Parasites can be a big problem for horses and horse-owners to deal with. They can decrease performance, cause illness, and in severe cases, may result in death. Thankfully, there are many great products on the market, as well as good management practices, to help control the numerous types of parasites.
There are two main categories of parasites, external and internal. Common external parasites include mosquitoes, flies, ticks, mites, and lice. Mosquito, tick, and fly spray for horses is a useful tool for helping decrease the amount of external parasites your horses encounter. Most sprays contain a permethrin, but all-natural ones such as Spalding Laboratory's™ Bye Bye Insects™ (https://spalding-labs.com/products/fly_control_products/fly_sprays/default.aspx) are out there. Symptoms that commonly occur with most external parasites and the diseases they carry include: loss of condition; anemia; dry, patchy coat; diarrhea; itching; increased temperature and heart rate; colic; constipation or diarrhea; and loss of exercise capability.
Mosquitoes can be particularly harmful as they may transmit diseases such as eastern equine encephalitis (EEE), western equine encephalitis (WEE), Venezuelan equine encephalitis (VEE), and West Nile virus (WNV). While horse owners can't eliminate mosquitoes altogether, we can help prevent mosquito-borne diseases by consistently vaccinating our horses against these diseases. We can also help interrupt the mosquito life-cycle by making sure that we don't have stale, water sitting around, cleaning up or spraying pastures that tend to be wet with a product containing either Bacillus thuringiensis israelensis (Bti) or S-methoprene. Be sure any products you use are safe for use around horses.
There are many different varieties of ticks, and the kind you have and amount of each is determined by location. In western Nebraska we commonly encounter the American Dog tick. These ticks may transmit Rocky Mountain Spotted Fever and Tularemia. Black-legged ticks may carry Lyme disease, but they are not commonly found in this area. There are no vaccines for these diseases, but they may be treated with antibiotics. To prevent infection from a tick bite, try to remove ticks within 24 hours of attachment, and be sure to get the head out. To prevent ticks, use a tick-specific repellant. These usually contain coumaphos, permethrin, and/or zeta-cypermethrin. Reduce brush areas in your pasture (in Nebraska we should be especially concerned about Eastern Red Cedars) and if possible employ free-range chickens and/or guineas to eat the ticks.
One of the more painful parasites are flies, particularly biting flies such as stable flies and horn flies. These flies pierce areas of thinner skin and suck the horse's blood. They have painful bites that result in irritated, swollen skin. Houseflies and face flies do not bite, but irritate horses by feeding on the mucous around the eyes, nose, wounds, and manure. Flies help spread disease and infections from one host to another. A particularly dangerous disease they transmit is equine infectious anemia (EIA). It is highly infectious,is often fatal, and is incurable. If a horse contracts it and survives they must either be euthanized or quarantined for life. To help stop the spread of EIA, a Coggins test should be performed on all horses before they travel or compete. To prevent flies, keep manure away from the horses as much as possible, locate fly traps away from barn areas as these actually attract flies, and use fly sprays. You can also use a product such as Spalding Laboratory's™ Fly Predators™. These are tiny insects that do not bother people or animals but kill flies in the larval stage.
Common internal parasites include large and small strongyles, ascarids, tapeworms, botflies, pinworms, lungworms, stomach worms, and threadworms. Infestations of these may be prevented with proper pasture management, fly management, and a consistent deworming schedule. Almost all internal parasites are spread through either flies or through fecal matter in pastures. Rotating pastures, cutting hay right before winter, and spreading manure in hot pastures all help to kill the larvae and break-up the cycle. To determine what parasites your horse is hosting, have your veterinarian do a fecal egg count. Then buy a dewormer that is specifically for that parasite. Horses should be dewormed with anthelmintics once to twice a year, in the fall and spring. Dewormers should be rotated only when a resistance is detected. Constantly rotating dewormers actually leads to greater resistance.
Large strongyles are among the most deadly group of internal parasites. Infections can lead to weight loss, anemia, ruptured abdominal arteries, loss of circulation, and impaction colic, which is often fatal. They may damage the liver but most live in and damage the large intestine. Small strongyles rarely result in death but can still cause weight loss and anemia. Strongyles are most commonly treated with ivermectin and moxidectin.
Ascarids, also known as roundworms, most commonly cause issues in horses under the age of three. They live in the small intestine. Symptoms include weight loss, diarrhea, and colic. Thankfully a horse's immunity is built up with age. Ivermectin rarely works for treating ascarids, but they may be treated with pyrantel, fenbendazole and oxibendazole.
Tapeworms live at the junction of the ilieum and the cecum. Tapeworms cause nerve damage at the point of attachment. The most common symptom is colic. Nearly 22% of spasmodic colics may be attributed to tapeworms. They may be treated with either praziquantel or pyrantel pamoate.
Botflies lay their eggs on the horse, often the legs. When the horse itches or licks themselves, bots become attached to the tongue and gums. After incubation for about three weeks, they are swallowed and attach to the stomach lining. The greatest problem bots usually cause is irritation to the mouth. They may be treated with ivermectin. Infections can be prevented by removing eggs from the horse.
While pinworms are common in horses, they rarely cause problems other than irritation to the horse and irritation to the tailless horse owner. They may be treated with ivermectin and pyrantel pamoate. Areas where the horse may have rubbed should be disinfected to prevent spreading pinworms to other horses.
Sources
https://equimed.com
https://equusmagazine.com
https://www.horsehealthproducts.combattle
https://lancaster.unl.edu
https://spalding-labs.com
https://aaep.org
https://horses.extension.org
https://ker.com
https://www.veterinarypracticenews.com
There are two main categories of parasites, external and internal. Common external parasites include mosquitoes, flies, ticks, mites, and lice. Mosquito, tick, and fly spray for horses is a useful tool for helping decrease the amount of external parasites your horses encounter. Most sprays contain a permethrin, but all-natural ones such as Spalding Laboratory's™ Bye Bye Insects™ (https://spalding-labs.com/products/fly_control_products/fly_sprays/default.aspx) are out there. Symptoms that commonly occur with most external parasites and the diseases they carry include: loss of condition; anemia; dry, patchy coat; diarrhea; itching; increased temperature and heart rate; colic; constipation or diarrhea; and loss of exercise capability.
Mosquitoes can be particularly harmful as they may transmit diseases such as eastern equine encephalitis (EEE), western equine encephalitis (WEE), Venezuelan equine encephalitis (VEE), and West Nile virus (WNV). While horse owners can't eliminate mosquitoes altogether, we can help prevent mosquito-borne diseases by consistently vaccinating our horses against these diseases. We can also help interrupt the mosquito life-cycle by making sure that we don't have stale, water sitting around, cleaning up or spraying pastures that tend to be wet with a product containing either Bacillus thuringiensis israelensis (Bti) or S-methoprene. Be sure any products you use are safe for use around horses.
There are many different varieties of ticks, and the kind you have and amount of each is determined by location. In western Nebraska we commonly encounter the American Dog tick. These ticks may transmit Rocky Mountain Spotted Fever and Tularemia. Black-legged ticks may carry Lyme disease, but they are not commonly found in this area. There are no vaccines for these diseases, but they may be treated with antibiotics. To prevent infection from a tick bite, try to remove ticks within 24 hours of attachment, and be sure to get the head out. To prevent ticks, use a tick-specific repellant. These usually contain coumaphos, permethrin, and/or zeta-cypermethrin. Reduce brush areas in your pasture (in Nebraska we should be especially concerned about Eastern Red Cedars) and if possible employ free-range chickens and/or guineas to eat the ticks.
One of the more painful parasites are flies, particularly biting flies such as stable flies and horn flies. These flies pierce areas of thinner skin and suck the horse's blood. They have painful bites that result in irritated, swollen skin. Houseflies and face flies do not bite, but irritate horses by feeding on the mucous around the eyes, nose, wounds, and manure. Flies help spread disease and infections from one host to another. A particularly dangerous disease they transmit is equine infectious anemia (EIA). It is highly infectious,is often fatal, and is incurable. If a horse contracts it and survives they must either be euthanized or quarantined for life. To help stop the spread of EIA, a Coggins test should be performed on all horses before they travel or compete. To prevent flies, keep manure away from the horses as much as possible, locate fly traps away from barn areas as these actually attract flies, and use fly sprays. You can also use a product such as Spalding Laboratory's™ Fly Predators™. These are tiny insects that do not bother people or animals but kill flies in the larval stage.
Common internal parasites include large and small strongyles, ascarids, tapeworms, botflies, pinworms, lungworms, stomach worms, and threadworms. Infestations of these may be prevented with proper pasture management, fly management, and a consistent deworming schedule. Almost all internal parasites are spread through either flies or through fecal matter in pastures. Rotating pastures, cutting hay right before winter, and spreading manure in hot pastures all help to kill the larvae and break-up the cycle. To determine what parasites your horse is hosting, have your veterinarian do a fecal egg count. Then buy a dewormer that is specifically for that parasite. Horses should be dewormed with anthelmintics once to twice a year, in the fall and spring. Dewormers should be rotated only when a resistance is detected. Constantly rotating dewormers actually leads to greater resistance.
Large strongyles are among the most deadly group of internal parasites. Infections can lead to weight loss, anemia, ruptured abdominal arteries, loss of circulation, and impaction colic, which is often fatal. They may damage the liver but most live in and damage the large intestine. Small strongyles rarely result in death but can still cause weight loss and anemia. Strongyles are most commonly treated with ivermectin and moxidectin.
Ascarids, also known as roundworms, most commonly cause issues in horses under the age of three. They live in the small intestine. Symptoms include weight loss, diarrhea, and colic. Thankfully a horse's immunity is built up with age. Ivermectin rarely works for treating ascarids, but they may be treated with pyrantel, fenbendazole and oxibendazole.
Tapeworms live at the junction of the ilieum and the cecum. Tapeworms cause nerve damage at the point of attachment. The most common symptom is colic. Nearly 22% of spasmodic colics may be attributed to tapeworms. They may be treated with either praziquantel or pyrantel pamoate.
Botflies lay their eggs on the horse, often the legs. When the horse itches or licks themselves, bots become attached to the tongue and gums. After incubation for about three weeks, they are swallowed and attach to the stomach lining. The greatest problem bots usually cause is irritation to the mouth. They may be treated with ivermectin. Infections can be prevented by removing eggs from the horse.
While pinworms are common in horses, they rarely cause problems other than irritation to the horse and irritation to the tailless horse owner. They may be treated with ivermectin and pyrantel pamoate. Areas where the horse may have rubbed should be disinfected to prevent spreading pinworms to other horses.
Sources
https://equimed.com
https://equusmagazine.com
https://www.horsehealthproducts.combattle
https://lancaster.unl.edu
https://spalding-labs.com
https://aaep.org
https://horses.extension.org
https://ker.com
https://www.veterinarypracticenews.com
