Parasites of Equine Presented By: Dr. Fakhar-e-Alam Kulyar DVM, M.Phil CMS University of Agriculture Faisalabad Contact: fakharealam786@hotmail.com

1. Parasites of Equines
Dr. Fakhar-e-Alam

2. Parasites or worms can cause extensive internal damage to horse.
Signs of worm Infestation are:
 Poor Growth
 Weight Loss
 Decreases feed efficiency
 Colic
 Diarrhea
 Lethargy & depression

3.  Periodic lameness
 Loss of condition
 Breathing problems and coughing
 Foals that do not grow well may develop the condition of pot bellies
 Pneumonia

4. Life Cycle of the Internal Parasites
Egg/Larvae Ground/Grass
Horse

5. Types of Internal Parasites:
There are more than 150 species of parasites that can affect the horse.
 Large Strongyle (Blood Worms or Red Worms, Stongylus vulgaris, S.edentatus,
S.equinus)
 Small Strongyle (Cyathostemes)
 Round Worms (Ascarids)
 Tape Worms (Anoplochephala)
 Lung Worms (Arnifeldi)
 Pin Worms (Oxyuris equi)
 Bots (Gastrophilus spp)
 Thread Worms (Strongyloides)
 Eye Worm ( Thylozia Spp)

6. 1-Large Strongyle:
Large Strongyle are:
 Blood sucking of the large instestine
 Most dangerous parasite of horses
 Causes thromboembolic colic, various degrees of anemia.
Concept (Larvae live in artery supplying blood to the intestines. Blood clots form which
block blood supply to the intestine)

7. 2-Small Strongyle:
Small strongyle don’t migrate through the tissues, but burrow into the lining of the intestines
where they remain dormant or “encysted” for several months before completing their life
cycle.
Infection of small strongyles can cause:
 Severe damage to the lining of the intestines
 Colic and Diarrhea
 Weight Loss
 Slow growth in young horses
 Poor coat condition
 Lethargy

8. Large and small Encysted larvae in the large colon of a horse.

9. Control of strongyles:
 Broad spectrum anthelmintics like Ivermectin, Monoxidecin, Moxidectin,
Fenbendazole, Piperazine ( Only use in Small Strongyles) after every 6 months
 Avoid overgrazing pasture
 Use clean pastures for young animals
 Pile and compost manure

10. 3- Ascarids (Round Worms)
These parasites are most often a problem in young horses especially foals. Ascarids in large
numbers can cause bloackage ( impaction) of the intestines. Ascarid infection in young
horses can cause:
 Coughing
 Poor body condition and growth
 Rough hair coat
 Pot belly and colic
 Cause telescoping of intestine in foals
 Larvae migrate through lungs where they can cause pneumonia
 Interfere with digestion and absorption of nutrients, notably protein
Colic is most often seen the first time older foals (over three months of age)

11. Ascarid impaction and rupture

12. (Ascarids)

13. Control of Ascaids:
 Good sanitation
 Avoid putting foals in same pastures year after year
 Regular deworming of foals and young stock by Piperazine, broad spectrum
anthelmintics (Ivermectin, Moxidectin, Pyrantel pamoate, Fenbendazole,
Oxfendazole, Oxibendazole)

14. 4-Tape Worms (Anoplochephala)
Tape worms are known to cause colic, ranging from mild cramping to severe symptoms.
Horses are at risk when they consume this mite in grass, hay or grain.
Tapeworm infestations tend to occur where the small intestine enters the cecum. Horses
should be dewormed for tapeworms one to two times a year.
Tape Worm infection in young horses can cause:
 Cause colic
 IIeo-cecal valve damage
 Disrupt motility

16. Control of Tape Worms
The detection of Tapeworms is difficult on fecal exam. No drugs are approved for treating
tapeworms in the United States but Praziquantel and pyrantel can be used.

17. 5-Lungworms:
It cause chronic coughing in horses, Donkeys are the natural host of this parasites. Coughing,
lung irritation are the common signs. Ivermectin is the drug of choice for lungworms.

18. 6-Pinworms:
Lay their eggs on skin around the horses’s anus, creating an irritation that cause the horse to
repeatedly rub its tail, rat-tailed appearance. Pinworms can be controlled by cleaning of
stalls and by providing fresh food and water. Broad spectrum anthelmintics are used to treat
Pinworms.
Note: Pinworms in horses are not the same pinworm that children can get

19. 7-Bots:
They can damage the lining of the stomach where they attach. They can also cause ulceration
within the mouth where larvae burrow into the tissue after the eggs have been consumed. It
cause stomach irritation and colic. Ivermectin, Moxidectin are the drug of choice for Bots.
Mutual grooming leads to the
ingestion of bot eggs
gross lesion on stomach

20. 8-Threadworms:
They are mostly create problem in young foals, in which they cause diarrhea. Sanitation and
by keeping stall dry we can kill larvae of strongyloids.
To treat strongyloides deworming of mare should be done before foaling to prevent larval
migration to udder. Deworming should be done of foals at 4 weeks of age. Ivermectin,
Oxibendazole are the drug of choice for Thread worms.

21. Diagnosis of Internal Parasites:
 Fecal egg counts can be very helpful (negative fecal does not always mean no parasites)
 Monitor multiple horses on the farm at the same time
 Some parasites are difficult to diagnose like tapeworm, So for detection we use floating,
centrifuge, smear and Baermann Apparatus.

22. Dewormers:
No deworming product is 100% effective in riding the horse of all internal parasites.
However, it is necessary for a product to kill every worm in order to improve the horse’s
health, minimize the risk of serious disease, improve feed efficiency and reduce pasture
contamination with parasites eggs and larvae.

23. Designing a Deworming Program:
There are two basic types of deworming programs:
 1-Continuous:
Feeding a dewormer throughout the grazing season.
 2-Strategic:
Deworming only at certain times of the year or when fecal eggs counts rise.
The various deworming compounds each have benefits and weakness against different
parasites as well as a defined period of time when they are effective. The ideal program for
horse depends on the farm, pasture management and your geographic location.

24. Methods of Administration:
There are three ways to administer dewormers:
 Oral paste syringe
 Feed Additive (power, liquid or pellets dresses over the grain)
 Nasogastric (stomach) tube

25. A Complete Management Program:
 Keep the number of horses per acre to a minimum
 Dispose of manure regularly (at least twice a week for both dirt or sand yards).
 Do not spread manure on fields that are to be grazed by horses; compost it in a pile away
from the pasture.
 Keep in mind that Larvae can survive freezing temperatures but can not tolerate extreme
heat and drynsss.
 Keep foals and weanlings away from yearling to reduce exposure to ascarids and other
parasites.
 Use a feeder for hay and grain rather than feeding on the ground.
 Remove bot eggs regularly from the horses hair coat.
 Deworming should be done after every 2 month interval (6 times a year).

26.  Use a broad spectrum product as basis for control (Moxidectin).
 Be sure to treat for tapeworms 1-2 time per year.
 Avoid creating resistance to anthelmintics.
 Spread manure in hot weather away from fields where horses are grazing.
 Deworm new arrivals.

27. External Parasites of Equines:
 External parasites which are most common in Equines are
 Flies (Horse fly, Deer fly, Stable fly, Horn fly, Face fly, Bot fly, Black Fly)
 Biting midge
 Ticks (Hyalomma spp, Amblyomma spp, Horse ticks,)
 Mosquitoes
 Lice
 Mites

30. Some Problems due to External Parasites:
 Lyme disease
 Rocky Mountain Spotted Fever
 Psoroptic Mange
 Tick Fever
Horse bot fly eggs

31. Psoroptic Mange

32. Fly Control:
 The best way to prevent external parasites is to practice proper sanitation in your animal’s
pens and barns. For example, properly dispose of decayed wood shavings, vegetation,
manure, garbage and dead animals. Routinely drag pastures to scatter manure , this will
dry out the matter and discourage larval development. Proper drainage can also go a long
way in reducing the production of gnats, mosquitoes, horseflies, and deerflies. It also
helpful to apply a periodic insecticide application around the premises.
 Sprays, fogs, powders, granules, and baits introduce insecticides into the animal’s
environment to kill immature and adult stages of arthropods, especially fleas and ticks.
Environmental control is more effective in controlling fleas and one species of tick than
applying insecticides on animals

33.  Insecticides are applied to animals either by hand-application or self-treatment methods.
Hand-application methods include: dip, spray, dust, pour-on, spot-on, injection, and oral.
While many of these methods are seen less often in horse care, it is important to be aware
of them. Devices used for self-treatment methods are back rubbers, dust bags and tubes,
liquid wicks, neck collars, and ankle collars. Self-treatment devices, when properly used,
are more efficient at controlling hornflies than hand-application methods.

35. Some common Antiparasitic:
Generic Name Dose Rate Route
Albendazole 5-10mg/kg Oral
Fenbendazole 5-7.5mg/kg Oral
Mebendazole 10-15mg/kg Oral
Niclosamide 50-100mg/kg Oral
Piperazine 200-300mg/kg , 10-20ml/ 30kg Oral
Praziquantel 7.75%-12.5% 2.5mg/kg Oral , IM
Pyrantel 6.6mg/kg Oral
Tetramisole 15mg/kg Oral
Rafoxanide 7.5mg/kg Oral
Ivermectin 10mg/50kg Oral
Oxfendazole 5mg/kg Oral
Moxidectin 0.4mg/kg Oral
Doramectin 200mg/kg IM/SC
Levamisole 7.5mg/kg Oral
Oxyclozanide 10-15mg/kg Oral

36. Products available in PAK Markets:
Product name Packing Formulation Dose Rate Route
Equitak (Paste) 30ml Tube Abamectin,Praziquantel 5ml/100kg Oral
Valbazen 30ml, 1Litre Albendazole 5-10ml/100kg Oral
Albacon 10% 100ml,500ml,1L Albendazole 7.5ml/100kg Oral
Oxfendacon 100ml, 1Litre Oxfendazole 1ml/2.2kg Oral
Zamec 50ml Ivermectin 0.5ml/25kg S/C
Zantel (Human Pre) 10ml, Tablets Albendazole 10ml Oral
Bomectin 225ml, 5Litre Ivermectin 1ml/20kg Pour On
Dectomax 20,50,200,500ml Doramectin 1ml/50kg IM/SC
IMec 10ml Ivermectin 1ml/50g SC
Brema Mectin 50ml, 250ml Ivermectin 1ml/50kg SC
Levox Bolus 10, 50 Bolus Box Levamisole,Oxyclozanide 1B/100-150kg Oral
Primisole 50,100,1000g Levamisole Hydrochloride 1g/2-3L in 12 Hour Oral
Vety Alben 100ml, 1L, 2.5L Albendazole 15ml/50kg Oral
Duracure 10,50,100ml Doramectin 1ml/50kg IM/SC

43. Finally The End !!
Any Question