Reproductive pathogens (Cattle)

Question 1

What is metritis?

Answer 1

Inflammation of the whole uterus caused by bacterial infection

Question 2

What are the clinical signs of metritis?

Answer 2

Reddish-brownish foul smelling uterine exudate ± fever

Question 3

What are the 3 main pathogens involved/causing metritis?

Answer 3

• Escherichia coli
• Fusobacterium necrophorum
• Trueperella pyogenes

Question 4

When is E.coli particularly prevalent in metritis?

Answer 4

In the first week postpartum

Question 5

Which toxin is produced by Fusobacterium necrophorum?

Answer 5

Leukotoxin - toxic to leukocytes, macrophages, epithelial cells

Question 6

Which toxin is produced by Trueperella pyogenes?

Answer 6

Pyolysin - cholesterol dependant cytolysin

Question 7

Which virus is associated with metritis?

Answer 7

Bovine herpes virus 4

Question 8

What is clinical endometritis?

Answer 8

Inflammation of the endometrium (inside layer of the uterus) usually caused by bacterial infection

Question 9

How is clinical endometritis diagnosed?

Answer 9

Purulent uterine discharge seen on clinical exam

Can scan the cow or investigate the uterus to confirm the discharge present

Question 10

Which pathogens are involved in clinical endometritis?

Answer 10

• Trueperella pyogenes
• Fusobacterium necrophorum
• E.coli?

Question 11

What is subclinical endometritis?

Answer 11

Inflammation of the endometrium; usually caused by bacterial infection.

Question 12

How is subclinical endometritis diagnosed?

Answer 12

• Associated with poor reproductive performance
• Usually based on clinical signs – but not an obvious purulent discharge
• Cytology

Question 13

What is cervicitis and vaginitis?

Answer 13

Inflammation of the cervix, vagina

Question 14

What is the main viral cause of vaginitis and how does it spread?

Answer 14

Infectious bovine Rhinotracheitis virus
(bovine herpes virus)
Spread through infected bulls

Question 15

Describe the features of Campylobacteriosis

Answer 15

• Affects cows reproductive tract/ bulls prepuce
• Causes chronic endometritis
• Early embryonic death and abortions
• STI

Question 16

Why is Camplyobacteriosis not very common?

Answer 16

Spread during natural mating and now AI is most commonly used

Question 17

What is pyometra?

Answer 17

Intrauterine accumulation of pus (usually large amounts)

Question 18

How is abortion defined?

Answer 18

Any fetus dead or alive born 270 days or earlier after conception

Question 19

What are some examples of pathogens that cause abortion in cattle?

Answer 19

• Infectious bovine rhinotracheitis (BHV 1 - IBR)
• Bovine viral diarrhoea
• Leptospirosis
• Neospora
• Campylobacter
• Salmonella

Question 20

What are the two distinct biotypes of bovine viral diarrhoea?

Answer 20

Non-cytopathic

Cytopathic

Question 21

What are the effects of non-cytopathic BVD at different points in pregnancy?

Answer 21

1st trimester infection (0-95days) = foetal reabsorption/abortion
Day 95-120 = Immunotolerance
Day 120-285 = Seropositive foetus, congenital lesions

Question 22

What is the importance of calves that are immunotolerant to BVD?

Answer 22

• They shed the virus their whole lives = persistently infected
• They don’t have antibodies against the virus but they do have antigens

Question 23

Cytopathic BVD is associated with?

Answer 23

Mucosal disease in persistently infected animals

Question 24

How is leptospirosis in cattle spread?

Answer 24

by contact with skin, mucous membranes or orally

Question 25

What are the clinical signs of a cow infected with Leptospirosis?

Answer 25

• Persistent infection of reproductive tract (bull and cow) can result in infertility and shedding in discharges
• Abortions, stillbirths and weak calves in acute infection
• Retained foetal membranes

Question 26

How is Leptospirosis diagnosed in cattle?

Answer 26

• Bulk milk antibody testing gauges level of infection in herd
• Serology by MAT
• Identification of leptospires from aborted tissue, blood or urine by IF or PCR