS is a Gluten Sensitivity

The idea that CECS is a Gluten Sensitivity has been presented by recent research.

They were actually quite confident with the link between the two, saying in the research,

Canine epileptic cramping syndrome in [border terriers]s is a gluten-sensitive movement disorder triggered and perpetuated by gluten and thus responsive to a gluten-free diet.

This is pretty exciting stuff! CECS (short for Canine Epileptoid Cramping Syndrome, or sometimes called ‘Spike’s Disease’)  is an unusual condition found almost exclusively in border terriers. These dogs are normal dogs except for when they have an ‘episode’ or a seizure. During an episode, the dog will ‘cramp up’. Typically, they remain conscious, but can’t walk, and sometimes appear worried following an episode.

Chip, a border terrier that does not have CECS

Chip, a border terrier that does not have CECS

So far, there has been no real diagnostic test or explanation for the condition. In December 2013, a study looked at CECS, but it was an owner-survey, information-gaining exercise. Which is important, but doesn’t give us answers!

It was so important that it actually spurred this research. In the December 2013 study, 50% of dogs were found to ‘respond’ (i.e. have less episodes) on a gluten-free or hypoallergenic diet.

So now let’s welcome this lovely small study titled ‘The Clinical and Serological Effect of a Gluten Free Diet in Border Terriers with Canine Epileptoid Cramping Syndrome‘, which begins to look at how we can both diagnose and treat CECS. Exciting stuff!

The aim of the study was to work out if a gluten-free diet would effect dogs with CECS. Not only did the researchers want to know if the dogs stopped having episodes, but if their blood looked different with and without gluten. Naturally, they wanted to know if these things were correlated.

The dogs involved were 6 border terriers (an equal mix of male and female). Each dog:

  • Had had CECS for at least 6 months
  • Had been diagnosed with CECS via veterinary observation (including video)
  • Had had at least 2 CECS episodes
  • Had not tried gluten-free diets before

For interest sake, the average age of onset for CECS in this small sample was 2.6 years.

Winnie, another border terrier who does not have CECS

Winnie, another border terrier who does not have CECS

Once recruited, the dogs had blood taken and the owners were given instructions for the dog going on a total gluten-free diet (Hypoallergenic Canine Dry from Royal Canin). The dog underwent a general physical examine (and some dogs went through more intensive procedures, owners consenting) and all were determined to be healthy, beyond the presentation of CECS.

The blood was again taken at 3, 6, and 9 month periods.

The blood was tested for antibodies which are considered important in diagnosing gluten sensitivity in humans.

The blood of non-CECS border terriers was also taken and tested.

The owner was asked to keep a record of the incidents of CECS in their borders.

Are you ready for the results? They’re pretty compelling.

So all that changed in these border terriers’ lives was that they were put on a completely gluten free diet. With this one change, all of the borders terriers, when they adhered to the gluten free diet, stopped having seizures within 4 weeks. Three dogs did not have seizures at all once they started the diet.

Two dog owners, upon completion of the trial, accidentally fed their dogs treats with gluten… And the dogs had seizures again. So not only did a gluten free diet stop seizures, the reintroduction of gluten caused seizures.

Now let’s talk about “Dog 6″. Dog 6′s owner is the epitome of why these kind of studies, where dogs are left with their owners, are hard work! Throughout the study, Dog 6 was a dog that continued to have seizures. Dog 6′s owner presumably fed the dog the gluten free diet, but then allowed the dog to continue to graze on horse poo when out and about.  This issue wasn’t identified until late in the study and so Dog 6 was excluded from the serum results listed in this article. However, when Dog 6′s owner actually did was they were told and stopped the horse poo eating, Dog 6 stopped having seizures too! When Dog 6′s blood was tested 3 months after the study ended (but 3 months into the owner actually doing it right), that dog’s blood results was consistent with the other dogs, and it too had ceased having episodes.

Why is this study such a big deal?

Up until now, we have had no way to diagnose nor treat CECS. (In fact, one of the criteria established in the 2013 study of CECS indicated that if a dog fails to respond to epilepsy medication then it probably is CECS. Nice to know, but not a great deal of help.)

The blood results from these dogs showed high levels of relevant antibodies in affected dogs while they consumed a diet with gluten. The presence of gluten-associated antibodies could be used to diagnose CECS.

Clearly, a treatment has been identified too: avoid gluten!

Other areas that are of interest:

  • Signs of gastrointestinal upsets could be a sign of gluten problems, or of future CECS. Vomiting, soft stools, or belly grumbling was reported in 2 of the dogs featured in this study. The presentation of belly problems and CECS together can be an indication of just one problem – gluten sensitivity!
  • The story of ‘Dog 6′, to me, really shows the importance of owners in being vigilant. I feel that many dog owners take a rather lazy approach to food elimination diets, but elimination means to completely remove. If you don’t completely remove, you can’t say that it’s been tried!
  • In humans, celiac disease has sometimes been associated with a rash… Which makes me think back to the correlation between CECS and skin-conditions in borders identified in the 2013 study.

Another quote from the study:

These investigations support the hypothesis that CECS is a manifestation of gluten sensitivity, making this the first [sudden onset] movement disorder in veterinary medicine with a serological link to gluten.

What research from here?

This is a very small study, and it’s important that we do more research before making solid conclusions. This study itself suggests further research:

  • With a larger sample size
  • More research into the correlation of gastrointestinal upsets and CECS
  • A double-blind randomised placebo-controlled trial

But in the meantime, while we’re waiting to know more, these researchers (and I!) recommend that, if you have a border terrier with CECS, you switch the dog to a diet that eliminates all gluten foods.

 

Reference:

Lowrie M, Garden OA, Hadjivassiliou M, Harvey RJ, Sanders DS, Powell R, & Garosi L (2015). The Clinical and Serological Effect of a Gluten-Free Diet in Border Terriers with Epileptoid Cramping Syndrome. Journal of veterinary internal medicine / American College of Veterinary Internal Medicine, 29 (6), 1564-8 PMID: 26500168

 

Further reading:

Gluten Sensitivity Triggers Epileptoid Cramping Syndrome in Border Terriers

 

CECS is a Gluten Sensitivity

 

08/27/15

Flea Prevention in a Foster Home

Anyone who has had fleas in their house before knows what a nightmare it is – for the humans and the dogs. The clean up following a flea infestation is very painful as well.

In coordinating a dog rescue for about seven years, I have got flea control down to an art. Here are my suggestions on ensuring that foster homes stay free of fleas.

When a dog enters care and has evidence of fleas (e.g. flea dirt around their groin), or for any dog that has come from a pound environment, flea treatment and prevent starts on pick up.

  • As I put the dog in the car, I treat with a spot-on flea treatment for dogs (like Frontline).
  • In the case of multi-dog transport, then all dogs in the car are treated with a spot-on treatment.

Once the dog has vacated my car, I then have to make my car flea-free. I use bug spray on pretty much everything. This includes bug-spraying:

  • Each side of the bedding the dog had in the crate.
  • The internal surfaces of the crate.
  • On all surfaces in the car, including in particular fabric surfaces.

Any bedding the dog used then goes either straight into the wash, or, if soiled, into a secured bag and into the bin.

Any other pets in the new foster household should be treated with a spot-on as well.

Following these steps should help flea infestations taking hold in a foster home. If, however, a dog ‘sneaks’ fleas into the house, then you will need to take remedial action. My process is:

  1. All animals in the household are dosed with a flea treatment.
  2. All bedding occupied by the flea-infested dog is treated with bug spray and washed.
  3. All areas of the house are vacuumed.
  4. All surrounding areas the dog came into contact with (like carpets, couches, etc) are doused in bug spray. I particularly concentrate the bug spray in nooks (e.g. under and behind furniture) and on the thresholds of rooms (e.g. in doorways).

It took me quite a few years to work out the exact method for getting a handle on flea infestations. I have learnt that prevention is easier (and cheaper!) than cure. Despite having some close encounters (such as foster dogs sneaking in their flea-visitors), I have never had a major problem in recent years. I put it down to these techniques.

Do you have any additional ideas on controlling fleas in a foster home?

 

Other posts of interest:

5 Ways to Keep Fleas Out of the House

Parasite Treatment Comparisons

Oral Flea Treatment Most Effective in Dogs