EQUIMAX™ is an FDA-approved, all-in-one dewormer that combines ivermectin and praziquantel to safely and effectively rid horses of all major internal parasites, including tapeworms, in a single dose.
Key Features
EQUIMAX is as effective as ivermectin against major parasites, as well as 100% effective against tapeworms, Anoplocephala perfoliata.
EQUIMAX can prevent tapeworm-associated colics, due to the control of A. perfoliata.
Contains enough smooth, highly palatable and quick-dissolving paste to treat horses up to 1,320 lbs. in a single application.
Packaged in an innovative applicator that allows for easier, more accurate dosing.
6.42g -
http://www.pfizerah.com
Information on specific parasites (from "The Horse")
Ascarids (Roundworms)
The roundworm begins its life cycle when the horse swallows eggs, which can be found anywhere in the environment. Roundworms most often afflict young horses. As the horse matures, he develops some immunity. However, by that time damage might already have been done by the migrating parasite.
Eggs hatch after they are ingested by the horse. Internal damage can occur in the wake of hatching as the larvae burrow into the walls of the small intestine and, in the next stage, migrate into the veins. At this point, the larvae have their own highway for travel as the bloodstream carries them through the liver and heart. Eventually, the larvae are deposited in the lungs.
While in the lungs, the larvae find their way into the air sacs. Irritation to the air sac causes the horse to cough. When he coughs, the larvae wind up in the mouth. They then are swallowed and once again take up residence in the small intestine where they grow to maturity. Roundworms might attain a length of one foot. If left unchecked, they can accumulate by the hundreds and grow in size to the point where intestinal blockage is the outcome.
But that's not the end of the story. While roundworms line the small intestine, growing ever larger, the female roundworm is busy laying eggs that are passed out in the feces, and the whole cycle starts all over again. One female roundworm is capable of laying 200,000 eggs per day.
The roundworm is difficult to combat for several reasons. The eggs are very hardy and resistant to a variety of adverse weather conditions. Infective eggs can remain viable for years in contaminated soil. This means that undisturbed eggs might lay in a pasture or paddock for long periods of time and remain capable of infecting the equine which ingests them.
Virtually all dewormers are effective in combatting roundworms. Horse owners should consult their veterinarians to learn what is best to use in their specific areas.
Small Strongyles
Strongyle eggs hatch when the temperature exceeds 45°F. They survive much longer in cold conditions, but no more than two weeks in hot weather. Moisture helps their survival; desiccation (drying out) is rapidly fatal. After being ingested, the larvae burrow into the wall of the large intestine, where they develop into fourth-stage larvae or, as they are referred to by parasitologists and veterinarians, "encysted cyathostomes."
When the larvae are encysted within the tissue (where they can remain for several weeks up to 2 1/2 years), they aren't causing much inflammation in the horse. However, when they emerge, especially if the emergence is in large numbers, the mucosal lining of the gut becomes inflamed. The result can include mild to severe colic, anemia, severe diarrhea, and weight loss.
After emerging, encysted cyathostomes mature into adults and produce eggs, which are excreted in the feces. After the eggs hatch, larvae molt twice and become the third-stage larvae, which can be present on the grass. They are ingested by grazing horses, and the cycle starts all over.
There are a number of dewormers that attack small strongyles. These include fenbendazole, oxfendazole, oxibendazole, moxidectin, ivermectin, piperazine, pyrantel tartrate, and pyrantel pamoate.
Large Strongyles
While large strongyles are still around and are capable of doing damage, they are no longer public enemy number one in the internal parasite world. That designation has been taken over by the previously described small strongyles.
The prime weapons involved in the demise of a great many large strongyles, says Craig Reinemeyer, DVM, PhD, of East Tennessee Clinical Research, are larvicidal dewormers. If a horse herd is well-managed and larvicides are used, he says, large strongyles can be eradicated. The key to eradication is to use a larvicide at least every five months and to maintain this program for at least 1 1/2 years. It's also essential to deworm any new arrivals with a larvicide and keep them confined for three to four days before turning out to pasture. Although the large strongyle has been beaten down on well-managed farms, it has not been eradicated and can still be found in populations that are not dewormed regularly.
Large strongyles cause damage as they migrate in the walls of intestinal arteries and other organs, triggering a chain reaction that starts with inflammation and ends with blocked blood flow to part of the horse's intestinal tract.
Tapeworms
The tapeworm is a different breed of internal parasite because it needs an intermediate host--the oribatid mite--which exists free-living on pastures. The infection process begins when tapeworm eggs pass in the feces of the horse and are ingested by a pasture mite. Within two to four months, the mite will harbor a stage (cysticercoid) that is infective to horses. Six to eight weeks after an infective mite is eaten by a grazing horse, the tapeworm matures and begins laying eggs. Large numbers of tapeworms can cause ulceration in the large intestine and cecum, colic, and intestinal blockage.
One dewormer used to fight tapeworms has been Strongid (pyrantel pamoate) although technically, it has no label claims for efficacy. However, say officials of Pfizer Animal Health, manufacturer of Strongid, there has been lots of recent research on equine tapeworms. Some findings are that tapeworms afflict far more horses than previously thought. Pfizer is in the final stages of developing a new product for combating tapeworms.
The Bountiful Bot
Many of us have observed horses in the middle of summer zooming about the pasture in a vain attempt to escape swarms of annoying flies. If you see an insect that looks something like a honeybee buzzing industriously around your horse's legs, chances are it's not a bee but an adult bot fly, looking to deposit her yellow eggs on the horse's leg hairs with the long, curved ovipositor attached to her striped abdomen. Female bot flies are often observed on warm, sunny days hovering near horses and darting in rapidly in an attempt to attach eggs with a sticky "glue" that makes the eggs adhere tightly to the leg.
Bot flies are common virtually everywhere horses are kept, with two major species found in the United States. Gasterophilus nasalis lays its eggs on the hairs of the intermandibular space (under the jaw). The eggs hatch spontaneously five to six days after being deposited, and the larvae crawl downward to the chin until they pass between the lips.
In contrast, the females of G. intestinalis lay their eggs on the hairs of the forelegs and shoulders of the horse. Far removed from their destination, the eggs depend on assistance from the horse to find their way into the mouth. Five days after the eggs are laid, they contain first-stage larvae that are ready to hatch rapidly in response to the sudden rise in temperature that occurs when the horse brings its muzzle in contact with them. When an itchy horse rubs and scratches himself with his muzzle and teeth, this allows the larvae to enter the horse's mouth and burrow into the epithelium (skin) on the top of the tongue.
Third-stage larvae attach by their mouth hooks to the wall of the stomach or duodenum for up to 12 months.
As maturity beckons in late spring, the larvae release their grip on the mucosa and pass out with the manure to pupate (mature into adult flies) in the soil. Adult bot flies emerge from the pupae in three to nine weeks depending on the ambient temperature and start the cycle anew. (There is generally only one generation a year.) Bot fly activity continues throughout the summer and fall, but ceases completely with the onset of cold weather.
The oral lesions caused by migrating first- and second-stage larvae can be extensive, and they can have an impact on your horse's oral and dental health.
Most horses can support substantial populations of these parasites without apparent disease. This is not to say that bots don't have an impact on the horse's health; their presence can cause disease too subtle for current detection methods. And particularly heavy Gasterophilus infections have been associated with subserosal (membranous) abscesses and gastric ulceration.
Threadworms
The genus Strongyloides (commonly called the threadworm) is mostly of concern in foals. The species that infects horses, S. westeri, is commonly transmitted from mare to foal through nursing, a mode of transmission with important implications for disease induction and control. Larvae in the tissues of mature mares are induced to migrate to the mammary glands by the hormones of pregnancy and lactation, so they're present in colostrum and in the first few days of milking.
Mares infected with S. westeri are asymptomatic, but once the larvae find a home in a foal, they mature rapidly in the small intestine. Within 10 to 14 days after birth, foals begin to shed eggs from the parasite. Diarrhea is a possible sign at this time. These "foal scours" can be coincident with the mare's first return to estrus, and numerous investigators have questioned the correlation between infection with S. westeri and foal heat diarrhea, although no definitive connection has been established. Heavy infections in foals can persist for 10 weeks, while lighter infections can last two to three times as long. Fortunately, horses develop immunity to these worms by about six months of age, and egg-shedding is never seen in mature animals.
Pinworms
Most horse people have heard about Oxyuris equi, the pinworm, a common and fairly large parasite with a long, tapering tail (hence the name).
Pinworms lurk in the large intestine. Instead of simply discharging their eggs with the horse's manure, the females migrate through the rectum and cement their eggs in masses to the skin around the anus. Each mass consists of a thick yellow or gray fluid, containing up to 60,000 eggs. The eggs develop into the infective stage in four to five days, during which the cementing fluid dries and cracks, allowing for detachment from the skin. The flakes that fall away from the skin adhere to mangers, water buckets, and walls, effectively contaminating the environment of the stable. If a sponge or towel is used to wipe down the horse's perineum following work or grooming and that sponge is used again to clean a bit, transmission has been accomplished for the
pinworm. The entire life cycle for these parasites takes up to five months to complete.
Severe infections with third and fourth stage larvae of O. equi can produce inflammation of the cecal and colonic mucosa, resulting in mild colic signs. The most common problem associated with pinworms in horses is the intense itchiness caused by the adhesive egg masses. In an effort to relieve the itching, horses will rub their tail heads against any surface they can find. Numerous horses have lost beautiful tails thanks to pinworm eggs. Cleansing the perineum with paper towels and warm water will give an affected horse some relief.
To view more information on deworming your horse see the following:
Waging War On Equine Parasites
Parasite Control Tips
Tapeworms
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