By Dr. Julie Cornell-White
Cause damage without owner knowing Internal parasites can:
Lower horse’s resistance to infection Rob horse of nutrients Permanently damage internal organs
Types of parasites and affects on horses Signs of Parasitism Different deworming programs Various deworming products Proper pasture management
Most Common:
Large Strongyle (Bloodworm/redworm) Small Strongyle Ascarids (roundworms) Tapeworms Lungworms Pinworms Threadworms
Dull, rough coat Decreased stamina, lethargy or depression Unthriftiness or loss of condition Slowed growth in young horses Pot Belly Colic Diarrhea
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Larvae penetrate lining of bowel and migrate along blood vessels that supply intestines
Unthriftiness Weight loss Poor growth in your horses Anemia Colic They can be controlled using macrocyclic lactones and related dewormers
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Larvae burrow into the lining of the intestines where they are encysted for several months When encysted, most dewormers do not affect the larvae
Severe damage to lining of intestines Colic and diarrhea Weight Slow growth in young horses Poor coat condition Lethargy Use dewormers with Moxidectin and Fenbendazole
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Especially problematic in young horses Becoming resistant
Colic-impaction of intestines Coughing Poor body condition and growth Rough hair coat Pot belly
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Can cause colic ranging from mild cramping to a severe episode
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Tiny mite acts as an intermediate host that is ingested by the horse Infestation usually occurs where small intestine enters cecum
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Worm horse 1-2 times per year with a dewormer containing Praziquantel or Pyrantel
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Cause chronic coughing Donkeys are natural host
Lay eggs on skin around horse’s anus
Causes horse to rub tail
Larvae of botfly enter mouth when horse lick’s eggs Cause ulcerations in mouth Cause damage to lining of stomach where they attach
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Mostly problematic in young foals Cause diarrhea
FECs help determine:
Drugs to use Which horses require less and more deworming Length of time between dewormings The effectiveness of your deworming program
Negative results DOES NOT MEAN your horse is free of internal parasites
Larvae are undetectable with FEC
Use broad-spectrum dewormer as basis of program No dewormer is 100% effective, but eliminating majority of parasites will:
Improve health Minimize risk of serious disease Improve feed efficiency Reduce pasture contamination
Two basic types if deworming programs:
Continuous-feeding daily wormer year-round Strategic or rotational-deworming only at certain times of the year, or when FECs rise
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http://www.saratogaequine.com/vaccination deworming.php
Type of horse # of horses on farm Ages of horses Pasture management Geographic location
Don’t overcrowd pasture-causes overgrazing and contamination Dispose of manure regularly Don’t spread manure on grazing pastures Mow and harrow field regularly Don’t feed on ground Remove bot eggs from horse’s hair coat