1. Ectoparasites

2. The Arthropods Phylum Arthropoda Class Insecta Class Arachnida Class Pentastomida

3. Class insecta Class Insecta Order Diptera (flies) Order Phthiraptera (lice) Order Siphonaptera (fleas)

4. Class Arachnida Ticks and mites are small arachnids in the Order Acarina. Many are parasitic on animals and humans, & vary greatly between families. Ticks and mites are small arachnids in the Order Acarina. Many are parasitic on animals and humans, & vary greatly between families.

5. Class Pentastomida (“tongue worms”) Very unusual insects, may be related to sarcoptiform mites or to annelids (earthworms). Very unusual insects, may be related to sarcoptiform mites or to annelids (earthworms).

6. Parasite Species Agent Disease ParasiteSpeciesAgentDisease MosquitoesCulicoidesMitesFliesHorseVirusVirusVirusCestodeNematodeWNV WEE; EEE; VEE EIATapeworms Summer sores (habronema) VirusEIA

7. Bot fly Female bot flies lay from 150 to 1,000 yellowish eggs. The eggs are firmly glued to the hairs of the forelegs, belly, flanks, shoulders and other parts of the body of the horse. While the fly's egg laying does not cause the horse pain, the horse often is bothered by presence of the fly. Female bot flies lay from 150 to 1,000 yellowish eggs. The eggs are firmly glued to the hairs of the forelegs, belly, flanks, shoulders and other parts of the body of the horse. While the fly's egg laying does not cause the horse pain, the horse often is bothered by presence of the fly. Bee-like adult

8. Bot flies Does not bite; may bother Does not bite; may bother Eggs on legs Eggs on legs Licked by horse Licked by horse 4 weeks in oral mucosa 4 weeks in oral mucosa Overwinter in stomach Overwinter in stomach Ulcers Ulcers Control: Control: – External: insecticide on legs – Internal: broad spectrum anthelmintics

9. Horse and deer flies Large Large Multiple species Multiple species Females only bite Females only bite Generally: larvae in water or Generally: larvae in water or damp locations Strong flyers Strong flyers Daytime feeders Daytime feeders Painful bites Painful bites – Horse flies: anti-coagulant – Secondary infections – Transmission of disease: EIA EIA Anaplasmosis Anaplasmosis Larvae – not possible Larvae – not possible Adults – fly repellants Adults – fly repellants

10. Stable flies Both males and females Both males and females Around premises Around premises Strong flyers Strong flyers Painful bites Painful bites Soggy hay/manure hay Soggy hay/manure hay Transmit Transmit – EIA – Habronema Identify and control Identify and control breeding site(s) Insect repellants Insect repellants

11. Summer sores (habronemiasis) Caused by the larva of nematode species; Caused by the larva of nematode species; Habronema muscae Habronema majus Stomach-dwelling Stomach-dwelling Indirect life cycle Indirect life cycle Fly-transmitted Fly-transmitted Seasonal Seasonal Hypersensitivity component Hypersensitivity component “Aberrant parasitism” when “Aberrant parasitism” when larvae deposited in wounds Esp. eyes, conjunctiva, male Esp. eyes, conjunctiva, male genitalia, distal limbs Prevent - ivermectin Prevent - ivermectin

12. Culicoide Hypersensitivity ( Queensland itch, Sweet itch, Summer itch)

13. Culicoides hypersensitivity “Sweet itch” “Sweet itch” Individual horses Individual horses Acute hypersensitivity Acute hypersensitivity Spring-summer Spring-summer Regresses in fall- winter Regresses in fall- winter Tail, rump, back, withers Tail, rump, back, withers

14. No-See-Ums Culicoides & sandflies Culicoides & sandflies Need aquatic habitats Need aquatic habitats Allergic reactions in Allergic reactions inhorses Also: Also: – BTV bluetongue virus – EHD epizootic hemorrhagic disease – EIA

15. Mosquitoes Wet sites Wet sites Only females feed Only females feed Still water Still water 6 – 7 days to complete life 6 – 7 days to complete lifecycle Day or night feeders Day or night feeders Variable year to year, Variable year to year, depending on moisture Many species Many species Diseases: Diseases: – WEE – EEE – WNV – VEE

17. Mosquito control Control large wet breeding sites Control large wet breeding sites – Pest control districts Keep water containers to minimum: Keep water containers to minimum: – Empty troughs every ~3 days Bacillus thuringensis (BT) dunks Bacillus thuringensis (BT) dunks Screen water containers Screen water containers Stable horses dawn and dusk Stable horses dawn and dusk Insect zappers relatively ineffective Insect zappers relatively ineffective Topic sprays for horses Topic sprays for horses

18. Topical anti-mosquito products Pyrethrins - chrysanthemum extract Pyrethrins - chrysanthemum extract – Effective; short duration Pyrethroids - synthetic Pyrethroids - synthetic – Low toxicity; longer-lasting than pyrethrins. – Permethrin and cypermethrin Plant extracts Plant extracts – Citronella, eucalyptus, pennyroyal, cedar, geraniol etc. DEET (N,N-Diethyl-meta-toluamide, is the most common active ingredient in insect repellents) DEET (N,N-Diethyl-meta-toluamide, is the most common active ingredient in insect repellents) – Now EPA approved for horses – Licensed veterinarians. – Repellent only - not insecticidal

19. Blowflies and fleshflies 60 species 60 species Cadavers and wounds Cadavers and wounds Eggs in moist wool, Eggs in moist wool, open wounds or break in the skin Rare in cattle or horses. Rare in cattle or horses. Painful – can be fatal Painful – can be fatal Prevent by proper Prevent by proper insecticide treatments. insecticide treatments. Treat with insecticide Treat with insecticideapplications

20. Screwworm New World species New World species Infects live warm blooded species Infects live warm blooded species Infects people Infects people Open wounds and healthy tissue Open wounds and healthy tissue Eradicated in US Eradicated in US Esp. newborns Esp. newborns High mortality when untreated High mortality when untreated Latin America Latin America Controlled by sterile male release Controlled by sterile male release Reportable to USDA Reportable to USDA Periodic incursions to USA Periodic incursions to USA

21. Horn flies Blood suckers Blood suckers Eggs in fresh manure (<10 min) Eggs in fresh manure (<10 min) Consume 10μl blood daily Consume 10μl blood daily – 3000/cow=30 ml/day Rapid life cycle (10 days) Rapid life cycle (10 days) Strong flyers Strong flyers Live on cattle Live on cattle Nuisance: Nuisance: – Cattle – Horses Insecticidal ear tags Insecticidal ear tags – On host a lot Dragging pastures to break up feces Dragging pastures to break up feces

22. Acute hypersensitivity reactions in horse

24. Lice Sucking – blood Biting – surface debris Biting – surface debris Location specific Location specific Whole life on host Whole life on host Winter Winter Attack all ages esp. Attack all ages esp. Head, neck, shoulders, Head, neck, shoulders, and rump Irritate skin Irritate skin Control in fall Control in fall Pour-on formulations – Pour-on formulations – treat twice 3 weeks apart *Zoonotic

25. Mange mites Now uncommon Now uncommon Burrow in skin Burrow in skin Dermatitis and Dermatitis andhypersensitivityreactions Transmission by: Transmission by: – Direct contact – Fomites Ivermectin Ivermectin Decontaminate stables Decontaminate stables and grooming equipment

26. Demodectic Mites The demodectic or follicular mite is a microscopic (0.23mm), cigar shaped worm-like mite that lives within the skin. The demodectic or follicular mite is a microscopic (0.23mm), cigar shaped worm-like mite that lives within the skin. All stages of the life cycle are often found within the hair follicle and sebaceous glands. All stages of the life cycle are often found within the hair follicle and sebaceous glands. The mite causes nodular lesions in the skin usually around the neck and shoulders. The mite causes nodular lesions in the skin usually around the neck and shoulders.

27. Chigger Mites Chigger mites (redbugs) make up a large group of species which occasionally cause problems for both horses and man. They cause intense itching and reddish welts on the skin. Chigger mites (redbugs) make up a large group of species which occasionally cause problems for both horses and man. They cause intense itching and reddish welts on the skin.

28. Mite Control Mange control requires isolation of infested animals and thorough wetting of the whole animal with timed applications of approved pesticides. Mange control requires isolation of infested animals and thorough wetting of the whole animal with timed applications of approved pesticides. Chiggers can be controlled by application of detergent wash containing one of the insecticides registered for other mites. Area control is not feasible. Chiggers can be controlled by application of detergent wash containing one of the insecticides registered for other mites. Area control is not feasible.

29. Ticks Multiple species Multiple species Seasonal activity varies: Seasonal activity varies: winter vs. summer Some have multiple hosts, Some have multiple hosts, depending on stage Dermatitis Dermatitis Transmission: Transmission: – Anaplasmosis – Tularemia – Tick paralysis – Babesiosis (horses) Topical/systemic acaricides Topical/systemic acaricides

30. Spinose ear ticks feeding

31. External parasites horses Agent(s) Impact Disease Control Comment Stable fly Habronema ++ “Summer sores” Anthelmitic Summer Biting midges Culicoides ++ “Sweet itch” Stabling SteroidsSummerFlies (stable, house, horse, deer) + Annoyance Wounds Repellents Summer Stable fly

32. Major insecticide classes Class Example Notes Botanicals Pyrethrin family Ear tags Pyrethroid family Safe Organophosphates Tiguvon® (fenthion) Sprays Carbamates Ear tags Oral (some) Toxic! Formamides Amitraz Lice/ticks Fatal to horses DDT derivatives Methoxychlor Horses DustSprays

33. Keys To Pesticide Safety Before using any pesticide, stop and read the precautions. Before using any pesticide, stop and read the precautions. Read the label on each pesticide container before each use. heed all warnings and precautions. Read the label on each pesticide container before each use. heed all warnings and precautions. Store all pesticides in their original containers away from food or feed. Store all pesticides in their original containers away from food or feed. Keep pesticides out of the reach of children, pets and livestock. Keep pesticides out of the reach of children, pets and livestock. Apply pesticides only as directed. Apply pesticides only as directed. Dispose of empty containers promptly and safely Dispose of empty containers promptly and safely

34. References http://edis.ifas.ufl.edu/IG139 http://edis.ifas.ufl.edu/IG139 http://edis.ifas.ufl.edu/IG139