PRACTICAL: pregnancy and abortion

Question 1

2 viral causes of abortion in horses

Answer 1

EHV1 and EAV

Question 2

Where does EHV persist?

Answer 2

CNS and lymphoreticular cells –> latent infection. When reactivated, shed via respiratory tract

Question 3

Where does EAV persist?

Answer 3

accessory glands and shed via semen

Question 4

Name 2 viruses that may cause pig abortion

Answer 4

PRRS

Swine flu

Question 5

How do you test for PRRS?

Answer 5

Foetal tissue sample (spleen = best) –> PCR
ELISA (paired serum sample, sow)) - only shows exposure

[Virus isolation - less efficient, more expensive
Foetal serum on free foetal fluids - not as diagnostic]

Question 6

How do you test for swine flu?

Answer 6

deep nasal swab (if showing acute signs) + RT-PCR
OR
Paired serum samples of sows, HIT

Question 7

What should be your main differential diagnosis for feline abortion? Diagnostic test for this?

Answer 7

FeLV
Immunofluorescenc (or PCR) on tissues from aborted foetuses
Snap/Ag test on adult cat serum sample

Question 8

Main cause of canine abortion?

Answer 8

CHV-1

Question 9

How to prevent CHV-1-induced abortion?

Answer 9

Keep animals warm (virus replicates faster in colder environments)
Vaccinated bitch

Question 10

What may cause bovine infectious vulvovaginitis?

Answer 10

BHV-1 (also causes IBR)

Question 11

Name 4 viral causes of abortion in cattle

Answer 11

BVDV
BHV-1
Schmallenberg
BTV

Question 12

What is the most frequent most of transmission for BVDV?

Answer 12

Faecal-oral>respiratory. Also vertical

Question 13

What is the most frequent most of transmission for BHV-1?

Answer 13

Respiratory

Question 14

What is the most frequent most of transmission for SBV and BTV?

Answer 14

Arboviruses - Culicoides

Question 15

What clinical signs do sows show if they have cystic follicles?

Answer 15

Anoestrous (nymphomania usually cows/horses)

Question 16

What is the pathogenesis of endometrial hyperplasia?

Answer 16

Endometrium has entered a secretory phase following prolonged exposure to P4 after E2 priming. Secretory endometrium appears nodular and thickened in this advanced case, cystic changes may also be present.

Question 17

Clinical signs - canine pyometra

Answer 17

PU/PD, decreased appetite/anorexia, vomiting, +/- vaginal discharge
WHEN? 3-6 weeks after oestrous (metoestrous/P4 phase)

Question 18

Which ovary do chickens have?

Answer 18

Left (Right remains vestigial sometimes)

Question 19

What does epipididymitis look like?

Answer 19

Enlarged epididymis,

firm and nodular due to large amounts of fibrous tissue, inflammatory cells and spermatic granuloma

Question 20

Causes of epididymitis in rams - 3

Answer 20

Brucella ovia
Actinobacillus seminis
Histophilus somni

Question 21

Describe mummification

Answer 21

foetal death followed by foetal tissue and fluid reasbsorption. No secondary bacterial infection. Possible cause in pigs is porcine parvovirus

Question 22

Signs of toxoplasma

Answer 22

‘Strawberry pip lesions’ on placenta

White foci of necrosis and mineralisation in bright red cotyledons

Question 23

Appearance of an EAE placenta

Answer 23

much thickened in the intercotyledonary area, covered by some exudate

Question 24

Diagnosis - EAE

Answer 24

impression smear of placental intercotyledonary tissue stained with mZN (Koster stain) which illustrates presence of pathogens

Question 25

Diagnosis - Toxoplasma gondii

Answer 25

Foetal serology on free foetal fluids (pleural, pericardial, peritoneal)

Question 26

How would you identify Salmonella infection?

Answer 26

Stomach culture --> gram stain --> pink MacConkey: gram - grow, yellow = NLF (e.g. Salmonella) O2 and AnO2 media: grows in both Selenite broth: selects for Salmonella (E.coli grows too but less well). XLD media with phenol red - xylose fermentation --> yellow media colour change (e.g. Salmonella). Colonies that can convert thiosulphate to hydrogen sulphate turn black (e.g. Salmonella, n.b. Proetus spp can also do this)

Question 27

How can you confirm Salmonella infection?

Answer 27

``` Biochemical tests (API 20E) Serological identification of Salmonella antigens (O and H) ```

Question 28

How can you culture Chlamydophila abortus?

Answer 28

Not possible in artificial medium No routine culture Tissue culture only