Fading Puppy Syndrome – One Possible Cause: Until relatively recently, canine herpes seemed to be a problem only in the whelping boxes maintained by rank novices in breeding dogs. Experienced breeders could control it, prevent the effects. But it appears that perhaps a different strain of virus may be running rampant and causing more and different problems for breeders. From the website www.canineherpes.com , comes the comment, “Canine herpes virus has been largely forgotten for many years, due in part to the difficulty in making a definitive diagnosis. However, it is becoming increasingly clear that the virus causes many more problems than was first thought.” They were speaking mostly of the fading-puppy syndrome where entire litters die off, one pup at a time, in the course of a day or two at most.
Herpes is caused by a virus. Demodectic mange is caused by the action of a parasitic mite on the dog that has a weak immune system. Alike as night and day, you might think, but there are one or two similarities: some dogs are more resistant to such attacks than others, and the causative or triggering culprits are almost everywhere. A close similarity in control and resistance is in the response to other antigens, such as hookworm, coccidiosis, and even parvo. None of these is an automatic death sentence if the dog is an adult or adolescent, and is otherwise healthy. The very young and the very old are less able to fight off new microbial or parasitic attacks. The more such stresses are put on these individuals, the worse the prognosis. I have seen puppies die of combinations like coccidiosis and hook, when they would have survived if only one of those had been present. I have seen adults exposed to parvo for the first time and come through the ordeal just fine. But combine the threats, or aim them at the age extremes, and mortality rates become very high.
What I meant by the omnipresence of antigens is that Demodex mites, for example can be found on perhaps well over 90% of dogs and a big percentage of humans. (One researcher said, This disease can literally be carried home on your clothing.) It’s like dust or pollen: it’s everywhere. But with an immune system not up to par, and a combination of stress factors, and you have dangerous, even fatal consequences. I once bought a bitch puppy for my mother. The pup developed severe generalized demodecosis so bad that all attempts at control failed, and she had to be euthanized. Estrus is by far the most stressful trigger for demodicosis. Herpes virus, though an entirely different organism, also exists on or in nearly all animals, including probably a transient and harmless guest on humans. However, we therefore could transmit the virus to our dogs. Virus particles do not live forever in non-nutrient (host) environments, but long enough to be carried to the ultimate host on clothing, by sneezes, etc. It is the immune-challenged weakened pup that would fall to its onslaught. One difference between Demodex and Herpes is that the mite is alive and active, though ineffective against a healthy dog; herpes virus microbes enter a dormant state and are awakened by various stresses. Merial says, Most animals have already been exposed. Although it can be spread at mating, it is much more likely to be spread by simple contact.
According to an Australian website, and an article by Dr. Mary Wakefield, Puppies die of Herpes only so long as they are unable to mount a fever response, or have the lower body temperature of neonates. After 3 weeks of age puppies can raise their body temperatures high enough to resist the overwhelming infection which results in death. The treatment for Herpes in young puppies with the appropriate signs is elevation of the body temperature. Check with your veterinarian if you think this may be the problem in your litter under three weeks of age. The problem with that advice is that by the time one has a clue to the presence of the disease (the first dead or dying puppy), it is too late. The others are likely to have been just as chilled during a period of exposure to the virus. And in weakened pups, the virus can replicate like wildfire.
Unfortunately, the Wakefield piece, while very helpful overall, has some minor problems. For example, she states, The best way of preventing newborn puppies from acquiring the disease is to quarantine them and their dam from 3 weeks prior to birth and 3 weeks after whelping. If the virus is everywhere, as it almost always is, that is no solution. There are only two ways (1.5, really) that I have confidence in to prevent neonatal deaths from herpes: elevated ambient temperature during the first three weeks, and the possibility of the Merial vaccine (but still, I would not lower the thermostat!). Wakefield says, Herpes infection of the dam which does not result in abortion may result in low birth weight, weak, or stillborn puppies. And, she says that titers show herpes activity in 80% of bitches who had lost their litters, even though there was no bacterial blame. Wakefield advocates isolation, but I believe that’s a lost cause; Merial states, The virus does not come from bad kennels; it is already everywhere! Since immunity is very short-lived, contracting the problem again and again is to be expected. Dogs have fluctuating titer levels all the time, some of it due to new exposures, some due to stress-released previously dormant particles.
HERPES: There are many organisms in the virus family called herpes, the most common in dogs being the puppy killer at ages of around two weeks or less. Herpes seems to be present in most dogs most of the time, but some pups are more susceptible or under more stress, which lowers their resistance. New puppies that are not given adequate drying, heat, and nursing opportunity (internal warming) right after delivery are most at risk. Once the disease has been noticed in a litter, few survive. Prevention is the only remedy in nearly all cases. It is practically unstoppable once noticed.
NEONATAL DEATHS AND HERPES VIREMIA: This syndrome, caused by a herpes virus, is a major cause of death in pups between five days and three weeks, and may take two weeks to spread through the litter. Herpes actually refers to a class of several viruses, so you may encounter the word used in the context of a human disease, or a disease in other animals. One of this class will not produce the same disease as will another. With this viremia, death from kidney and liver failure usually occurs within eighteen hours; symptoms include constant crying, shallow and rapid breathing, loss of appetite and coordination, and a soft, yellowish green stool with no particular odor. The stool symptom can be easily missed if the bitch is cleaning her pups to make them defecate.
TREATMENT includes elevating the environmental temperature, thus creating a sort of artificial fever since fever is one of nature’s ways of fighting virus organisms. Close to one hundred degrees F (38 C) for the first three or more hours post-parturition is a recommended ambient temperature, followed by 90 to 95 degrees for another 24 hours. Some people who have worries about the drying-out effect of such high temperatures frequently give the pups glucose solution and formula to prevent dehydration, but I have had hundreds of puppies born to my bitches without that. I just make sure that the floor is warm or insulated, and the heat lamp, heating pad, or low-hanging light bulb is on when the dam is going out to potty for the first weeks. Herpes thrives even as high as between 91 and 98.6 degrees F (33 to 37 degrees C), and chilled pups are especially susceptible. At 100 or 101 degrees the virus stops replicating, so the object is to get the pup’s body temperature up to that which is considered normal in the adult, about 102 degrees. After three weeks of age, the pup’s body temperature is usually high enough to prevent herpes growth, and by then they have developed the shiver reflex, which is another heat-regulating mechanism. However, because damage to kidneys may not produce symptoms until as late as ten months of age, perhaps the surviving pups (in a litter with pups known to be dying of hypothermia -exacerbated herpes) that show the crying symptom associated with hemorrhage and necrosis should be euthanized right away. Ask your veterinarian about treatment with a preparation, Vira A, designed for human herpes encephalitis, or he may have more recent advances. But I have not seen any good results from any kind of treatment. A few pups will survive now and then, but regardless of treatment (other than elevated temperature).
This virus can remain latent for many months and be reactivated by stress or an immunosuppressive agent such as a shot of cortisone or similar steroid. Thus, pups that contract a marginal infection but not enough to be fatal, might still have their immune system weakened, or else harbor the inactive virus. Pups seem to get the virus through the saliva of their infected dam, though a few may contract it in the birth canal or even in the uterus before birth. If you have a kennel in which two or more bitches are producing litters and one loses a litter to herpes, what should you do to save the next litter? Besides the usual step of cleaning everything with a dilute bleach solution (as with parvo or other viral infections), you may find success by having your veterinarian inject them with serum obtained from the bitch that lost the litter. You may also succeed by keeping them in the high temperature environment mentioned above.
That, above, was the state of our knowledge in the last couple decades of the 20th Century. We had come only so far as determining that herpes had about 90% mortality in neonates. Now we may be on the brink of an advance in knowledge, unfortunately brought on by an alarming increase in failures in the dog breeding community. For some 10 or 15 years, I have been hearing more and more complaints about bitches not conceiving. And this is a day when companies like Synbiotics helped us zero in on the exact best time to inseminate. Progesterone, LH, and other hormones can be tracked with simple and fast test kits, and give far better accuracy than the vaginal cytology (study of the changing shape of cells lining the uterus) or the physical activity of the bitch or even the most jaded or experienced stud dog.
At least in the German Shepherd world, many of us have been blaming the fact that so many of our bitches were coming up empty on such supposed “reasons” as the use of anabolic steroids, known to be given to many of the top American (and perhaps other) show dogs in an attempt to boost their chances of being placed in the very highest positions at an annual national specialty, or even the preliminary competitions where success is considered in making judging decisions at the final big show. There is no doubt that this goes on to an unknown degree, and we know that many of the top human athletes in weightlifting, football, boxing, track, etc. are sterile or temporarily have a low sperm count.
But now, we may suspect another factor or two. The increasing use of too-frequent vaccines for any and all things is another target for blame for lack of conception and other concerns. That is, some want to point the finger at the effect of over-vaccination on the immune and other systems. Fewer people have other causes they want to blame, but it is a definite fact that greater numbers of people are not getting their bitches pregnant. Perhaps the new factor in the well-known (?) but poorly documented rise in number of failed matings is a newly recognized herpes variety. At least, some suspect it to be the cause of many of these. Nobody has been keeping statistics, so we can’t tell how many failed breedings are costing bitch owners money and time. While a few German clubs like the SV (for GSDs) will make note of such complaints, and withdraw rights from males that are shooting blanks, they will not hear from most disgruntled breeders. Stud dog owners are racking up the fees and bitch owners are getting poorer. Correspondents in England and Australia tell me it (failure to conceive) has been going on in their countries for some time, as it has in the U.S. Many cases are a matter of poor timing, but not all can be blamed on that. Recently, reports have come out of New Zealand and other far-flung places. Coming to a theatre near you! Freight and air regulations are prohibitive, Homeland Security has much adverse fallout, and even if you can get them, delayed repeat breedings with repeated air flights are a drain on the pocketbook. To add insult to injury, most Germans will not give you more than the time of day if you twist their arms for a second breeding because the first did not take.
Europe seems to have found out that it is real. In many growing pockets on the continent, breeders are using and reporting success with a new vaccine. In England, for example, friends tell me of scores of bitches supposedly infertile or nearly so have been producing very well after getting the vaccine. The word going around there is that if the bitch is vaccinated while in estrus or right after the bitch is mated, and again at 6 or 7 weeks in whelp, not only is it almost always successful, but larger litter numbers than expected seem to be the norm.
Right now, I know of only one company making the herpes vaccine, Merial. They have said that [rough translation]: “the herpes canine virus is an infectious and contagious disease caused by alpha herpes virus, which involves reproduction disorders, losses of pups mainly before 3 weeks, but also of infertility, abortions, and/or stillbirths. The vaccination which exists is used to protect the pups less than 3 weeks at which age one finds the clinical form most serious. The mothers receive an injection at the time of heats [estrus] and another injection one or two weeks before whelping. This is thus addressed especially to the professional breeders as well as to amateurs.” Merial also says, “Visit www.canineherpes.com for comprehensive public domain info.” and describes the virus and vaccine thusly: EURICAN Canine herpesvirus (F205) strain antigens; Indication: Active immunisation of bitches to prevent mortality, clinical signs and lesions in puppies resulting from canine herpes virus infections acquired in the first few days of life.
Merial information tells us, Like all herpes viruses, CHV is highly infectious, and a recent study showed that more than 80% of the dogs tested had been exposed to the virus at some time in their lives. Other studies have shown infection rates of 40-100% in kennels around Europe. They also note, Once the virus becomes established in kennels, periods of high mortality are interspersed with a general fall in the average birth weight of the litter and the existence of a problem only becomes apparent once a vaccination programme is put in place.
Merial is headquartered in Belgium, but has done much if not most of its business in France, although national borders in Europe are getting indistinct. French breeders I hear from tell me they are convinced the new herpes strain is the real cause of bitches not getting pregnant as well as a reputed increase in mummy puppies, absorbed fetuses, spontaneous abortions, stillbirths, and neonate mortality in the first three weeks. Whether this will be substantiated by scientific studies, I cannot forecast, but I am told that the herpes incidence there (France) in GSDs is now about 40%, and expected to rise to 80% in 2005. I know or have heard from many people around the world who have been mostly unsuccessful in getting bitches bred in the past few years. It might help if every breeder were to get their brood bitches vaccinated during their estrus period, and some say a booster shortly before whelping. American vaccine manufacturers are behind the wave on this one. A few years ago after Merial’s announcement, the few bitches that were benefiting (if indeed it works as Europe claims) were getting their vaccines smuggled in (undeclared in the luggage of people coming from Europe). That’s a risky way to get what you need, and would probably carry a greater penalty than what might be placed on gray-haired seniors bussing to the Canadian side of the river to get decent prices on their prescription drugs.
The epidemic (not really an accurate term here) is going to get worse before it gets better. Drug supply firms in the U.S. and other countries need to determine if indeed, the conception failures are due mostly to the virus, and that they had best get with the program and serve their customers! The AVMA and others need to address this fatal problem rather than meddle with the long tradition of tail docking with its two seconds of discomfort. While only a few mentions in Merial’s promotional literature (and zero professional journal articles so far) involve infertility affecting several bitches, one suggestion under their treatment guidelines is simply, Try the vaccine and see what happens.
To the question, If the bitch is already pregnant, is there any point in vaccination?, they respond in the affirmative: If possible, try and give two injections, even in the last few weeks of pregnancy. Even one injection is beneficial, though obviously the later it is given the greater the chance that the placenta will be damaged and the unborn puppies affected. Here again, the emphasis is mostly on the health of puppies already conceived or whelped, not so much on the failure to conceive. That is only brushed lightly.
My advice is to put pressure on the drug suppliers, veterinary colleges and AVMA to get the straight facts about the effect of herpes virus on conception failures; then, if there is confirmation of the anecdotal evidence, quickly make a vaccine available to breeders. We have already lost enough!
Other Reasons: While the greatest benefit of Merial’s vaccine is in preventing many spontaneous abortions, perhaps high-enough whelping-box temperatures could do the same thing at much lower cost. The vaccine’s benefit in helping to assure conception might be more important. But there are other causes for non-conception, of course. One person wrote me recently about the inability to get Boston Terrier bitches pregnant, and being just about to give up breeding. A friend suggested that she do a sensitivity test for bacteria near the uterus, and she did and put her dogs on an antibiotic. (Amoxicillin wasn’t doing the job.) I believe that they were put on Baytril. Since she began treatment she now has three very pregnant bitches. But E. coli and other bacteria, while almost as omnipresent as Herpes and Demodex, is relatively seldom the culprit. So, this and similar reports may be coincidental. We need more case studies.
More Likely: Of late, mounting evidence has convinced many of us that a primary reason for non-conception in healthy bitches is a subclinical thyroid hormone deficiency. The stubborn, hard-headed majority of the veterinary community has historically refused to consider the experiences of breeders in many areas, and failure of mated bitches to conceive is one of these. So many of us in the dog game (breeding and showing, not practicing medicine for others) have found that the established definitions of a healthy and totally functioning thyroid are erroneous. Through practical experience, we have found that “supplementing” with synthetic thyroxine around the time of estrus has resulted in many bitches conceiving whereas their owners had not been successful previously in getting them pregnant. And when shipping, other expenses, stud availability, and time are expensive factors, it becomes a serious problem. What the vets’ textbooks have told them are normal thyroid hormone levels is simply not true; not to the brood bitch owner who is footing the bills. The hang-up is that a simple, safe, economical cure (administering Soloxine or other-brand synthetic thyroxine tablets during estrus and pregnancy) is stubbornly resisted by vets who will not listen to clients. Despite the fact that thyroxine is extremely safe, even in larger doses than needed. Despite the fact that veterinary science originated with breeders. If only we breeders were as able to buy thyroxine over-the-counter as freely and cheaply as we can buy vitamin pills or aspirin, I am convinced that most of the missed breedings could be prevented. It took about a hundred years for veterinarians to admit that the number, volume, and frequency of vaccines they had been pushing were more based on pecuniary (money) interests than on science. I fear that the same foot-dragging will keep breeders from obtaining thyroxine on-demand, if not over-the-counter.