Your long-awaited foal is finally here and he’s perfect. Of course, you’ll want to protect his health from the start and that will include keeping internal parasites in check. Ideally, his dam has been on—and will stay on—a targeted deworming plan, which will offer him some protection. Even then, however, a new foal will pick up parasites from the environment, so you’ll want to be prepared to protect his health.
Know your targets and tools
When formulating a strategic deworming protocol for young horses, it’s essential to first understand which parasites you’ll be battling and the chemical classes that are effective against them.
The most significant parasites in young horse are ascarids, also known as roundworms. They tend to prey on foals less than 18 months and can affect a variety of body systems, causing respiratory disease as they migrate through the lungs, stunted growth, diarrhea and—if allowed to amass in large numbers—potentially fatal impaction colic. While ascarids have developed resistance to some other drug classes, benzimidazoles are still generally effective.
Young horses are also vulnerable to large strongyles, sometimes called bloodworms. Strongyle infection can lead to loss of appetite, weight loss, weakness and diarrhea. Macrocyclic lactones, like ivermectin and moxidectin, are effective against these parasites.
While they are rare in foals younger than seven months old, tapeworm infestations can occur in young horses. Clinicians have observed an association between tapeworm infection in weanlings and yearlings and ileocecal colic. The chemical praziquantel is effective against tapeworms, as is a double dose of pyrantel pamoate.
When choosing deworming products, be sure to read labels carefully determine how early they can be used in foals. Not all formulations within the same chemical class have the same age guidelines. Equimax® (ivermectin 1.87% / praziquantel 14.03%) Oral Paste, for instance, is labeled for use in foals as young as four weeks old. Also, use a weight tape to estimate the weight of your foal for accurate dosing.
Formulate a plan
Although targeted anthelmintic treatment utilizing fecal egg counts (FEC) is recommended for mature horses, that approach alone isn’t optimal for deworming foals. Instead, the American Association of Practitioners recommends a minimum of four treatments, utilizing FEC as well as set treatment protocols:
- Between 2 and 3 months of age: First deworming with drug to target ascarids.
- Just before weaning, about 4 to 6 months of age: Second deworming with a product to targeting either strongyles or ascarids, depending on the result of a fecal egg count.
- Nine months of age: Third deworming with a product targeting strongyles, and possibly a treatment for tapeworm.
- One year: Fourth deworming with a product targeting strongyles, and a treatment for tape-worm if that was not done in the previous deworming.
Defend on all fronts
In addition to thoughtful chemical control, you’ll want to ensure you’re managing your foal in a way to minimize his exposure to potentially harmful parasites. Do this by regularly picking manure out of fields, not overcrowding pastures and keeping new horses isolated until they’ve had a fecal egg count to determine their egg-shedding rates
Important Safety Information: Not for use in humans. Do not use in horses intended for human consumption. FOR ORAL USE IN HORSES 4 WEEKS OF AGE AND OLDER. Not to be used in other animal species as severe adverse reactions, including fatalities in dogs, may result. Swelling and itching reactions after treatment with ivermectin paste have occurred in horses carrying heavy infections of neck threadworm microfilaria (Onchocerca sp.). Ivermectin and ivermectin residues may adversely affect aquatic organisms; therefore, dispose of product appropriately. For complete prescribing information, contact Bimeda® at 1-888-524- 6332, or EquimaxHorse.com/PI. All trademarks are the property of their respective owners.