Clinical cattle parasitology 1 + 2 Flashcards

(79 cards)

1
Q

List 3 abomasal nematodes of cattle

A

Haemonchus contortus
Ostertagia ostertagi
Trichostrongylus axei

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

List 3 Small intestinal nematodes of cattle

A

Trichostrongylus spp
Nematodirus
Cooperia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Name 3 large intestinal nematodes of cattle

A

Oesophagostomum
Chabertia
Trichuris

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe the pathogenesis of ostertagia

A
  • Abomasal wall damage
  • Raised pH of gastric juice from 2 up to ~7
  • Poorer digestion bacterial overgrowth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe the pathogenesis of Cooperia

A

Damage to intestinal mucosa
Impaired absorption of nutrients and water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which animals are affected by PGE in cattle?

A
  • First season dairy heifers
  • Autumn born suckler calves
  • Spring born suckler calves
  • Immunity acquired over 1-2 grazing seasons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How is PGE in cattle diagnosed?

A
  • Grazing history & signalment
  • Clinical signs and seasonality
  • Plasma pepsinogen- ostertagiosis
  • Faecal egg counts
  • PM
  • Antibody ELISA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which diagnostic test is not useful for type 2 ostertagiosis?

A

Faecal egg counts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Name the lungworm of cattle

A

Dictyocaulus viviparous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the live cycle of Dictyocaulus

A

L1 larvae passed in faeces
Develop to L3 in the faecal pat
Infective larvae spread onto pasture
Larvae ingested and then migrate to lungs
L3 develop into adults in the lung tissue
Eggs produced
Eggs hatch and L1 larvae are coughed up and swallowed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe lungworm survival on pasture

A

Short
After 6 weeks, pasture can be considered ‘clean’ again
Larvae not necessarily present at turnout

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the most important source of Dictyocaulus each year?

A

Carrier animals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Is the pattern of disease easier to predict in GIT nematodes or lungworms?

A

GIT nematodes - consistent, predictable annual disease pattern

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe the epidemiology of Dictyocaulus

A
  • Geographic variation of distribution
  • Associated with wet summers and rainfall: dispersal from faecal pats
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the prepatent phase of a Dictyocaulus infection

A

L4 larvae in alveoli - migrate towards to bronchi
- Alveolitis, bronchiolitis, bronchitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the patent phase of a Dictyocaulus infection

A

Adult worms in larger airways, eggs and L1 larvae in alveoli
- Obstructive bronchitis
- Aspiration pneumonia
- Secondary bacterial infections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the clinical signs of a mild Dictyocaulus infection?

A

Intermittent cough when exercised

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the clinical signs of a moderate Dictyocaulus infection?

A

Frequent cough at rest
Laboured breathing
Squeaks/crackles on auscultation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the clinical signs of a severe Dictyocaulus infection?

A

Severe tachypnoea
Dyspnoea
Air hunger position
Mouth breathing
Deep, harsh cough
Salivation, anorexia
Death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How is a Dictyocaulus infection diagnosed?

A
  • Signalment, history & clinical signs
  • Post-mortem
  • Baermann for L1 larvae
  • Antibody ELISA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Name the liver fluke species of cattle

A

Fasciola hepatica

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Describe the life cycle of liver fluke

A
  1. Eggs shed in faeces
  2. Miracidium hatch out of the eggs after 2-4w
  3. Migrate into the mud snail
  4. Cercariae are shed from the mud snail
  5. Become metacecariae on pasture where they are viable for several months
  6. Ingested by cattle where they migrate to the liver
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

When are the levels of metacecariae on pasture the highest?

A

Autumn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

When are the levels of metacecariae on pasture the lowest?

A

Summer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Which species are hosts of fluke?
Cattle and sheep cant co graze
26
Describe a 'flukey' pasture
- Any area of wet or boggy ground - Standing water, rushes etc. give clues - Agri-environment schemes with wetland habitats
27
Describe the pathology and clinical presentation of acute fluke disease
- 2-6 weeks post-infection - Juvenile flukes migrating through liver parenchyma - Tissue damage and haemorrhage - Uncommon in cattle- young calves with heavy challenge
28
Describe the pathology and clinical presentation of chronic fluke disease
- 10-12 weeks+ post-infection - Adult flukes within bile ducts - Chronic anaemia, hypoalbuminaemia (“bottlejaw”) - Weight-loss & poor BCS
29
Describe the pathology and clinical presentation of a sub-clinical fluke disease
Very common Ongoing losses with growth/ milk-yield/ reduced fertility etc.
30
List the methods available to diagnose fluke
- Signalment, history & clinical signs - Serum biochemistry: Serum albumen, GLDH & GGT - Fluke egg sedimentation - Copro-antigen ELISA - Antibody ELISA - Forecasting - Post mortem
31
Describe fluke egg sedimentation as a diagnostic method
- Individual or composite samples - Patent infections only (12 weeks+) - Relatively low sensitivity
32
Describe antibody ELISA as a diagnostic method
- 2-4 weeks post-infection - Serum or milk samples - BMT samples indicate >25% herd infected - Exposure, not infection (consider treatment history)
33
How can fluke be controlled?
- Forecasting - Plan strategy in advance - Identify at risk animals - Perform egg counts - Move to safe pastures
34
How can anthelmintics be used strategically against fluke?
- Keep pasture contamination low in the early part of the season - Can reduce treatment later in the season as overwintered larvae die off
35
How can anthelmintics be used therapeutically against fluke?
- Treat in response to disease monitoring - Rotate grazing from early in the season
36
Name 3 benzimidazoles
Albendazole Fenbendazole Triclabendazole
37
What colour drench are benzimidazoles?
White drenches
38
Which benzimidazole treats fluke but not lungworm?
Triclabendazole
39
Levamisole can be used to treat which parasites?
Nematodes Lungworm - not fluke or tapeworm
40
Name 4 macrocytic lactones
Ivermectin Doramectin Moxidectin Eprinomectin
41
Macrocytic lactones can be used to treat which parasites?
Nematodes Lungworm - not fluke or tapeworm
42
What colour drench are macrocytic lactones?
Clear
43
Describe strategic dosing for PGE
Ivermectin pour on - 14d residual activity 3 - 8 - 13w dosing schedule Turnout in April - dose 3 weeks later, then 5 weeks after that, then repeat 5 weeks later
44
How long is the residual activity of Doramectin?
5 weeks
45
When is lungworm vaccination reccomended?
If there is a history of disease on the farm
46
Describe the lungworm vaccine and its schedule
Irradiated L3 larvae (live vaccine) - Calves >8 weeks old - 2 doses, 4 weeks apart - 2nd dose 2 weeks before turnout Subsequent natural exposure is essential for full immunity to develop…
47
Describe how to treat animals with clinical lungworm disease
- Treat all animals in the effected group - Move clinically affected animals to safe pastures or house (well ventilated building) - Treat with long-acting group 3-ML if not able to move - Check for secondary infections - Antibiotics and NSAIDs possible indicated
48
What should be considered when timing fluke treatment?
Treat housed animals with adulticides Reduce selection pressure on TCBZ Consider milk-withdrawal for lactating animals Treat during dry period
49
Which drug treats all stages of fluke?
Triclabendazole - but high resistance
50
Name 2 other drugs that can be used against fluke
Albendazole Closantel
51
What are the reasons for quarantine treatments?
Avoid introduction of new parasites Avoid introduction of drug resistance COWS guidelines to reduce likelihood - Combination treatments - Holding animals off pastures
52
For fluke how would you check treatment has been affected?
Day 0 egg count Compare to an egg count 21d post treatment - ideally a more than 95% reduction
53
Name the COWS 5 Rs
The right product for the type of worm The right animal The right time The right dose rate Administered in the right way
54
Which animals are affected by cryptosporidium?
Young calves 14-21do
55
How does cryptosporidium present?
Diarrhoea and dehydration
56
How is cryptosporidium diagnosed?
History & clinical signs Faecal smears: Ziehl-Nielsen staining Pen-side antigen test strips
57
How is cryptosporidium treated?
- Good hygiene practice: Disinfection of pens & feeding equipment - Reduce stocking density - Halofuginone: prophylaxis and reduces symptoms in clinical cases - Supportive treatment: IVFT
58
What type of drug is halofuginone?
Coccidiostat - works against protozoa
59
Which animals are at risk of coccidiosis?
Young animals
60
Where are coccidiosis pathogens found?
Housed and grazing animals Replicate in the caecum and colon
61
Describe the clinical signs of coccidiosis
Bloody dysentery and tenesmus Chronic wasting/ poor appetite
62
How is coccidiosis diagnosed?
History and clinical signs Postmortem and histopathology Oocysts (Wet smears or McMaster)
63
How is coccidiosis treated and controlled?
- Reduce environmental contamination: all-in all-out with cleaning and disinfection - Prophylactic treatment - Treatment: Toltrazuril & Diclazuril
64
Which pathogen of cattle is identified in 25% of abortion cases?
Neospora
65
Describe the hosts of neospora
- Dogs are the definitive host - Cattle are the intermediate hosts
66
Describe the life cycle of neospora
- Dogs pass oocysts in faeces which contaminate pasture - Ingested by a cow (can affect foetus if infected) - Infected carcass or placenta ingested by dog
67
What are the 3 outcomes for a calf if a cow if infected with neospora when pregnant?
- Birth of a healthy uninfected calf - Birth of a persistently infected calf - Aborted or premature calf
68
How is neospora caninum prevented/controlled?
- Keep a closed herd: don't buy in any replacement stock - Dispose of cattle tissues left over from a calving, or aborted foetuses, in a safe and timely manner. - Prevent dogs from having access to calving areas or parts of the farm where pregnant cattle are kept. - Deny dogs access to areas where cattle feed is kept or fields that are used for grazing to prevent dog faeces. - Signage on public footpaths.
69
How can serum antibody testing be used to control neospora infections?
- Ideally 12-4 weeks pre-calving (recrudescence) - Serum sampling of calves pre-colostrum for evidence of vertical transmission - If positive, do not breed from mother or calf again - False negatives may occur
70
Name 3 biting/nuisance flies of cattle
Hydrotea irritans Muscidae Culicoides
71
Name the condition caused by Hydrotea irritans
Summer mastitis
72
How are biting/nuisance flies in cattle controlled?
Spot-on/ pour-on synthetic pyrethroids Tail bands/ ear tags Pasture management & breeding habitat
73
When are mite/lice infections most common in cattle?
Over winter in housed animals
74
Name 3 mite species of cattle
Chorioptes bovis Psoroptes bovis Sarcoptes scabei
75
Name a chewing and sucking louse of cattle
Chewing = Bovicola Sucking = linognathus
76
Ixodes ricinus is a vector of? (3 possible)
Babesiosis Anaplasmosis Louping ill
77
Compare treatments for chewing vs sucking lice
Pour-ons for chewing lice Injectables for sucking lice
78
Name the rumen fluke parasite
Calicophoron daubneyi
79
Calicophoron daubneyi has the same intermediate host as which parasite?
Fluke - Galba truncatula