By Dr Miriam Carone / Pawsitive Coach, MBBS, GPST, IMDTB
Breeding dogs for specific physical and behavioural characteristics perceived as desirable, such as in the case of toy dogs or dogs with endearing physical features, or practical, such as in the case of working dogs, has led to the rise of breeds with specific traits and genetic pools, some of which are known to increase the risk of health issues (1).
While it is generally recognised that inbreeding amongst first degree relatives is a risky approach, and so it is relatively uncommon, there is more controversy about whether breeding per se is to be blamed for hereditary health problems.
Perhaps the most recognised example of breed-related health complications is that of brachiocephalic breeds such as pugs, which are prone to breathing difficulties or brachycephalic obstructive airway syndrome (BOAS) (2) and are generally considered less healthy overall than other breeds, including high rates of obesity and corneal disorders (3).
Other notable examples of breeds known to have a genetic predisposition to health issues are dwarf breeds such as Dachshunds, which are prone to intravertebral disc disease (IVDD) (4), and some breeds that are more predisposed to cancer (5), such as Flat-coated retrievers and Bernese Mountain dogs which are prone to malignant histiocytosis and Irish Water Spaniels which are prone to lymphoma and lymphosarcoma (6).
Importantly, however, we must note that these conditions, and in fact most health conditions, are all multifactorial, and not solely inherited, and do not necessarily statistically affect all purebred dogs more than mixed breed dogs (7).
If on one hand, breeding has led to a higher incidence or the genes which cause a predisposition to certain health issues, it would seem reasonable to think that responsible breeding, which includes genetic testing and objective health assessments before deciding whether an animal should be bred, could lead to lower incidences of said genes and an overall healthier population of dogs. Indeed, genetic screening is often used to screen for recognised genetic mutations that lead to disease, such as screening for progressive retinal atrophy (PRA), a recessive condition with significant variability in genetics (8).
The concept of selectively breeding for ‘healthier genes’ could be considered slightly over-optimistic in that, firstly, many genes and factors that lead to disease have not yet been identified or cannot be easily tested for, and, secondly, many animals that seem healthy may develop a disease later in life, after they have already been bred.
For example, whilst parental screening exists (by the means of X-rays) for IVDD, there is no way to guarantee that a puppy will not develop it later in life, owing to its multifactorial aetiology (9).
Indeed, some veterinarians such as Dr Dunbar advocate for only breeding male dogs once they reach old age, as they have ‘proved’ to be of good health. This rule is not commonly followed and is certainly difficult to follow when it comes to female dogs, as even though they do not undergo a menopause as human females do, their fertility does decline with age owing to a reduced frequency of estrus phase (10).
The recent Covid-19 pandemic has seen a ‘puppy boom’ (11), accompanied by a rise in backyard breeders and puppy farming. Unsurprisingly, the number of dogs surrendered to shelters has sadly also skyrocketed, and many of these dogs have behavioural issues relating to poor breeding standards and/or poor socialisation.
According to the Royal Veterinary College, prospective owners were more impulsive in the purchase of their companions, more likely to be first time owners, more likely to buy a puppy aged less than the recommended eight weeks, more likely to have had their puppies delivered, and less likely to have purchased the puppy from a Kennel Club registered breeder or one that performed health testing (12).
All of these factors undoubtedly have potential to affect the dogs’ health and have likely contributed, together with the sheer rise in number of dogs, to the increased demand for veterinary care. It will be interesting to see whether the incidence of inherited breed problems rises in the next few years following the pandemic, though it will be difficult to isolate breeding itself as a cause for it.
However, with the increasing awareness of the risks of improper breeding and the new legislations against puppy farming, such as Lucy’s law (Lucy’s Law - Gov.uk, 2021), it is hoped that the overall health of human-bred dogs will improve in time.
Overall, while selective breeding has likely led to a rise in some genetic and multifactorial conditions in the past decades, there are huge potential benefits to selective breeding, including behavioural, structural, and physiological advantages, but only if the breeding occurs with canine welfare as a top priority, rather than aiming to achieve aesthetically desirable traits or simple financial profit as in the case of many ‘fashionable’ breeds.
Responsible breeders strive to improve the breed standards in health and temperament and play a huge role in the prevention (and eradication) of breed-inherited disease by ensuring all the health screening checks are carried out and only the healthier dogs with solid behavioural dispositions are bred. These breeds are normally listed on the Kennel Club’s directory.
It is thanks to responsible and highly specialised breeders that we have outstanding working dogs such as guide dogs for the blind, for example, although it should be noted that some rescue dogs can make fantastic working dogs if trained correctly.
A study found that purebred dogs were calmer and had less behavioural issues than mixed-breed dogs, according to owners’ reports, but interestingly, they also rated them as ‘less trainable’ overall (14).
The ethics of purchasing a breed dog rather than adopting a shelter dog are complicated. On one hand, if you were assumed to be equally happy with either dog, one might suggest that rescuing would be the more ethical option.
On the other hand, every person, every dog and every situation is different - getting a dog from a breeder is better than getting a dog from a shelter and then giving it back to them (or a different shelter) because you cannot cope with the dog’s behaviour or health. Of course, you can never know whether you will be 'happy' with the dog either way, and purebred dogs can certainly turn out to have behavioural issues too.
Before getting a dog, you need to consider carefully the type of dog that would suit your individual situation (e.g. a puppy versus a senior dog, a dog with known versus unknown behavioural history) and what kind of problems you would be more or less prepared to deal with. Getting a dog that is unsuitable for your situation can have a huge negative impact both on your life and on the dog’s life, whether it is a breed dog, a friend’s litter, or a rescue dog.
If you can rescue (i.e. you have time, space, patience and financial resources), and you find a dog suitable dog for your situation, you have an opportunity to do something amazing and I would absolutely encourage you to do so.
The point is, however, that we shouldn’t assume that this is the right choice for anyone who wants to get a dog, and so saying 'adopt don't shop' to anyone who is remotely considering getting a god may be unhelpful.
Getting a dog in the first place isn’t the right choice for everyone! But that’s a different story.
The bottom line
Breeding can have pros and cons, both health and behaviour wise.
The choice is situation-dependent, and the blanket belief that everyone should rescue a dog and that breeders are bad is unhelpful.
People should think twice before getting a dog, whether from a breeder or not.
People who want a purebred should ensure their breeder is reputable and registered with the Kennel Club or equivalent organisation.
You can support shelters by donating to them if you cannot adopt a dog.
Check out websites like the RSPCA, Dogs Trust and Battersea rescue, even just to donate and provide financial support if you cannot rescue a dog.
Dr Miriam Carone / Pawsitive Coach, MBBS, GPST, IMDTB
References
1. Bateson, P. Inbreeding Avoidance and Incest Taboos. Stanford University Press 24–37 (2004).
2. Liu, N.-C. et al. Conformational risk factors of brachycephalic obstructive airway syndrome (BOAS) in pugs, French bulldogs, and bulldogs. PLoS ONE 12, (2017).
3. O’Neill, D. G., Darwent, E. C., Church, D. B. & Brodbelt, D. C. Demography and health of Pugs under primary veterinary care in England. Canine Genetics and Epidemiology 3, (2016).
4. Dickinson, P. J. & Bannasch, D. L. Current Understanding of the Genetics of Intervertebral Disc Degeneration. Frontiers in Veterinary Science 7, 431 (2020).
5. Abadie, J. et al. Epidemiology, Pathology, and Genetics of Histiocytic Sarcoma in the Bernese Mountain Dog Breed. Journal of Heredity 100, S19–S27 (2009).
6. Davis, B. W. & Ostrander, E. A. Domestic Dogs and Cancer Research: A Breed-Based Genomics Approach. ILAR Journal 55, 59 (2014).
7. Oberbauer, A. M., Belanger, J. M., Bellumori, T., Bannasch, D. L. & Famula, T. R. Ten inherited disorders in purebred dogs by functional breed groupings. Canine Genetics and Epidemiology 2015 2:1 2, 1–12 (2015).
8. LM, D., R, H., S, P. & CS, M. Genetic screening for PRA-associated mutations in multiple dog breeds shows that PRA is heterogeneous within and between breeds. Vet Ophthalmol 17, 126–130 (2014).
9. Lappalainen, A. K., Vaittinen, E., Junnila, J. & Laitinen-Vapaavuori, O. Intervertebral disc disease in Dachshunds radiographically screened for intervertebral disc calcifications. Acta Vet Scand 56, 89 (2014).
10. Burns, K. M. & Renda-Francis, L. Textbook for the veterinary assistant. (2014).
11. Jalongo, M. R. Pet Keeping in the Time of COVID-19: The Canine and Feline Companions of Young Children. Early Childhood Education Journal 1 (2021) doi:10.1007/S10643-021-01251-9.
12. Packer, R. M. A. et al. Pandemic Puppies: Characterising Motivations and Behaviours of UK Owners Who Purchased Puppies during the 2020 COVID-19 Pandemic. Animals 2021, Vol. 11, Page 2500 11, 2500 (2021).
13. Lucy’s Law - Gov.uk. https://www.gov.uk/government/news/lucys-law-spells-the-beginning-of-the-end-for-puppy-farming?fbclid=IwAR1Wnq14greL2mJ5w3v0YgX0GBMGvCv70KCaybiK9B79gzHml5APASFlPu8 (2021).
14. Turcsán, B., Miklósi, Á. & Kubinyi, E. Owner perceived differences between mixed-breed and purebred dogs. PLoS ONE 12, (2017).