Parasitology - Exam 1 Lectures 1 --> 3 Flashcards
What is myiasis? What causes the different stages of myioasis?
- Myiuasis is the infestation of the larval stage of the fly (AKA **fly strike)
- Blowflies ** –> cause facultative myiasis where a specific host is NOT required and even a dead host can be used
- Note that there is an EXCEPTION WITH screwworms since they cause obligate myiasis
- Bots cause obligate myiasis where a specific host is required to reproduce
With regards to arthropods, discuss how this is broken donw
Main categories include insects and arachnids
- insects: flies, lice, and fleas
- arachnids: mites and ticks
With regards to blowfly miasis, what is the treatment for sheep vs dogs?
Clip and clean the area, remove the maggots mechanically:
- Sheep: organophosphates, macrocyclic lactones, spinosad are effective; apply directly to the affected region
- Dogs: Administer nitenpyram orally; apply insecticides like topical macrocyclic lactones
Whats the species that causes blowfly myiasis? Discuss this disease
Screwworms, known as cochliomyia hominivorax cause obligate myiasis and eats the lioving tissue. This is a reportable foreign animal disease
Regarding flies, what is myiasis and what flies are inbcluded in this?
- 1) Blowflies (AKA bottle flies)
- 2) Bot flies
- Both bloth flies and bot flies causes myiasis
Myiasis is when the larval stage of the fly causes damage to the animal host
what is the lifecycle for blowfly myiasis
What is the ‘fly strike’ in regards to blowfly myiasis
Blowfly myiasis - fly strike –> infestation with the larval stage
- warm, wet, soiled, smelly things attract blowflies
Discuss the progression of the fly-strike in regards to blowfly myiasis
What are some prevention methods for blowfly myiasis
- Sanitation - enviornmental and animal
- Crutch (remove woool from back legs and tail) and dock (shorten tail) sheep
- Treat primary causes of diahhrea: 1)internal nematode parasite control and 2) coccidiosis control
- get rid of adult flies
Discuss screwworms
- cochliomyia hominivorax known as screworms
- a special blowfly that causes obligate myiasis that eats a living tissue
- reportable foeign animal disease
what is the lifecycle of screwworms and discuss the progression of it
1) Larcae feed on the healthy tissue in and around the world
2) Massive tissue destruction:
- swecondary effects: A) secondary blowefly strike B) bacterial infection C) death
discuss the treatment for screworms
Treatment –> clip and clean around the wound
- apply insecticide
- Nitenpyram
Discuss the specific genus of bot flies for each species
-
- hypoderma sp –> Cattle
- Oestrus ovis –> sheep
- Gastrophilus sp –> Horse
- Cuterebra –> rodents, dogs and cats
All of these are species of Bot flies
Bot flies: do not feed (during the adult stage), only reproduce
what is the difference between bot flies asnd blow flies
Bot flies are different from blow flies because bot flies cause an obligate myiasis
Discuss the lifecycle of Bot flies
Discuss the life cycle of bot flies, specifically the hypoderma species
Hypoderma –> warble flies, cattle grubs, heel flies, gadlies (these all refer to hypoderma of the cattle
adult fliy lays eggs on cattle hairs > larvae penetrate skin > migrate to back > emergy and fall to ground to pupate
Life cycle:
- June –> July: adults emerge and lay eggs on the front legs of cattle. Eggs hatch, and larva penetrate the skin
- August –> December: Larva migrate though submucosa and grow as they migrate
- January-February: bots accumulate around esophogus and spinal cabnal and form ‘warbles’ on the back
- March –> May: Bots fall to the ground and pupate
-
Botv flies: Hypoderma species –> discus the effects on the host
**Worry –> ** flies bother cattle to the poont where they dont graze properly resulting in poor growth and poor production
**Meat and hide damage: **results in something called Butchers jelly
Discuss the treatment for the hypoderma species of bot flies
- Macrocyclic lactones are highly effective –> Ivermectin, eprinomectin, moxidectin
- Timing of treatment is cruical –> Treat as soon as possible after adults lay eggs in the fall
- do NOT treat after January
What is the proper name for the Bot flies, specifically the sheep nasal bot. ALso discuss its lifecycle
- ## Oestrus ovis –> Sheep nasal bot
What are the effects on the host of the sheep Nasal Bot (Bot flies)
- Summer sheep hiding noses
discuss the effects, diagnosis, and treatment for Oestrus ovis, the sheep nasal bot
- Minor mucosal irritation from the larva –> usually asymptomatic
- Diagnosis: Direct observation of larvae (usually found in water troughs)
; no specific clinical signs (mild upper respiratory tract signs
Treatment - Macrocyclic lactones very effective but usually not necessay
What is the proper name for the horse bot fly (Bot flies) and also discuss its lifecycle
- ## Gastrophilus
For Bot flies (gastrophilus), discuss the effects on the host, diagnosis, and treatment
- Effects on host: usually asymptomatic; ulceers at site of attachment
- Diagnosis: infection is usually assumed (confirmed via endoscopy); can find eggs on the fur and larvae on the mouth
- Treatment: Macrocyclic lactones in the fall
what is the proper name for the rodent bot fly (bot flies)
- Cuterebra
- life cycle is missing along with effects on the host, treatment, and diagnosis
