Revision of PGE

Question 1

What parasite is primarily responsible for causing PGE in sheep in the UK?

Answer 1

Telodorsagia Circumcinta

Question 2

What parasites of the abomasuem have a cervical papillae at the head end of the worm?

Answer 2

Haemonchus contortus and telodorsagia circumcinta

Question 3

What SI intectine parasite is coiled?

Answer 3

Cooperia spp

Question 4

What parasite has a charecteristic ‘notch’ at the head end of the worm?

Answer 4

Trichostronylus spp

Question 5

What is the typical length of a GI nematode egg?

Answer 5

90um

Question 6

What parasite is found in the LI is 5-6cm long and divided into a long hair like anterior region and a shorter thicker posterior region. Has distinctive yellowins ‘lemon’ shaped eggs

Answer 6

Trichuris spp adult female worms

Question 7

What GI parasite causes disease in young lambs in may?

Answer 7

Nematodirus battus

Question 8

What stage of haemonchus contortus is responsible for causing anaemia in lambs?

Answer 8

Adults

Question 9

How does PGE effect lambs?

Answer 9

Depressed apetite which reduces feed intake and growth rate

Permanent damage to the gut which reduces the absorption of nutrients and causes diarrhoea

Impaired mineral retention causing a small skelton

Reduced protein metabolism reducing muscle growth and carcase quality

Question 10

What are the clinical signs and sub-clinical signs of PGE?

Answer 10

Clinical

• Profuse watery diarrhoea
• Weight loss
• Inappetance
• Dehydration
• Death

Sub-clincal

• Poor weight gain
• Reduced appetite
• Reduced feen intake
• Loss of plasma proteins into GI tract

Question 11

How is PGE diagnosed?

Answer 11

Clinical signs

Diagnosis

FEC- over 750 EPG

Question 12

What worms that cause PGE in sheep are found in the abomasum, small intestine and large intestine?

Answer 12

Abomasum- Haemonchus contortus, telodorsagia circumcinta, trichostrongylus axei

Small intestine- Nematodirus spp, Trichostrongylus spp, Cooperia

LI- chabertia spp, Oesophagostomum spp, Trichuris spp

Question 13

What is the pre-patent period of trichostrongylus spp?

Answer 13

3 weeks

Question 14

When do telodorsagia circumcinta hypobiose?

Answer 14

In the abomasum as L4

Question 15

What factors influence epidemiology of PGE?

Answer 15

Source on infection- PPR, Hypobiosis of larvae, Overwinterted L3

Development and survival of free living stages is key- Development of eggs to L3 in envrionment, survival of L3 on pasture

Host susceptiblity

Question 16

When is the PPR rise of eggs from ewes?

Answer 16

PPR from Jan to May/June

Question 17

When do overwintered L3 graudually die by?

Answer 17

June

Question 18

When does amount of L3 peak?

Answer 18

Mid July

Question 19

What is the name for the barbers pole worm?

Answer 19

Haemonchus Contortus

Question 20

What is the pathogenesis of Haemonchosis?

Answer 20

Adults are voracious blood feeders
Erosion of the abomasal wall
Severe haemorrhagic gastritis
Severe anaemia
Oedema
Weight loss

Question 21

How can anaemia be best assed in sheep?

Answer 21

Animals eyelids

Question 22

Describe the epidemiology of Haemonchus?

Answer 22

L3 cannot over winter

PPR from ewes is main source of pasture contamination

Outbreaks in late summer

Question 23

How can haemonchus be diagnosed?

Answer 23

Clinical signs- anaemia

Season
Feacal egg counts

Question 24

What parasite often looks like cotton wool?

Answer 24

Nematodirus battus

Question 25

Describe the pathogenesis of Nemarodirus battus?

Answer 25

Developing L5 destroy mucosa

Catarrhal enteritis

Villous atrophy

Fluid and nutrient absorption disrupted

2000 worms can cause clinical disease

Question 26

What are the clinica signs of Nematodirus battus?

Answer 26

Sudden explosive outbreaks of acute, watery diarrhoea

Inappetence and dehydration

Abdominal pain, weight loss

Disease in lambs 4-12 weeks

Disease often starts in PPP

Over 500 heavy infestation

Question 28

Describe the epidemiology of Nematodirus battus?

Answer 28

L3 develops in egg over summer
Overwintered as larvated egg
Requires specific hatching requirments- exposure to prolonged period of chill, exposure to mean temp of 10 degrees

Question 29

When is the peak of L3 on pasture for nematodirus battus?

Answer 29

Emergence en masse in the spring