Unwelcome Guests - pets can have worms
W. Bradford Swift
How to help rid your pet of parasites pests.
As my new clients placed the wicker basket on the exam room table, I caught a glance of their new pup, a six-week-old black Lab, who was lying on his back fast asleep. "His belly is so roly-poly, we've thought of naming him that," said Ms. Matheson with a chuckle.
As I gazed at the new pet, my smile didn't come quite so easily. The round little pink belly was cute only if you didn't realize its cause. I tried to break the news gently. "You might want to keep searching for a name, because, hopefully, your little pup won't have quite so round a belly much longer. Potbellies like this are almost always a sign of worms in puppies and kittens."
I could tell from the shocked look on her face that my approach hadn't been subtle enough. "Oh no, Doc, what will we do? Will he be OK? I know I've only had him for a couple of days, but I'm afraid he's already become a member of the family."
"Not to worry, Ms. Matheson. We'll run a fecal exam to confirm the diagnosis and to determine what kind of worm he has, then we'll start him on a deworming program. We'll clear up the problem before it becomes serious, and in the process his roly-poly stomach will start to slim down to a more normal size."
Intestinal parasites, often referred to as worms, are a common problem in dogs and cats--especially puppies and kittens. The most common intestinal worms in cats are roundworms and tapeworms, while dogs most commonly harbor roundworms, hookworms, whipworms, and occasionally tapeworms. Early detection and elimination is the best course of action, so pet owners should be well informed about this potential problem, especially since roundworms and hookworms can be spread to humans.
Worms come in an assortment of sizes and shapes, from the large, spaghetti-like roundworms to the almost tiny hookworms. But all of them are considered parasitic because they cannot live without a host animal. Unlike some organisms, such as the microbes of the intestinal tract, that live inside another animal in a mutually beneficial relationship, intestinal parasites live to the detriment of the host.
According to John Malone, professor of veterinary parasitology at the School of Veterinary Medicine at Louisiana State University, close to 100 percent of puppies and kittens in this country have worms, even those coming from parents that are well cared for and have been treated for worms prior to pregnancy. This occurs because the worms spread from the mother to her offspring prior to weaning. In dogs, for example, roundworms are passed to puppies while still inside the womb, and hookworms are spread via the milk. In cats, roundworms are passed to the kittens through the milk.
Part of the reason these worms spread so readily to the young is that adult dogs and cats build up a partial immunity against the worms. As Malone points out, the immunity is never complete but is enough for many of the worms to become trapped in the mother's body in an encysted or premature form. These larval forms stay suspended in the body and never make it to the intestinal tract, where they normally grow into adults. They are unaffected by typical deworming medications and are able to migrate through either the placenta or the milk.
Many pet owners make the mistake of assuming that if they don't see worms, their pets must not have any. Unfortunately, this is often not the case. As parasites, intestinal worms need to stay inside the host in order to survive. So, it's an unsuccessful worm that leaves the host. According to veterinarian Carol Osborne of Vetsmart Care Clinic in Cleveland, Ohio, by the time you start seeing worms either in the stool or in the material your pet throws up, the animal is probably heavily infested.
The large roundworm is probably the most widely recognized worm, because of its size and the frequency of its occurrence in both dogs and cats. The adult worms spend most of their time in the stomach, although in a heavy infestation they can also be found along the intestinal tract. In this strategic position they get first crack at the food the animal eats, which leaves the pet nutritionally deficient. Pets become infected by swallowing roundworm eggs found in contaminated soil or feces, by eating infected rodents, birds, and certain insects, or by the mother transmitting the worms to her offspring.
Hookworms may be almost microscopic, but don't let their size fool you. They often occur in the hundreds or thousands. They attach to the sensitive lining of the small intestines, where they live off the pet's blood supply. In young, weak, or malnourished animals, hookworms can cause sudden collapse and death. Weight loss, diarrhea, and tarry or bloody stools are other signs.
Tapeworms can grow to be close to a foot long in some animals, although it's rare to see the whole worm, observes John Prange, a veterinarian in Kutztown, Pennsylvania. Most often pet owners notice small white segments, usually about a quarter to a half inch in length, either in the stool or along the rectal area of the pet. These segments break off from the end of the worm, leaving most of the worm still attached to the intestinal tract. Tapeworm segments may also dry up and look like a grain of rice stuck to the fur. Tapeworms don't pass directly from pet to pet but require an intermediate host in which to develop. Intermediate hosts include fleas and small animals, such as mice, rats, squirrels, and rabbits.
Whipworms, small, thin worms that live in the cecum and large intestine of dogs, often lead to chronic diarrhea and a drawn, haggard appearance. According to Osborne, whipworms shed their eggs only intermittently, making them difficult to conclusively diagnose with a fecal flotation exam, the most common test veterinarians use to detect worms. Therefore, it's not uncommon for experienced veterinarians to treat a pet with chronic diarrhea for whipworms without a conclusive test, especially if no other cause of the problem can be found.
According to Osborne, one of the most common fallacies among pet owners is the assumption that their new pet has had all its preventive care completed by the time they acquire the animal. Although most veterinarians recommend that deworming of puppies and kittens begin as early as two to four weeks of age and be repeated every couple of weeks until about eight weeks of age, the process isn't over at this point. Growing pets should be checked once or twice more for worms during the next three to six months because it's so easy for them to be reinfested. And even though older animals develop a partial immunity, they are never completely protected, so an annual or semiannual check is important for them as well. Luckily, there are preventive medications to combat most of the common intestinal parasites that occur in dogs. One of the most effective is Sentinel, a product introduced by Novartis Animal Health in 1997. When administered monthly to your dog, it prevents heartworms in addition to treating and controlling whipworms, hookworms, and two types of roundworms. An added bonus is that Sentinel also eliminates fleas by preventing them from reproducing, which also reduces the risk of tapeworms.
Kittens are commonly treated for roundworms with one of several different medications, and for tapeworms if the segments are seen in their stools. Because of their cleaner habits, adult cats are less prone to heavy cases of worms than dogs, although they can easily contract tapeworms from ingesting a flea or from eating small rodents.
Besides checking your pets once or twice a year for worms, it's important to keep their environment as clean as possible of fecal buildup. Remember, worm eggs can come out in the stools and can then be ingested by a pet to start the cycle all over again. In the case of hookworms, the eggs can hatch into larvae, which can then penetrate through the footpads and resume the cycle. According to Malone, most intestinal worm eggs and larvae cannot survive long in direct sunlight but can survive quite well in moist, shady areas. He recommends stools be picked up on a regular basis before the eggs have had an opportunity to hatch into infective larvae.
Hookworms and roundworms can also be spread to people, especially children who play outdoors without shoes on or ingest dirt. While the prevalence of such infections varies with climatic conditions, it is a potential problem in all parts of the United States and should be considered a potential public-health hazard.
While intestinal worms can be a serious problem, they don't have to be. Working with your veterinarian in a thorough treatment-and-prevention program can help assure your pet's health and aid in maintaining your family's safety. While your puppies and kittens may not be quite so roly-poly, they will be a whole lot healthier and happier.
Veterinarian W. Bradford Swirl is a contributing editor to Animals.
COPYRIGHT 1999 Massachusetts Society for the Prevention of Cruelty to Animals
COPYRIGHT 2004 Gale Group
It seems odd but yes, they often have worms from the mother and it is always wise to assume they have them. That is why it is important to worm them. A pup can decline and die from a bad load of worms -- this is a common cause of death in puppies that come into rescue (along with parvo).
