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| [[Image:Horse Bot Fly.jpg|thumb|right|150px|Horse Bot Fly - Dennis Ray - Wikimedia Commons]] | | [[Image:Horse Bot Fly.jpg|thumb|right|150px|Horse Bot Fly - Dennis Ray - Wikimedia Commons]] |
| *Also known as the horse bot fly | | *Also known as the horse bot fly |
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| + | *Obligate parasites of equids |
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| + | *Spend most of lifecycle in equine stomach |
| + | **Cause little pathogenesic significance |
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| + | *Three important species (in the UK) |
| + | **''G. intestinalis'' which is the most common |
| + | **''G. nasalis'' |
| + | **''G. haemorrhoidalis'' which is rare |
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| + | *Two other important veterinary species |
| + | **''G. nigricornis'' |
| + | **''G. inermis'' |
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| '''Recognition''' | | '''Recognition''' |
| + | *Medium to large flies at 10-20mm long |
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| + | *Look similar to drone bumble bees |
| + | **Body covered with dense yellow hair |
| + | **Dark coloured hairs produce a banding pattern |
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| + | *Clear wings with brown patches |
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| '''Life Cycle''' | | '''Life Cycle''' |
| + | *Adults are most active in late summer |
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| + | *Eggs hatch spontaneously or are stimulated to hatch through an increase in warmth and moisture from the animal self-grooming |
| + | **''G. intestinalis'' |
| + | ***Creamy-white eggs |
| + | ***1-2mm in length |
| + | ***Eggs laid in the hair of the shoulders and fore legs |
| + | **''G. nasalis'' |
| + | ***Eggs laid in the intermandibular area |
| + | *''G. haemorrhoidalis'' |
| + | ***Eggs laid around the lips |
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| + | *Larvae crawl into the mouth and penetrate the tissues of the buccal mucosa which takes a few weeks |
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| + | *Larvae then emerge and are swallowed |
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| + | *Larvae pass into the stomach and attach to the gastric mucosa |
| + | **Larvae are now known as '''bots''' |
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| + | *Each species attaches to a specific part of the stomach |
| + | **''G. intestinalis'' attaches to the cardiac region |
| + | **''G. nasalis'' attaches to the pylorus |
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| + | *After 10-12 months in the stomach, the larvae detach and are passed out in the faeces |
| + | **''G. haemorrhoidalis'' attaches to the rectal mucosa before being passed out |
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| + | *Larvae pupate on the ground |
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| + | *Adults hatch after 1-2 months and survive for a few days up to two weeks |
| + | **Adults have non-functional mouthparts so cannot feed |
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| + | *There is only one generation per year in temperate regions of the world |
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| '''Pathogenesis''' | | '''Pathogenesis''' |
| + | *Adult cause annoyance when egg laying |
| + | **Disturbance and panic can ensue |
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| + | *Larvae cause a marked inflammatory reaction when attached to the gastric mucosa |
| + | **Ring like thickening around the base of each attached larvae |
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| + | *Large numbes of larvae may interfere with the passage of food and action of the sphincters |
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| + | *''G. haemorrhoidalis'' can cause mild irritation to the rectal wall |
| + | **Host reaction to larvae in the mouth is minimal |
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| '''Control''' | | '''Control''' |
| + | *Treatment of horses with [[Ectoparaciticides|insecticides]] over winter |
| + | **Breaks the life cycle as all the population are present as bots in the stomach |
| + | |
| + | *If eggs are present in late summer, the horse's coat can be sponged with an [[ectoparasite|insecticide]] |
| + | **Stimulates hatching |
| + | **Kills larvae |
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| ===''Dermatobia hominis''=== | | ===''Dermatobia hominis''=== |