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Photos and expert help for a swimmer puppy with flat chest, wobbly legs, can't stand up or walk normally due to inner ear and righting reflex problems.





Fred Lanting, SAAB Member and All Breeds Dog Show Judge


A puzzling phenomenon is the litter in which one or more of the whelps become strangely deformed in the first two weeks of life. A flattening of the thorax and abdomen, top to bottom, becomes evident about a week after birth from some unknown cause.


Swimmer pups happen most often in the dwarf (chondrodystrophic) breeds but "swimming" has been seen in other breeds. Instead of the thorax developing normally into a progressively deeper tube from the prosternum/neck area to the diaphragm, it forms more of a flattened cylinder. The forechest, instead of dropping from the prosternum to the last sternal vertebra, may even be concave and as time goes on the puppy may become even more flat-chested and pancake-shaped.


Recognizing A Swimmer Pup

There is some variation in swimmer severity and symptoms but as the ribs bow out, the heart and other organs may be pushed into the pleural cavity and displace or decrease the air volume of the lungs.  As a result, untreated pups become lethargic, lacking in energy and strength.


By the third week when normal puppies would be up walking, surviving swimmers have not yet learned to push themselves up into a standing position. If the extended limbs, especially front legs, are moved at all, it is with a paddling motion to the sides, hence the disorder is often called “Swimming-Puppy Syndrome.”


The hind legs typically are extremely weak; they may be tucked under the torso, or extend behind the pup but in any case they have little or no movement. If corrective swimmer therapy is not instigated early, swimmers have very poor circulation, respiration, and ability to swallow food or keep milk in their stomachs. When they are old enough to wean (if they live that long!) swimmers are very slow when eating from pans.


If swimmers are not given some sort of therapy, there is a less-than-even chance they will survive to eight weeks.


What Causes Swimmer Pups?

Many factors have been attributed to the swimmer pup syndrome, both environmental and some of unknown genetic origin. For a while, most people blamed slippery floors but I’ve raised all my litters on smooth, impervious flooring covered with newspaper and have never had a swimmer. Some reports mention rough surfaced indoor/outdoor carpeting. I disagree, especially with recommending the use of carpeting, as this surface is notorious for harboring germs and thus causing other health problems.


Helpful Therapy For Swimming Puppies

Some breeders are fairly successful in correcting the swimmer syndrome by putting each of the pups in a sling for at least part of each day. This practice encouraged them to make contact with the floor with their pads. Some tied hobbles to the front legs to keep them under the body and the elbows close together. This, they felt, prevented the front legs from becoming spread-eagled.


Other swimmer therapies that may be beneficial although time-demanding of the breeder, include massage (passive exercise) and suspension in warm water. The swimmer therapy is promising if either active or passive movement can be induced. Thus, swimming (the real kind, in water) may even help correct the “swimmer” syndrome. Therefore, hold him in your hand or a sling, with support to keep his head up out of the water, and let him paddle for a while in warm water. Avoid chilling, remembering his temperature is 101 degrees.  Stop and dry him thoroughly when he tires.


As many of these sessions as you can manage should help the swimmer pup to develop coordination, muscle development, and better circulation while putting much less weight on his body. Your hand or makeshift sling plus the buoyancy of the water will take the weight off the chest.


Genetic and Ethics Of Flat-Chested Puppies

Starting in 1999, after much of the above was printed in my book “The Total German Shepherd Dog” (2nd edition), a French Bulldog breeder expressed the belief that a dam that produced this defect should not be spayed or eliminated from the breeding program. At first I disagreed with her because I am a hereditarian, but later came to feel that breeding her again might not be all that much of a risk. This lady had two swimmers, each 12 oz at birth, never left on flat surface. She said she put them on blankets, “facing upwards and they stayed in an upright position,” and claimed they were both fine within weeks.


Swimmer Puppy Syndrome is usually evident by 2 weeksThe syndrome of swimmer puppies is sometimes referred to as Pectus Excavatum, and described by many as “a condition of so-called flat-chested puppies.” Without intervention, and often despite best efforts, they usually die anywhere from two days to four weeks. More often it is sooner than later, according to the Bulldog people I have heard from.


Some breeders prefer not to assign any blame to genetics. They disagree with those who hold that the puppy inherits most problems from the parents and that a pair that produces a swimmer puppy should be removed from one’s breeding program.


People often postulate that the bitch was fed inadequately or that she did not utilize the necessary dietary nutrients (i.e., vitamins, proteins, fats, or minerals) to give the puppy the “skeletal components needed.” This may be stretching credulity, as swimmers also happen in households of experienced breeders and to bitches whose diets are normal. Others who refuse to acknowledge the major part that genes play tend to blame environments such as too flat or too hard or too slick a surface, bacteria, viruses, etc.


A breeder of Lhasa Apsos and American Cocker Spaniels corresponded with me after reading the section on swimmers in my “Total GSD” book. She had become frustrated with the feeble answers from “experts". What she observed was “the swimmer syndrome began to show up at anywhere from one hour to a couple of days after birth, beginning with a slight flattening of the chest or an actual bend in the ribs.” I believe that by careful observation, she hit upon a method of early identification of afflicted pups and possibly, therefore, carriers of the defect.


I am enough of a eugenicist to want to remove carriers of a defect from a gene pool but enough of a “compassionate conservative” to want to save any pup that could possibly live a useful life and bring someone happiness. Swimmer pups that are saved should perhaps be neutered.


Swimming Puppies and Righting Reflex

The Lhasa-and-Cocker lady became adept at determining if a pup has a problem by picking up each pup and testing its “righting reflex.” She correctly stated, “What you will notice about these swimmers is that they are always lying flat on the belly. If you lay them on their side, they will immediately return to lying on their bellies."


It is true that the normal neonate has an instinct to get onto its belly and crawl or drag itself to a teat. Once there, it may just as easily and happily again flop over on its side a little. After nursing, the normal newborn pup will lie on its side to sleep.


This photo shows puppies actively nursing and the two that have fallen asleep, on their sides. As they get old enough for the ribcage to have developed strength, they may sleep belly-down for a while but by then it is not abnormal.


Occasionally a puppy seems to indicate that it doesn’t want to or cannot return to a normal relaxed state on its side. This is possibly not a defect in the righting reflex, per se, but a genetic defect in proprioception, the instinctive knowledge of position. It may well originate in a genetic defect in the embryonic development of the inner ear.


Swimmer’s Ear and Swimmer Pup Syndrome?

The ear is divided into three parts: outer, middle, and inner. The outer part helps funnel sound to the eardrum, a membrane on the other side of which is the middle ear. There, three bones hinged together relay eardrum vibrations to the inner ear, which is separated by more membranous tissue. The inner ear includes not only the nerve endings that transform mechanical movement into electrical impulses and carry auditory messages to the brain, but it also includes the organ of balance.


The rear part of the membranous labyrinth has three semicircular canals that look like three bicycle tubes joined together in one bulbous end. Each of the three canals is oriented 90 degrees to the other two, and all are filled with fluid and nerve endings. The tiniest movement of the body tells these moving-fluid-activated nerves what direction the head is turning and thus informs the brain as to what muscles must contract in order to change or return to a given position.


It is my hypothesis that in swimmers, the message is not being relayed or is misinterpreted somewhere along the chain of events. We also see similar interruptions in these messages in older dogs caused by infections, poisoning, or late-developing genetic factors. It may be that the messages coming from the legs are not getting to the brain or spinal cord, nor going in the return direction.


The “cure,” if you want to call it that, will only be for the individual puppy. If it is indeed a genetic problem, correcting the condition in an individual puppy does not erase the cause. If your breed has been known to have swimmers or you are slightly paranoid by nature, steps to identify and correct could be quite simple.


We are told to check all the pups right after birth and every hour or so for the next couple of days. (I don’t know about you, but I have to sleep sometimes.) If you notice a pup that is always on its belly or beginning to show signs of a flat chest, put that pup on a good nipple, turn it on its side, holding its entire body and making sure it stays on its side. Sit close by and watch. If the pup lets loose… start over. Do this several times a day until the pup returns to normal… on its side.  When that happens, you have just cured swimmer puppy syndrome.


You will have to determine for yourself if it is worth it. And if it happens more than once in a litter from either parent, perhaps the surest and safest approach is not to breed either parent again. The longer I live, the more evidence I see that nearly everything has a bigger genetic component than you would initially think.


Surviving Swimming Pup Syndrome

A friend and fellow judge in Pakistan, who is one of his country’s most notable breeders, wrote to me late in 2010 for advice. He related, “In my Labrador Retriever litter, I had a swimmer pup. I noticed it when the pup was about 16 days old. By three weeks, his hind legs would stretch back like a turtle and also go sideways. Front legs were OK and he could lift his chest and move with his front legs. He had a flattened chest. I tied his rear legs with an elastic ribbon, keeping it only as wide as his body. I made a loop around his neck also and tied [the cord running under the belly] to the elastic band joining the two hind legs. I did this to ensure the rear legs did not stretch back. Within three days, he started walking on his own (with elastic bands) and after another week started jumping around without any bands. Now he runs about and it is very difficult to spot it from his litter mates. His chest is absolutely normal. Litter is now five weeks old.


After reading your article in detail, I want to know whether, in the swimmer puppies, the chest is flattened because of splayed legs or the legs are [spread out] because pups are born with flat chest. My other question is, will my pup have any after-effects later in life or will be normal?


I told him it is most widely believed that the problem is a congenital weakness that develops when the pup does not have the neurological stimulus (or muscle response) to control the early placement and use of limbs. Without this normal nerve development, the muscles are not ‘trained’ to respond when signals are sent from the brain or spinal cord. Apparently, the breeder’s act of positioning the limbs under the torso somehow allows this nerve impulse ‘send-and-response’ procedure to establish a ‘habit’ (which you could call the system’s development of ‘memory’).


The later a breeder attempts to correct the problem, the less likely the pup will develop normally. The longer one waits to reposition and train the limbs, the more permanent will be the damaging effect on lungs and other internal organs. If ignored, apparently it will lead to death, although there are no reliable statistics. I have never heard of the problem resolving spontaneously — without human corrective intervention.


In answer to the question of which came first, the chicken or the egg, I would say that the nervous system defect is the cause, and the flattening of the chest cavity is a result of this lack of stimulus to the limb muscles to move them under the body and push the torso up, sideways and forward.


Until I see such a hint of familial relationship, I would guess it would be safe enough to breed dogs that were affected with this syndrome in the whelping box but keep good records on future relatives’ puppies. It very well could be what many people call a “non-genetic” (but by which I personally mean low heritability) trait, one that is less influenced by genes and more influenced by environment — including the biochemical environment in the uterus.


So, as in any abnormality whether very slight or more serious, the breeder needs to decide whether to try to eliminate or limit it, or to let it go and concentrate on more important things. In any case, it is a matter of ethics and good science to be diligent in keeping records on where swimming puppy littermates go and whether the condition appears again in those lines.

Copyright ? 1509203R214



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