Small Ruminant Parisitology Flashcards Preview

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Flashcards in Small Ruminant Parisitology Deck (35)
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1
Q

Name 3 anti-parasitic drugs licensed for sheep in canada

A

Ivermectin
Lasalocid
Sulphamethazine

2
Q

Off-label anti-parasitic drugs

A

Fenbendazole • Decoquinate • Albendazole • (Monensin)

3
Q

Diarrhea

A

A. Coccidiosis

B. Parasitic gastroenteritis

4
Q

Pathogenic species in sheep (2)

A

2 pathogenic – E. crandallis, E. ovinoidalis

5
Q

Pathogenic species in goats (many)

A

E. ninakohlyakimovae, E. caprina, E. arloingi, etc

6
Q

Signalment for coccidiosis in sheep/goats

Clinical signs

A

very common
• typically lambs/kids @ 1-4 months of age
• usually poor growth, often pasty/diarrheic feces, dullness, abdominal pain, occasionally bloody diarrhea
• pot bellied, open fleeced
• subclinical infections → production impact
• often other diseases (e.g. pneumonia, urolithiasis)

7
Q

Diagnosis for coccidiosis in sheep/goats

A

Clinical signs + fecal flotation – speciate ?

8
Q

coccidia oocysts in the environment - how do they get there?

A

(a) oocysts may overwinter in environment
(b) ewes shed small #s oocysts in periparturient period
→ subclinical infections in early lambs → ?
• intensification ↑ likelihood of clinical coccidiosis
outdoors + indoors
• stress → disease (e.g. dietary change, weaning, shipping)

9
Q

Treatment for coccidia

A

Treatment – isolate clinically affected – fluid therapy?

- treat entire group with coccidiocide (sulfa, amprolium) - move to clean bedding/grazing

10
Q

Coccidia prevention

A

• good hygiene in barns – clean bedding, dry, feed off ground
• house/graze late lambs in different areas from early lambs
• coccidiostat in lamb creep feed until 90 days old or until market - lasalocid, decoquinate, monensin (!)
- correct dose ?
• if no creep feed – script decoquinate or lasalocid into mineral/salt mix
• coccidiostat to ewes for 30 days prepartum ? - lasalocid, decoquinate

11
Q

3 most important gastrointestinal nematodes (all live in the abomasum). Which cause diarrhea

A

Teladorsagia (similar to ostertagia)
Trhichostrongylus
Haemonchus (largest) - no diarrhea

12
Q

What causes sudden death?

A

Haemonchus

Fasciolosis

13
Q

Haemonchus

A

Sheep + goats – Haemonchus contortus (barber pole worm) Acute disease – sudden death, severe anemia
- lethargy, no diarrhea
Chronic disease – edema, weight loss, poor growth, anemia
Highest pasture L3 levels - late summer (July/August) Losses - lambs, yearlings (+/- adult sheep)

14
Q

Haemonchus - Diagnosis & PM

A

Diagnosis – anemia, hypoproteinemia,
- often high gastro-intestinal nematode (GIN) egg counts
PM – hyperemic abomasal mucosa + parasite #s 1 parasite = 50μl blood loss/day

15
Q

What is the immunity status of ewes w.r.t. gastroenteritis? lambs?

A

ewes = significant source of pasture contamination in spring (“peri-parturient relaxation of immunity”: 2-4 weeks before
lambing to 4-8 weeks after lambing)
primarily lambs mid summer onwards (+/- older animals)

16
Q

What are the concerns with parasitic gastroenteritis w.r.t. drug resistance

A

globally – drug resistance in Teladorsagia and

Haemonchus = major concern:

17
Q

Main things to remember

A

• ewes = primary source of pasture contamination in spring • prepatent period for important parasites = 3 weeks

18
Q

Goals of drug programs

A

• minimize drug use
• minimize pasture contamination to end of June (“Targeted
deworming”)
• ideally, only treat animals that require treatment (reduces risk of selection for drug resistance)

19
Q

Seasonal drug protocol for GI parasites

A

Autumn: Winter:
Deworm at housing with drug that kills adults & larvae
Winter: Sheep overwinter with few larvae and adults
Spring: On pasture, sheep eat infective L3. From infection to egg laying takes 21 days
Summer: Worming prevents pasture
contamination. Naive lambs produce most eggs so must be dewormed!

20
Q

Targetted GI parasite treatment

A

• Treat ewes at lambing if not treated in fall
• Monitor 4+ weeks after turnout
LSSC Ltd
• Monitor lambs at 4+ weeks after turnout and treat accordingly (if not possible, treat at 4 weeks and 8 weeks after turnout)
If control periparturient rise in ewe egg output – not usually necessary to dose lambs until weaning
• Treat in fall, at housing
MONITOR LAMBS IN JULY

21
Q

What is the famacha guide?

A

Looks for anemia by looking at the eyes and only treating those with red conjunctiva. It is only applicable in areas with only haemonchus (useful in the south)

22
Q

What type of lice is common in sheep?

A

Sheep - biting lice (damalina ovis)

23
Q

What type of lice is common in goats?

A

Damalina caprae

Linognathus stenopsis

24
Q

Clinical signs for lice

A

winter months
signs = pruritis, wool loss, decrease in weight, (anemia)
more severe if debilitated (malnutrition, GI parasitism)
Trasminitted through direct contact

25
Q

Treatment for lice

A

Permetrhin, carbaryl
2 treatments 10-14 days apart if non-residual
injectable ivermectin (only for sucking lice)

26
Q

Control for lice

A

shearing
preventative ttreatment in the fall
drug resistance - change drug class
quarentine treatment

27
Q

Melophagus ovinus is what?

A

sheep ked

28
Q

Melophagus ovinus is found when? life cycle is where/how long? tramsnission? what does it look like?

A

• winter months, poor condition
• entire 6-week life cycle on sheep/goats • transmission – direct contact
• pruritus, stained wool → fleece damage, anemia, odour, ↓ value
• shearing – removes larvae + pupae
hot climate – kills keds (remain ventral neck, breech)

29
Q

Treatment for kieds

A

as for lice - shearing, permethrin, carbaryl, injectable ivermectin

30
Q

Most common mange in cows & sheep?

A

chorioptic (tail head for cows, feet/scrotum for sheep)

31
Q

Clinical signs for chorioptic mange? Peak season?

A

Alopecia, erythema, crusts, pruritis - wooless areas

  • sheep scrotum, distal limbs
  • goats - lower limbs, abdomen, hindquarters
  • restless, chew on feet
  • temporary infertility in rams?
  • chorioptes ovis - host specific, peak in winter months.
32
Q

Chorioptic mange - transmission?

A

Transmission - direct contact
live off host for a few days
Life cycle = 2-3 weeks
Diagnosis: skin scrapings at the edge of the lesions
Treatment: permetrhin pour on , repeat 10 days (ivermectin doesn’t work well)
Note psoroptic manage is very uncommon in Canada & notifiable

33
Q

What is the nasal bot?

A

Oestrus ovis (nasal myiasis)

34
Q

How do sheep get infected by nasal bots

A

fly deposits larvae around/in nostrils in fluid → dorsal turbinates, sinuses (weeks – months) → pupate in ground (in spring)
• initial infestation → no signs
• subsequent infections → hypersensitivity
Clinical signs:
• fly → head shaking, nose rubbing, feet stomping
• larvae → rhinitis, sneezing, mucopurulent nasal discharge • production losses ?
Goats – usually milder clinical signs than sheep - usually with infected sheep
Diagnosis – nasal discharge – numerous eosinophils + mast cells
- season

35
Q

Treatment for nasal bots (oestrus ovis)

A

IVermectin SC or PO

WInter treatment will kill over-wintering larvae