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                                  ROUGH & SMOOTH COLLIES AND GENETIC HEALTH



Although many think that purebred dogs are less healthy than the mixed breed, this is a myth.  Mixed breed dogs can and do inherit a vast array of genetic disorders, that statistically are shown to be no less common to their mixed breed heritage as it may be in purebred dogs. The propogation of such a myth has roots in extreme animal rights activism and is not based on true scientific fact.  This "myth" has been sold to/ bought by many in the general public and even to some veterinarians, but it is not fact.  Having said that, many experienced breeders practice what is known as linebreeding ( the mating of relatives) in order to establish certain type, temperament and characteristics into a family of dogs that are desirable and sought after.   With that in mind, this close linebreeding can also establish things that are definitely NOT sought after, such as poor conformation, poor temperament, structures and health related issues if proper due diligence has not been practiced by a breeder.  If a breeder is not conscientious or ethical, the end result can be a mess and those who suffer are the dogs themselves.  However, as with any natural genetically based process, even with the utmost due diligence, Mother Nature can and does throw curve balls. Even the most conscientious of breeders may deal with totally unexpected illnesses in their dogs as a result and there is certainly no shame or blame to cast in such circumstances.  It is in how a breeder handles the unexpected that sets apart what we deem to be a good ethical breeder from one that is not.  This is yet another very good reason as to why formal health guarantees provided by a breeder, become so very important to any prospective dog owner. At Davenloch Collies, we practice three forms of selective breeding, outcrossing, linebreeding & inbreeding in our pursuit of the perfect Collie. At this point, it should be stated that we do not breed to win a ribbon at a dog show at all costs. We breed first and foremost for the Collie as a breed, not for the show ring.  Yes we like showing but the wellbeing of the breed itself is considered above all else.  The breeding method chosen at a particular time depends on the intended result(s) of a breeding, and ALWAYS in the best interests of our Collies - ALWAYS.  Linebreeding and inbreeding methods are common and widely used tools in animal husbandry.  When utilized responsibly by truly ethical breeders, this WOULD NOT intentionally and knowingly produce deformed or sick progeny in such practice. A breeder's practice of true ethics, or lack thereof, will determine the end result.


At Davenloch we take a systematic. methodical approach towards reducing and eliminating genetic weaknesses/defects in the Collie while addressing the entire dog.  Our experience has shown us that although there are indeed breeders out there who promote health and genetic testing in their  breeding animals, some (NOT ALL) but some such breeders focus and concentrate on one aspect of the entire dog based primarily on genetic marker testing and other aspects of the Collie at the very most are given secondary consideration, if given consideration at all. The same point could be stated about concentrating too heavily on type, or temperament or soundness of body.  Do not take what we are saying here incorrectly! Health is indeed a key cornerstone of any breed.  Without a healthy animal, they can perhaps be the most esthetically beautiful Collie known the man, but what good is beauty if the dog is riddled with illness?  Not much good at all.  Here at Davenloch, we base our breeding program on FOUR KEY AND EQUAL CORNERSTONES AS FOLLOWS:  HEALTH, TYPE, TEMPERAMENT & SOUNDNESS.  It is our belief and conviction that if any one of these cornerstones is unbalanced or missing, the Collie is NOT done justice and the breed suffers as a result.  You can not consistently promote one cornerstone over another and expect to truly be a steward and guardian of any breed.  YES HEALTH TRULY MATTERS, BUT SO DOES TRUE BREED TYPE, TRUE BREED TEMPERAMENT, AND SO DOES A BODY UNDER THE COLLIE THAT IS CAPABLE OF DOING THE JOB THE BREED IS INTENDED FOR!  We are so very careful to address each and every cornerstone in our selective breeding practices and although this may not be the easiest and fastest route, this is the route we choose as breeders as far as our Collies are concerned. 


The intent of this section is to share an understanding of certain health issues in the Collie, and state that there are very respected and dedicated breeders who take the health of their breed as seriously as they do it's outward beauty, temperament and functional structure.  We hope to dispel a few myths that do float around, however this is not intended to be a comprehensive, detailed overview of all health issues in the Collie.   No reputable/ethical breeder who truly has the Collie at heart would set out to intentionally breed life threatening genetic illnesses into their dogs.   With that in mind, we at Davenloch choose to be as informed as we can be on these issues, so as to breed the healthiest most beautiful Collies we possibly can, that act like a Collie should, loyal, loving, trusting and intelligent. At Davenloch, we test our breeding dogs for either the effects of or presence of various genetic issues, including Collie Eye Anamoly, Mutant Drug Resistant Gene (MDR1), Degenerative Myelopathy. and DMS (Dermatomyositis Risk Assessment). 


The responsibility of any truly ethical breeder is to ensure that when they engage in selective breeding practices, they are MORE THAN diligent towards investigating in depth, the bloodlines, pedigrees, individual dogs and their genetics,  they may be or wish to be utilizing in a current breeding program.  


The Collie of today, is a breed that when compared to many other breeds is relatively free of some very serious health issues.   Having said that, this can be no reason to take a complacent approach towards the health of the breed.   It must be acknowledged that there are issues that do exist within the Collie  requiring very diligent and stringent measures. We often hear a term floating around out there used by breeders who do not health test their dogs, " I dont have that in my line, or I have never had that issue" Well fair enough we say.  Yet, when you do not test, you have no idea whatsoever, what maybe lurking and ready to rear its ugly head at any given time. For us, this is not a sensible or responsible approach to guardianship of the breed. Health testing for us, is an essential tool and guide that allows us to make the best decisions possible when we selectively breed dogs.  Eradicating such health issues and/or reducing the likelihood of such issues expressing themselves in the collie of today, while not losing the outstanding advancement of the Collie as the magnificent wonderfully tempered animal we look at today, should in our opinion be the goal of a reputable breeder.  We carefully weigh out the goals of any breeding we do here, with health as a key priority and cornerstone each and every time.   This is an issue that is debated extensively amongst many breeders of not only Collies but most other breeds.


By far the most common and talked about issue in the Collie today is what is known as Collie Eye Anomaly (CEA) .   This genetic issue expresses itself in a myriad of ways ranging from a simple lack of pigment in the back or fundi of the eye, to retinal detachment and blindness, and other varying forms in between.   It is estimated that approximately 90 percent or more of Collies in the current gene pool, either exhibit some form of CEA and if not, at least carry the gene(s) responsible for CEA. To any potential owner of a collie, this might seem to be an insurmountable obstacle, and cause some to shy away from such a lovely breed of dog.


A reputable Collie breeder will perform formal eye exams on all their puppies and breeding stock.   Selection for future breeding stock is made on the individual dogs who, as one selection point, hopefully are free of the genetic predisposition of this issue, and if that is not possible,  mildly affected individuals are utilized in breeding only under experienced and supervised conditions.   Of course it would be the ultimate ideal and goal to not utilize any animal that is affected with CEA in any way, whether that be as a carrier only or having the outward physical proof of CEA's presence. An ultimate goal as well as the ideal, of course, but at what other cost, the eradication of a majority of the Collie gene pool, with all the incredible positives that they also come with?  One would hope not, as this would eliminate so much of an already fairly limited gene pool available to breeders today.  CEA in the form of basic Choroidal Hypoplasia does not in any way affect the sight of the dog and does not worsen with the age of the dog.   This fact should be communicated to those who have an interest in the Collie but may be weary due to this much talked about issue. Of course it would be ideal to use only non-affected dogs, but we do not believe that the cost to the Collie in the end justifies taking such measures.   With the goal of eventual eradication of this issue in mind, we forge on and strive to do the absolute best for the Collie with what we now have to work with.     The use of dogs that may exhibit more severe forms of CEA in a breeding program is a topic of much debate amongst Collie fanciers.   In the end, it is the choice of the individual breeder, and any potential puppy buyer should investigate this with any breeder that they approach respecting a puppy. At Davenloch, we deal with the issue of Collie Eye Anamoly very very juduciously.  We strive to introduce normal eyed breeding stock into our program as we move towards eventual eradication of CEA while maintaining the beautiful faces, expressions, health, temperament, balance & soundness that Davenloch Collies are known for.


There are forms of CEA that could in fact affect the sight of the dog such as large colobomas (pits at or near the optic nerve head).   A proper thorough formal eye exam will indicate just what may be going on and should be a requirement for all dogs used in breeding and as a demonstration to a potential new Collie owner that such due diligence has taken place.


Other eye issues exist in the the form of cataracts and what is known as Progressive Retinal Atrophy (PRA).   These issues are NOT related to the more common form of eye defect known as CEA, but are another form of eye defect that has expressed itself in certain lines of Collies.   PRA is a severe defect that leads to complete blindness and is proven to be a recessive gene meaning that if a dog develops PRA, both parents contributed their half to cause the expression of the defect.   At present is believed to be far less common than CEA.   CEA itself is also a recessive gene issue, but the expression of the degrees of defect for CEA takes on a much broader form than do the stand alone eye defects that are not related to CEA. Davenloch Collies provides a written health guarantee for both juvenile cataracts and PRA.



                                                         MULTI DRUG SENSITIVITY IN COLLIES

      For information related to multi drug sensitivity in collies, please click on the link below. Within this link, is a list of problem drugs, available in the menu on the left hadn side of the screen.








In the event that testing for the mutant gene responsible for this drug sensitivity has not been performed, we advise to assume that your collie does have the mutant gene, and to ADVISE YOUR VETERINARIAN TO NOT PRESCRIBE OR ADMINISTER ANY DRUG THAT COULD CAUSE A SEVERE LIFE THREATENING REACTION IN YOUR COLLIE!   A list of such drugs is available in the link above but please be aware that these may not be   complete lists, so all the more a detailed discussion with your veterinarian is vital! A collie will in no way exhibit that this mutant gene exists except for when such drugs are administered.   With this issue other than from the direct administering of the drugs, a collie would for all intents and purposes look and act perfectly normal.


Further to this drug sensitivity issue, there is now debate amongst dog fanciers that even with MDR1 gene testing available, these tests may not be conclusive as to whether or not your dog will have a reaction to certain drugs, even if they test as Normal/Normal.   All the more Davenloch advises to assume your dog would react to certain drugs regardless of Normal/Normal MDR1 test results, and to avoid such drugs for the health and wellbeing of your collie.   We are in no way insinuating that MDR1 tests are not valid.   We are merely stating that there is debate amongst dog fanciers as to the source or sources for adverse drug reactions, and in light if this, it is better to be safe than sorry.





                                                           DEGENERATIVE MYELOPATHY (DM)



This disease was once thought to NOT impact Rough and Smooth Collies.  The fact is that it does exist in them.  Davenloch Collies performs genetic DNA tests for Degenerative Myelopathy on all breeding stock through the Orthopedic Foundation For Animals (OFA).  We are able to provide such results on all individual dogs used for breeding either by OFA certification or as a result of testing of parentage of resultant puppies themselves.   The genetic marker identified through testing, at this point, is only an indicator of a certain animal having a lesser or greater predisposition towards developing this disease.  Because there are still numerous other possible causitive factors , dogs tested for this disease can only be rated as either

A) CLEAR,  B) CARRIER (one copy of the gene identified) or C) AT RISK ( two copies of the gene identified) - As mentioned above, test results only indicate whether or not a certain dog has a lesser or greater predisposition of developing this crippling and life ending disease, but can not at this point, with 100% certainty, state whether or not a certain dog will or will not develop Degenerative Myelopathy.  That said, Davenloch Collies, chooses to NEVER breed a dog identified as a CARRIER to another dog identified as a CARRIER which could easily produce a resultant puppy that carries two copies of the identified gene rather than just one or none at all.  This totally eliminates the possibility of us here at Davenloch,  ever producing a Collie deemed to be AT RISK ( having a FAR greater likelihood of developing the disease ) than those tested and deemed to be only a CARRIER or CLEAR. We are following very closely, the developments in the science surrounding this extremely important issue for our breed , and we are hoping for an even more concrete test in the near future. In the interim, we choose to eliminate the propogation of the gene currently identified, through our selective breeding practices.  Because this thus far has been a disease of older dogs, usually age 8 or more, many Collies who have been afflicated by it, were thought to have developed other conditions like arthritis.  It has now been learned and proven concretely through necropsy, that Collies have died as a result of this disease.  Furthermore, genetic testing results show that out of the small number of Collies tested so far to date, that nearly 42% of the dogs tested were either CARRIERS or AT RISK according to OFA statistics.  It is our opinion here at Davenloch that should breeders not address this issue with the testing that is available today, the Collie breed could be severely compromised with this disease like many others have been already.  Below is a link to more information on this issue.  We believe such genetic testing is a must!









                                                       DERMATOMYOSITIS (DMS)


For information related to this serious health issue in the collie, please see the link below.  We now have a risk assessment test available, that Davenloch Collies utilizes on a regular basis on ALL of our breeding stock, to ensure any and all dogs produced through our breeding program are at the lowest risk levels possible of ever developing this horrendous and life threatening disease.  This is for us, one of the most, if not THE most important risk assessment tool available to Collie breeders today!








Please keep in mind that this is not a complete list of all health issues related to the collie, as you can well imagine, just as in humans, how long a list could be. We in no way profess to be veterinarians, and the information and links provided on our website are provided as one form of access to the vast array of information on the subject through the web, as well as our personal opinions.   We can't   assume any responsibility or liability whatsoever as to the validity or accuracy of the content of the sites linked to our website, but believe that creating awareness and thought around these important issues is vital to the future of the collie.   We have touched on a few key health issues, that appear today to be at the forefront of research, detection and treatment for the betterment of the breed and we hope that you have found this informative.  






Davenloch Collies is a member in good standing with this extremely important organization and we fully support their goals and mission as stated on their website and included below, towards the health and well being of all Collies.



  • To foster and promote the public’s knowledge and appreciation of dogs in general and collies in particular;

  • To further understanding of the diseases, defects, injuries and other ailments that afflict dogs in general and collies in particular;

  • To support and promote the study of and research on the history, character, varieties, breeding genetics and particular health problems of collies;

  • To establish a national data base of resource materials about collies;

  • To produce, publish & distribute to the general public educational materials about the proper care, treatment, breeding, health, development & training of collies


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