The following information is my personal point of view, either from experience or knowledge compiled from other breeders or doctors.
Collie eye anomaly (CEA) has long been a problem in collies. Once it was recognized, most breeders went to work on decreasing the severity of the problem, but not decreasing the number of collies with the problem. Consequently, we still have about 70% of collies affected, but most have very little vision impairment. They have small blind spots (or areas of reduced vision) due to the lack of development of the choroid which is the vascular layer of the back of the eye. Usually both eyes don't hit a blind spot at the same time, so the dog can always see. This problem doesn't get worse with age. If a pup has a coloboma, that could get worse with age. If that coloboma is near the optic nerve, that pup could go blind someday. If eye checks aren't done on all litters that have potentially affected pups, the severity could get worse again. Pups must be checked prior to eight weeks of age. After that age, a very mildly affected pup could test normal because what the doctor is looking for can be covered over with pigment making it impossible to see. If and when this pup is bred, it will produce as an affected dog, which it is. The owner may be baffled as to why. If you are buying a pup with a normal eye check and the breeder tells you that both parents are affected, don't believe it. It's not possible to get normal eyes from two affected parents. The eye check was most probably wrong. It is a recessive gene, taking two affected genes to make an affected eye. One affected gene makes a normal eye, but a carrier. Since there are only two genes involved (one from each parent), and both parents are affected (two affected genes each), where could the normal gene come from. It's pure logic. Here's what to expect: If breeding two affected parents, all pups will be affected, for sure. Breeding one affected to one carrier produces half affected and half carriers. Two normal eye carriers will produce 25% affected, 50% carriers, and 25% noncarriers. If one parent is affected and the other a noncarrier, all pups will be normal, but carriers. Breeding a carrier to a noncarrier produces half carriers and half noncarriers. Finally, if both parents are noncarriers, all pups will be noncarriers. These are averages. Actual percentages may vary.
I will explain this problemed disease as I have experienced it and from the research I've done on it. Early research by dermatologists had proven to them that dermatomyositis, from here on referred to as DM, was a dominant gene. When they bred an affected collie to an unaffected dog of a breed known not to have DM, about half the pups had it. So, it made it clear there are no carriers, the dog either has it or not. A collie with 2 affected genes would produce a whole litter of affected pups. It is a far worse problem than CEA as it deals directly with the dogs health. As the name implies, it deals with the skin (derma) and the muscles (myo). If all collies that had the disease showed it, it wouldn't be such a problem. But, even though it is a dominant gene, the dog may show no symptoms at all. Hence the term "variable expressivity". As I said, it is a dominant gene. If a collie has one gene with DM, the collie has DM. Dermatologists now believe that at least 70% of all collies have DM. New research is being done now, but it's to try and find a genetic marker in the DNA. More on this later.
The skin lesions normally only occur between the ages of five to eighteen months of age. They may go on longer in severe cases. These lesions come and go on a cycle of about monthly. Many vets don't know about DM yet and may think it's a staph infection and treat for that. They believe they're successful because the lesions go away. When they come back, the vet figures he didn't treat it long or hard enough and repeats the treatment with higher doses for a longer duration. Of course it goes away again, but will probably come back. It would do this untreated. It goes on for a few months, being a little less each time, until it no longer occurs anymore. In very mild cases, only a lesion or two may be seen making the breeder think it was just an injury, or may not even notice them at all. Then, as mentioned earlier, the dog may never have any lesions at all, but still have the disease. One reason why no lesions occur could be because the dog may have such a good immune system that it suppresses them. One research project came up with another possible reason. They found that in a line of collies that has had DM for several generations, the lesions rarely, if ever, occur, leading the breeder to think all is ok, but the myositis is more severe as the dog ages. The lesions are worse when newly introduced into a line, but the myositis is minimal. If this is true, it explains why when a breeder with collies clear of the disease breeds out to a stud dog that never showed the disease, but has it, some of the pups have lesions and both breeders are scratching their heads blaming each other. With a disease that behaves like this, it's very difficult to defeat it. I'll get back to this later as well.
The appearance of the lesions is different from anything else that may occur at a young age. It can resemble lupus, but that occurs at older ages. The lesions first appear as tiny raised spots of skin. In a couple of days it will get a scab on it. A few days later, the scab falls off, usually taking a few hairs with it as any scab would do. In no time the skin looks fine again in that spot and the hair generally grows back. In severe cases, these lesions are deeper, but never pussy. It never looks like demodex, which is just bald spots due to infected hair follicles. I've read other sites about DM where they state that it can resemble demodex, in my experience, it never does. The lesions are distinctly different. Only the extremities are affected, usually starting with the muzzle in very mild cases, moving up between the eyes onto the back skull in more moderate cases. It's normal for crusts to occur on the ear tips and tail tip. These are crusts, not lesions. They crumble if you rub them between your fingers. Again, a very distinct symptom of DM. The lower legs get involved in more severe cases. Usually these lesions just happen. But, there are cases, as in one of my litters, where the lesions are stress or injury induced. Had the dog not been stressed, it may never had showed symptoms. All affected collies in that litter were stress induced. One male had symptoms because bitches were in season. His sister was induced from her own season. Another dog, a severe case, was injury induced at nine months old. His lesions went on for several months involving his whole head and all legs. When he reached 2 1/2 years old, you couldn't tell he ever had anything wrong. They seem to outgrow the skin problem part of the disease by 2 years old.
The worst part of the disease is the muscle atrophy that may occur as the dog ages. It usually affects the head muscles the most. One indication of muscle atrophy is food particles in the water bowl. This doesn't mean that only DM dogs have dirty water bowls. A nonaffected dog could get food particles in it's water bowl, too. But, it is an indication. So far, it isn't common to have severe muscle atrophy to the point of having to put the dog down, but I guess it could happen sometimes.
The only way that DM can be confirmed, is through a biopsy of a lesion to confirm that type of lesion and a biopsy of a muscle to confirm myositis. The most common muscles to biopsy are the temporal muscles or a muscle in the shoulder. Conformation of just one without the other doesn't confirm DM. Myositis alone can be there for other reasons and so can't lesions. But, as mentioned earlier, the lesions are a little different than most.
Now, here's my conclusions after a few years of thought and research. As stated earlier, one research effort showed that muscle deterioration was worse in lines that had several generations of DM inbred, but the skin problems were minimal, whereas when first introduced into a line the skin problems are worse, but with little muscle deterioration. Well, I do believe it's worse in some lines than others as far as muscle atrophy goes, but I think all collies are predisposed to it. Here's why. Only two other breeds are known to have the same type of DM symptoms. Remember I said same type, some people think it's in more breeds. These breeds are Australian Cattle Dogs and Shelties, both of which have been made up with some collie in their backgrounds. So, it only figures that it's been in collies for a very, very long time to have passed it on to these other breeds. With no effort to breed it out after all these decades, I would think that virtually all collies have it. To my way of thinking, the degree of affectedness is similar to Collie Eye Anomolly in that some dogs are more affected than others due to a coding on the gene. In those highly affected dogs, you see more muscle degradation. This results in a head that feels boney rather than well muscled. As far as the skin part of the disease goes, I believe that dogs with stronger immune systems show no skin problems because the immune system overcomes it while dogs with weaker immune systems get lesions. It seems common that dogs with DM lesions also have demodex which is a clear indication of a weak immune system. Also, in the case of injury or stress induced lesions, the dogs immune system is lowered due to the stress or injury which allows the lesions to begin. As the dog grows older, it's immune system gets stronger and the lesions go away, never to be seen again. So what does all this mean? If I'm right about this, it means a genetic marker will never be found because they'll never find a collie clear of the disease to compare DNA to. What can breeders do about it? First off, they should stop waiting for research discoveries and not breed any collies that ever had lesions or have poor head muscles. Whether I'm right or wrong, it's the logical thing to do anyway. Breeders did lessen the severity of Collie Eye Anomoly by not breeding the bad ones. The same can be done with DM. The bad ones are the ones with poor muscling on the heads. As far as the lesions go, they shouldn't be bred either because it shows a low immune system. With good breeding practices we can reduce the severity to the point where it doesn't show, but if all collies have it, it can never really be eliminated, only controlled.
I did a test breeding of a bitch with DM lesions to Renny, whom I believe has a very strong immune system. I kept tract of all the pups until their first birthday. None of the pups ever had any lesions. This breeding indicated to me that the bitch had a poor immune system and bred to Renny, the pups immune system was stronger than hers and therefore showed no symptoms. The other thing I've noticed in other litters and dogs I've acquired is that all the pups that had lesions or crusts weren't dominant dogs. They were more submissive in nature. Submissive pups are more stressed in everyday living in a pack life like I have here. That can lower their immune systems which will allow DM lesions and/or demodex to result. But always as the dog matures, the immune system gets stronger and the lesions, like demodex, goes away and never returns.
If you are buying an adult or are looking at a dog to use as stud, go over the head carefully. If it feels more boney than what should be normal, stay away. Remember, the first muscles to be affected are in the head, so feel the head carefully. This doesn't mean that a dog with good muscling doesn't have DM, but if it has poor muscling, it's more severe. Check the heads on the parents of the puppy you want to buy. If there are other close relatives there, check them too. You want to feel a smooth head with no protruding bones. The muscles on either side of the occipital bone should be strong. The occipital bone shouldn't stick up above them.
Demodectic mange is caused by an over population of the demodex mite. This mite is supposed to be on the dog. In fact, probably all animals and people too, have these mites. They are there to keep the skin clean. They eat the dead skin and other stuff that gets there. Sometimes, a puppy's immune system isn't as good as it should be and they get mange. The most common times for this to happen is when teething or going through puberty. The later most pet buyers don't see because they had their dog spayed or neutered. Sometimes a pups immune system is slow to get started and they get some localized mange, usually on the face. In the majority of cases, their immune system recognizes this, kicks in, and takes care of the problem without treatment. This type of mange is not considered a problem. If the mange doesn't clear up and spreads, it becomes generalized and needs treatment. The standard treatment has been dipping. Short haired dogs can be dipped as is, but long haired dogs should be shaved first to allow good penetration of the dip. With a lot of patients and work, you may be able to dip without shaving. A dip containing amatraz is what's normally used. The dog needs to be dipped every week for 6 weeks. A scraping should be made at that point, hopefully finding no mites. It's virtually impossible to kill them all and you don't really want to. As I said earlier, these mites are part of normal healthy skin and should be there, but in lower numbers. Hopefully, the dog will have built up a better immunity to the mites and not get mange again. In some cases, the immune system is impaired and mange will reoccur. Another method of treatment is a monthly dose of heartworm preventive everyday for at least two months. This can obviously be very expensive. In collies, Interceptor is used because of the sensitivity fear of ivermectin in Heartguard. However, new studies have shown that collies sensitive to invermectin are also sensitive to melbinicin which is used in Interceptor. So, I'd say both of these products are risky in collies when used at these high doses. My prefered treatment would be to dip. Plus, dipping works much quicker, not to mention it's so much cheaper.
I've recently discovered that the canine herpes virus could possibly prevent a mother from passing immunity to the mites to her pups. Early in 2002, I had two very healthy litters born. Both mother's had picked up herpes at a dog show three months prior to being bred. Normally, that causes no problems. Herpes is widespread because it's an airborne disease and many showdogs will get it at some point. I had a total of 19 puppies in the two litters. All 19 pups got generalized demodex mange at approximately 5 months old. When I tried to find a common link, the only thing that came up was the herpes virus. I contacted an immune/blood specialist and found out that the virus could indeed prevent the mothers from passing immunities to their pups. Once treated, none of these pups had a reoccurance, indicating that they had built an immunity to the mite from having the mange. I'm currently doing a couple of test breedings to prove a few things one way or another. One thing is, it's not known whether the mothers are permanently incapable of passing immunities or not, so another breeding has to be done to find out. The other thing is, will these puppies be ok to breed whereas they built an immunity to the mites by having mange, will they be able to pass that immunity to their pups and have no future problems. This apparently isn't a genetic problem whereas there's been no mange at all in past generations. So, test breedings are in order to find out. My personal research should be done by mid 2004. I will post my findings here. This could set a new light on some cases.
A would have to say that bloat is probably the worst of all problems a dog could have. Bloat can and does kill. Although only a small percentage of collies actually bloat, I think the numbers are increasing. There is currently some research going on studying the problem in collies, as well as other breeds. What actually happens can be one of two things, or both. Sometimes a collie will bloat because of gases building up in the stomach and the sphincter muscle (which is between the stomach and esophagus) won't open to let it out. In other words, the dog can't burp. The dog can be in a lot of pain. Normally, a small tube can be inserted down the esophagus and into the stomach to release pressure. But, in many cases, this goes one step further and the stomach actually turns over, called torsioning, pinching off both the esophagus and small intestine so nothing can leave the stomach. Obviously, immediate attention is necessary. If the dog makes it to the vet, an operation can be done rather quickly to turn the stomach back around. The stomach is usually tacked in some way to prevent this from happening again. I've heard of cases of collies torsioning with empty stomachs.
I believe bloat is hereditary in most cases. It seems to follow certain genetic lines. If you suspect your collie comes from one of those susceptable lines, talk with the breeder for advice on trying to prevent it from happening. The normal routine is to feed a few small meals each day and have the dog rest awhile after each meal. That may work in some cases, but what about the dogs that torsion on an empty stomach? I don't have the answer. Some people believe that soy in some cheaper dog foods can cause it to happen. I, so far, have never experienced bloat in my collies and hope I never do. My guys seem to have no problem burping after eating, even in my face sometimes. My advice when buying a puppy is to ask the breeder about it. If that breeder has experienced bloat in their line, well what are you going to do?
Coccidiosis is caused by the parasite coccidia. It's an intestinal parasite and normally only bothers young puppies. As the pups grow up, they build an immunity to the parasite and therefore, live with it without problem throughout life. There are some rare times, when an adult dog may be unduly stressed, that it causes minor problems. The symptoms in puppies are bloody diarrhea, dehydration, and eventually lack of energy. Normally, pups at 6 weeks of age or more can handle it ok and pull through without treatment. However, there are some pups and litters that don't and they do need help. If it gets to the point where all you see is a bloody mucusy discharge of a clear color, you need to treat it. Odds are the pup is looking quite skinny and is lacking energy at this point. There is more than one strain of coccidia, some harder to kill than others, and some affect the pups as early as 3 1/2 weeks of age. Others start causing problems at 5 1/2 to 6 weeks of age.
How do they get coccidia? Well, the myth that pups get it from dirty conditions is very untrue. It can be acquired from the ground, eating another dogs feces, and it now seems to be true that pups can get it from their mothers right after birth from scrambling around the rectal area looking for milk or trying to keep warm. Their mothers are stressed from birth and the coccidia are probably more active at this point. Coccidia do live in the ground. If other animals have been raised on that ground, odds are it's there. Once it's there, it's virtually impossible to get rid of it, so you live with it. Neither heat nor freezing cold will get rid of it.
Treating affected pups is quite easy. The two best methods are using Albon or Corid. Albon takes longer to stop the diarrhea and the treatment runs to two weeks or more. It may be more affective in the long run because the pups are older when the treatment is done and should have enough immunity to it to stay healthy. Corid, on the other hand, is a liquid (that doesn't taste very good) that you give by syringe orally. It gets the problem under control in 3 or 4 days and the standard treatment is for 5 days at 1/2 cc per pound of puppy. If you have a more durable strain of coccidea, you may need to treat for 10 days. Another method of using Corrid is to put 30 cc per gallon of water and just let the pups drink that. That method is done before symptoms start to prevent them. The problem with that method is, the pups hate the taste and may not drink enough. Neither of these products actually kills the parasite. Like I said, it's virtually impossible to get rid of it. What these products do is interrupt the breeding cycle of the coccidia, which reduces it's numbers temporarily. The parasite is still around, however, so the numbers build up again later. By the time that happens, the pups are better immune to it and problems are minimal.
Overall, coccidea is very common amongst farm animals and dog breeders. It's not something to worry about. In fact, it could be a good thing in an odd sort of way. The pups are exposed to it before they're sold and leave with a good immunity building against it. Pups that aren't exposed to it have no immunity. If at some point in their lives they do get exposed to it, they'll probably go through some of the symptoms until their immunity builds. I feel that the more things the pup has immunity to, the better. Most all of these things are part of life.
Remember, everything I've written here is "my opinion" based on experience, research, or conversations with other people, breeders and veterinarians.