MICHELLE ASKS:
The first of this year, I had a Miniature bitch who got the bad strain of Parvo which went through so many kennels. She recovered, and I was told that she would never get Parvo again. I have several questions pertaining to this.
If I breed this bitch and she has a litter, will the puppies have a higher resistance to Parvo in general or just to the strain the mother had? Will they have a high resistance to any strain of Parvo?
What about the DA2PPCV series – can we wait until the puppies are older (about nine weeks) to give them their first shot? Can we wait a longer period between shots instead of the normal three weeks?
After the mother’s bout with Parvo, how long will the puppies keep the immunity they received from her before they need a shot to be safe from Parvo?
DR. JOE ANSWERS:
These questions are somewhat complex and I am not sure where to begin, so I will start with the statement, “I was told she would never get Parvo again.” In general, this is true. The only exception would be if she were to have any condition (or be taking any medications) that affected the ability of her immune system to respond to an exposure to Parvo. The reason she would have “permanent immunity” to Parvo is because the immune system has a “memory” and would be able to respond to the presence of Parvo fast enough to prevent contracting the disease. This is the same process that occurs in a regularly vaccinated dog. The reason that a dog who has survived Parvo usually does not need to be vaccinated again is that this “memory” in the immune system has been “stimulated” much more intensely than is possible with a vaccination. This extreme “stimulation” of the immune system (that occurs from having and surviving Parvo) allows a dog to “respond” quickly to exposure, even when the actual antibodies to Parvo in the bloodstream are much lower than would be present in a regularly vaccinated dog. But, with a “survivor” or a vaccinated dog, resistance to Parvo (or any disease) depends on the immune system functioning correctly.
Sorry to tell you this, but the puppies of a bitch who survived Parvo may not have any greater resistance to Parvo than the puppies of a properly vaccinated dog, and actually may be less than that of a vaccinated dog if the survivor is not vaccinated again. Why? Because the level of temporary immunity that the pups receive from the bitch’s colostrums is dependent on the circulating antibodies to Parvo in the bitch at the time she begins lactating. These circulating antibodies will be high in a recently vaccinated bitch, but if a bitch who has survived Parvo is not revaccinated, as time goes on, if she is not naturally exposed to Parvo, then her circulating antibodies will diminish significantly. While she herself would be able to respond adequately to an exposure, the pups may not have received adequate levels of Parvo antibodies since her antibody levels may have dropped significantly over time (if she was not either vaccinated for or naturally exposed to Parvo).
We all try very hard to limit any natural exposure to Parvo in our dogs. We keep out strays. We make sure no unvaccinated dogs are brought into our kennels. We try to keep away flies (which may carry Parvo as they visit feces from other dogs). The list goes on and on. So, an unvaccinated Parvo survivor may have very low circulating antibodies for Parvo. Even vaccinated bitches can drop their levels of antibodies depending on how recently they were vaccinated. Some recommend vaccinating “to-be-bred” bitches just before they come into heat, hoping to have the highest possible levels of antibodies at the beginning of lactation, without the risks of vaccination during pregnancy.
Your next two questions are really the same. I will try to explain the rationale behind the “series” of vaccinations recommended for puppies.
Long ago, research was done into the immunity transferred from bitches to their puppies (in the colostrums or “first milk”). It was studied for Canine Distemper virus. What was found was that unless there was a total failure of the “passing of temporary immunity” to the pups, all pups had maternal antibodies to canine distemper up until the age of six weeks. At six weeks, the temporary immunity started to “go away” in some pups. It was also found that all pups had “lost” their passive immunity to distemper at 12 weeks of age. Because the transferred immunity interfered with the vaccines properly stimulating the pup’s own immunity, the only vaccination that we could be sure would not be interfered with was one at 12 weeks of age (or older). But, some pups did lose the immunity (and interference with vaccinations) as early as six weeks of age. So vaccinations were started at six weeks of age. The research also proved that some were “losing” their temporary immunity in between, so a vaccination was “added” at nine weeks of age. When this vaccination schedule was combined with good “puppy raising” practices that prevented exposure to distemper, the vaccine protection was extremely good.
Then, in the late 1970s, Parvo virus came along. More dogs were vaccinated than ever before (because Parvo was even devastating in unvaccinated adult dogs). Before Parvo, annual vaccinations for the majority of dog owners consisted of just a Rabies vaccination. Breeders, who saw what Parvo did to very young pups, vaccinated and vaccinated and vaccinated. When pups who only got vaccines up to the age of 12 weeks (which was the “standard”) began getting Parvo at 4-6 months of age, it was quickly realized that the combination of “heavy” vaccinations and natural exposure was causing puppies to have temporary immunity to Parvo (and interference with vaccination) past the age of 12 weeks. It was determined that the temporary immunity to Parvo in many pups lasted until 15 or 16 weeks of age. Vaccine protocols were changed to include another vaccine at 15 weeks or older, and vaccine producers tried to make vaccines that would “overcome” maternal antibodies (the cause of the interference with vaccination) at an earlier age. The combination of these two things resulted in protecting most puppies (when the vaccination protocols were followed correctly).
So, what does this mean in terms of the vaccination schedule that should be used?
First, I would still vaccinate all breeding bitches, including ones that had survived Parvo, so that their circulating antibodies would be high and they would pass high levels of immunity to their pups. There are different ways to schedule the vaccinations for breeding bitches. Some just vaccinate yearly. Others vaccinate only the bitches about to be bred (just before they come into heat). Having their antibody titers tested is a great idea if it is not too expensive (it costs much more than a vaccination), since it would allow you to only vaccinate those bitches whose antibody levels were below “recommended” (no one knows what level really is best, but as more titer testing is done, the recommendations are being refined).
Secondly, I would NOT change the vaccination schedule for pups. “Failure of transfer of passive immunity” is not that uncommon. The passing of maternal antibodies to pups is a complex process. Antibodies are proteins, and to be effective, they must be absorbed whole, not digested by the intestinal tract. This only happens in the first 72 hours after birth. After that, the pup’s digestive system begins to function and the enzymes that help us digest consumed proteins will begin to digest the antibodies as if they were just any old protein that had been consumed.
Hopefully, this process occurs correctly, and the pups receive adequate antibody levels, but there can be variations even in pups from the same litter. One may have gotten more colostrums than another. One may have “correctly” absorbed the immunity less than another. There is presently no good way to identify which pups have more or less maternal immunity, so vaccinating all on a “time-tested” schedule is the best way to protect your pups.
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HANNAH ASKS:
If a Poodle that has an OFA “excellent” rated mother and a dysplastic father, will all the pups be rated “good” or “excellent”, or will some also be dysplastic?
DR. JOE ANSWERS:
Your question has two main problems:
First, by your description, you are referring to OFA evaluation of hips. OFA evaluation has one slight problem. It can give false “negatives” for hip dysplasia. In other words, not all dogs whose radiographs look “excellent” or “good” or “fair” are free from carrying the genes that can lead to hip dysplasia. Actually, because the normal radiographic positioning may actually tighten the hip joint’s appearance on the radiograph, sometimes dogs evaluate better than they actually are. The value of OFA evaluation is that a dog who shows as dysplastic is truly dyplastic.
Second, hip dysplasia, or at least the “expression” of hip dysplasia (a dog having true “clinical” hip dysplasia), is not entirely genetic. Let’s imagine two identical dogs (we are making them identical twins, which is not really known to occur in dogs), both having the same level of laxity (or tightness) to their hip joints. In addition, they are at the maximum laxity that will NOT result in their developing hip dysplasia (any looser joint, and they would be certain to develop hip dysplasia). One of those pups is never allowed to play on slick floors or other surfaces where they might slip and cause the hip joint to be stretched, and it is never allowed to grow too fast or gain too much weight (perhaps it is raised on large-breed puppy food).
The other puppy plays hard on slick floors, and is fed a regular puppy food and allowed to gain too much weight (thought to be “healthy” by the owners). The second puppy is at a much greater risk of developing clinical hip dysplasia than is the first, even though they are identical genetically. In the real world, it almost never occurs that pups in the same litter are completely identical genetically.
What should a breeder do?
First, the “rule” is that you don’t breed a dysplastic dog. As always, there are exceptions to every rule. Was the dysplasia a result of injury? Or, is it genetic? Obviously it is best not to breed the genetically dysplastic dog, but how do you tell?
I personally know of a breeding of two dogs that were evaluated as mildly dysplastic who produced a dog evaluated as good. We all know of good or excellent dogs who have produced dysplastic offspring. There needs to be a better system. And there is one that is better. It is called Penn-Hip. While it too has possible limitations, the main thing is that it doesn’t give a pass or fail to any dog. It is a system that rates dogs within their breed on a percentage basis (for example, your dog’s “score” is better than 60% of all the scores for that breed). Research on the method has proven that by only breeding dogs in the top 50% (the top half) of a breeds PH scores, the subsequent generations will improve over their parent’s generation. I urge you to investigate the ideas behind the Penn-Hip. Here is a link:
http://www.zianet.com/jornada/PennHip.htm
I know that Penn Hip is more expensive than OFA evaluation, but it can be offset by the ability to evaluate as early as 16 weeks of age. How much would you save by not having to raise a puppy to at least a year old to get “preliminary” OFA radiographs taken?
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JEANETTE ASKS:
How many days is too soon for a bitch to have puppies and how many days is too late?
DR. JOE ANSWERS:
Generally, 60 days is too soon and 66 days is too late, but there are exceptions to this; we all have heard stories about early or late pups. Many of these stories are probably due to incorrect recording of the actual breeding date, but I am sure there have been litters that did well that were just outside these ranges.
Early pups may not have enough of a substance called surfactant. Surfactant’s function is to help the lungs to inflate properly. Surfactants are substances that increase the “surface tension” of fluids. You cannot blow bubbles with distilled water, but if you add some soap (one kind of surfactant), you can make bubbles. The surfactant chemical that allows the lungs to inflate correctly is not produced in the pups’ bodies until rather late in the pregnancy (it is not needed until birth).
Think about that smaller, less mature-looking puppy you may have seen in a litter (from the “last” breeding??). It may struggle to breathe compared to the other pups in the litter. Given the fact that females are receptive for as long as nine days, you can have some pups born as much as a week “younger” than others in the same litter because of multiple breedings. Dogs carry for nine weeks, instead of nine months as in humans, so a week “premature” is like being a month premature.
For pregnancies going too long in the dog, the problem there is placental separation. Because a dog is a litter animal, simultaneous full separation of multiple placentas at one time could cause substantial bleeding from each area of placental attachment, all at one time. This is not healthy for the bitch, so, like other litter-bearing animals, the dog actually begins to separate the placentas beginning about a week before delivery. The attachment is essentially at the minimum “safe” amount at the time of whelping. Too many days at this reduced level of placental attachment can be harmful to the pups, since they get all their oxygen and nutrition from the placenta until they are born, and the reduced levels (due to the reduced attachment) are not good. The greenish color associated with the afterbirth is because of the placental separation and becomes greenish-black where there has been too long a time without delivery of the puppies. It is important to monitor any bitches that are “late” in delivering.
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