Health
Hip Dysplasia
Golden Retrievers are susceptible to genetic disorders like hip dysplasia. Hip dysplasia is an inherited instability of the dog’s joints. This instability can be compounded by environmental factors such as over exercising and by dietary factors such as pushing rapid growth in puppies. Hip dysplasia is a multifactorial disease caused by multiple genes combined with the effects of environmental factors, its elimination is not straightforward. Currently, Australian Breeders use the ANKC’s Canine Hip and Elbow Dysplasia Scheme (CHEDs) to assess the degree of hip dysplasia a dog has. Dog’s are x-rayed after 12 months of age and the hips are scored by a specialist. The score can range from 0-53 for each hip and the lower the score the better the hip. Slow progress has been made on decreasing the prevalence of hip dysplasia. The possibility of generating breeding values for individual dogs based on multiple hip traits plus knowledge of the health of their ancestors and progeny may increase the rate of elimination of this disease and in future, genetic tests may become available to help.
Elbow Dysplasia
“Elbow dysplasia” is a term used to describe one or more inherited developmental abnormalities in a dog’s elbow joint. Generally speaking, elbow dysplasia means the development of arthritis in the elbow joint. Golden Retrievers are susceptible to elbow dysplasia and breeders screen their dogs under the CHED’s scheme. The dogs elbows are x-rayed after they are over 12 months of age and the x-rays are assessed by an expert. The score given ranges form 0-3, with 0 being normal and 3 being badly affected.
Eye Problems
There are various conditions that Goldens are susceptible to some serious and sight affecting such as, Progressive Retinal Atrophy (PRA) and Hereditary Cataracts (HC) and other conditions that don’t affect the sight such as, Multifocal Retinal Dysplasia (MRD) and Post Polar Cataract (PPC). In Australia, Breeders screen there dogs annually for these conditions.
Hereditary Heart Disease
Canine subvalvular aortic stenosis (SAS) is an abnormal, congenital heart murmur caused by subaortic stenosis (SAS) that has been detected in Goldens. There is very good evidence that it is heritable and thought to be multifactorial, so that the inheritance is complex. A dog might carry the genes for SAS, yet have no actual sign of SAS. Also, a dog might have signs of SAS and yet offspring with signs of SAS may not be seen for a couple of generations. Any animal that has SAS should not be bred, because they can definitely pass the defect on to future offspring. Puppies and dogs diagnosed with SAS can suffer from heart failure and sudden death. If a dog with SAS develops heart failure, medications can be prescribed to alleviate the clinical signs (sudden/strong lethargicism, continuous heavy panting, rise in temperature etc.) In Australia, breeders have their dogs examined by a veterinary cardiologists for heart murmurs. A dog which auscultates normally at 12 months of age is considered to be free of congenital heart disease; and a clear certificate is issued.
Ichthyosis
Golden Retrievers can be affected by excessive flaking of the skin. This is present from birth, but may be very mild, so is not always noticed. The belly may also have darkly pigmented, dry skin. It does not tend to be itchy unless there is also infection present with bacteria and yeast. Owners typically notice large flakes of skin present in the fur when brushing their dog, or on the floor in areas where they spend time. Golden Retrievers typically have a very mild form of this disease, whereas other breeds can be more badly affected. In Golden Retrievers there is a genetic test available for Ichthyosis and with responsible testing and breeding, this disease can be avoided in future generations of puppies.
Ectopic Ureter
Ectopic ureters (also called ‘wet puppy syndrome’) is known to be a hereditary problem in Golden retrievers; however the mechanism for this inheritance is not yet known. In Entlebucher Mountain dogs, ultrasound screening of healthy dogs has identified 3 ureteric subtypes (A, B & C), with ‘A’ being normal, ‘C’ being ectopic and ‘B’ intermediate. Pre-mating screening in this breed has achieved a reduction of the incidence of wet puppies from 26% to 10% over 3-4 years. The University of Cambridge is currently doing a similar study in the Golden Retriever to see if three subtypes are also present in this breed and to see if there are clinically normal dogs present within the breed with type C ureters (ectopic). This is more likely to be the case in male dogs due to their much longer urethra and consequently much higher urethral resistance. Hopefully this study will shed some light on how the condition is being transmitted in Golden Retrievers and provide a strategy for breeders to reduce its incidence.
Epilepsy
Canine Epilepsy is a chronic condition characterised by recurrent seizures. Although seizures are always abnormal events, not all seizures in dogs are caused by canine epilepsy. Canine Epilepsy is a disorder of the brain where abnormal electrical activity triggers further uncoordinated nerve transmission. This uncoordinated and haphazard nerve tissue activity scrambles messages to the muscles of your dog’s body and the coordinated use of the muscles is then inhibited. Because there are many causes of chronic recurrent seizures in dogs, canine epilepsy is not a specific disease or even a single syndrome, but rather a diverse category of disorders. Canine Epilepsy is broadly divided into idiopathic and symptomatic disorders. Idiopathic Epilepsy, also called primary epilepsy, means that there is no identifiable brain abnormality other than seizures. Symptomatic epilepsy (also called secondary epilepsy) is seizures that are the consequence of an identifiable lesion or other specific cause. Most dogs with idiopathic epilepsy suffer their first seizure between the ages of one and five years of age. A genetic basis for idiopathic epilepsy is strongly suspected in the Golden Retriever.
Cancer
When it comes to cancer in dogs, a diagnosis these days isn't as bleak as it used to be. Indeed, 50% of all canine cancers are curable, if caught early enough. The disease is mostly an affliction of old age (though, sadly, some cancers strike dogs as young as two).
It may seem like more dogs get cancer than ever before, but it’s likely because they enjoy a longer life span, thanks to vaccinations against infectious diseases like parvovirus and distemper, and new treatments for congenital, degenerative and metabolic disorders. The good news is a long-term study of Golden Retrievers is providing the necessary data to reduce in the risk of cancer in all dogs.
The high incidence of cancer in American Golden Retrievers around 60 %, appears to be a relatively recent phenomenon. Interestingly, cancer risk in Australian and European Goldens appears to be significantly lower, with a mortality figure around 40 %.
Goldens in Australia/Europe and the U.S. may look similar, but there are enough DNA differences to separate the dogs into two distinct populations corresponding to their geographic regions. Gene pools on both continents are large, so breeding between the two populations is rare.
When studied in the lab, genomic differences suggest that risk for some types of cancer is related to recent genetic mutations in North American Golden Retrievers. And this could be good news: genetic differences between North American Golden Retrievers and other Golden Retrievers may be key to understanding the etiology of canine cancer overall.
The four types of cancers common in golden retrievers – lymphoma and osteosarcoma, which are dramatically similar to the same cancers in humans, as well as hemangiosarcoma and mast cell tumours.
Health Effects of Early Neutering and Spaying
According to recent studies, early neutering and spaying may affect the risk of golden retrievers developing certain cancers and joint disorders. Current literature supports a protective effect of sex hormones against several forms of cancer. In addition, it would seem that for those cancers that are potentially promoted by sex hormones, such as mammary cancer, treatments are often successful whereas cancers that develop in the absence of sex hormones such as hemangiosarcoma or osteosarcoma are aggressive and difficult to manage or cure.
Orthopaedic Considerations:
Dogs that have been spayed or neutered at or before puberty can often be identified by their longer limbs, lighter bone structure, narrower chests and narrower skulls than intact dogs of the same breed. This differential growth frequently results in significant alterations in body proportions and particularly the lengths (and therefore weights) of certain bones relative to others. Causing the relationship between connected bones in the dog's legs to be different than what was genetically intended. This may result in an abnormal angle at the stifle and a longer (and therefore heavier) tibia placing increased stress on the cranial cruciate ligament (of the knee or stifle joint). Spayed and neutered dogs are more likely to be overweight or obese than sexually intact dogs, and this can be an additional contributing factor to orthopaedic diseases. Thus, keeping spayed/neutered dogs lean can help mitigate the increased risk of orthopaedic conditions.
A review of the literature shows that:
• Bitches spayed at 7 weeks had significantly delayed closure of growth plates as compared to those spayed at 7 months; those spayed at 7 months had significantly delayed closure of growth plates as compared to those left intact. • In a study of 1444 Golden Retrievers, bitches and dogs spayed or neutered at less than a year of age were significantly taller than those spayed or neutered after a year of age.
• Spayed and neutered dogs have a significantly higher prevalence of CCL rupture (3–7), even when controlling for body size.
• In a study of 759 male and female Golden Retrievers neutered or spayed before 6 months of age, the incidences of CCL rupture were 5 and 8 percent for males and females, respectively, compared to no CCL rupture diagnosed in intact dogs. • Dogs that were neutered at least 6 months prior to a diagnosis of hip dysplasia were 1.5 times more likely to develop hip dysplasia than sexually intact dogs.
• Spayed/neutered dogs had 3.1 times higher incidence of patellar luxation.
• Neutering Golden Retrievers before 6 months of age increased the incidence of one or more joint disorders by 4 to 5x, respectively.
Cancer Considerations - Studies have that:
• Spayed females had more than 5 times greater risk of developing cardiac hemangiosarcoma than intact bitches. Neutered males had 1.6 times higher risk than intact males had of developing cardiac hemangiosarcoma.
• Spayed females had 2.2 times increased risk for developing splenic hemangiosarcoma than intact females.
• Spayed/neutered dogs had a 2.2 times higher risk of developing bone cancer than intact dogs.
• Neutered dogs had a 2.8 times higher risk for developing prostate cancer than intact dogs.
• Neutered dogs had a 4.3 times higher risk of developing prostate carcinoma than intact dogs.
• Neutered dogs had a 3.6 higher risk for developing transitional cell carcinoma of the bladder than intact dogs, and a 3 times greater risk of developing any bladder tumour.
• Spayed/neutered dogs had more than 4 times greater risk for developing transitional cell carcinoma of the bladder than intact dogs.
• Early neutered male Golden Retrievers were 3x more likely to be diagnosed with lymphosarcoma than intact males, and late-spayed females were significantly more likely to develop hemangiosarcoma and mast cell tumour than intact females.
Other Health Considerations
• Female, and sometimes male, dogs that are spayed/neutered before puberty have an increased risk of urinary incontinence and it is more severe in bitches.
• A health survey of several thousand Golden Retrievers showed that spayed or neutered dogs were more likely to develop hypothyroidism. Neutered male and spayed female dogs had higher relative risks of developing hypothyroidism than intact females.
• Neutered females had a 22 times increased risk of developing fatal acute pancreatitis as compared to intact females. • Risk of adverse reactions to vaccines is 27 to 38% greater in neutered dogs as compared to intact.
Summary
Clearly, the veterinary practice of recommending that every dog not meant for breeding be spayed or neutered at or before the age of 6 months is not a black-and-white issue. More studies need to be undertaken to evaluate the broader health effects of spaying and neutering, and in particular to investigate non - gonadectomy alternatives to prevent procreation such as vasectomy and hysterectomy. It is clear that the sex hormones are not just important for reproduction, they also play a critical role in growth, development and long-term health. One study showed that spayed bitches had 30x higher levels of luteinizing hormone than intact bitches and given that this hormone has receptors on diverse tissues throughout the body, and that binding of LH to its receptors can induce inflammatory cascades and cell division, it is possible that the lack of a feedback loop for this hormone might contribute to some of the negative effects of early spaying and neutering, at least in females.
In consideration of the evidence presented here, it is apparent that early spay and neutering presents significant risks to dogs. This is particularly true given that the procedure is not required to prevent procreation, the predominant reason for which this procedure is considered. Therefore, before performing, it is important that we assess each dog and its living situation individually, weighing the risks and benefits of spaying and neutering. It is also critical that the pros and cons of the procedures and their alternatives are discussed. There is no single solution that fits every dog.
Written by the National Golden Retriver Council