Bovine Infectious Infertility and Abortion

Question 1

Define early embryonic death

Answer 1

Fetal death <42 days/8weeks

Question 2

Define abortion

Answer 2

occurs b/t 42 or 56 days & 260 days of gestation

Question 3

Define stillbirth

Answer 3

fetal death >260 days

Question 4

Why is it important to keep in mind the intervention level is <5% ?

Answer 4

In order for us to say, hey listen - your farm is having a problem, you’re seeing more abortions, and I think we should chase down WHY we’re seeing this, let’s send in some tissues and see what’s going on…

That’s what she said in class🤷🏻‍♀️

Question 5

For the most part, in general…

The only time you’re going to see a sick cow & THEN an abortion is when the infectious pathogen is…..?

Answer 5

Listeria monocytogenes

history will be:

• new silage
• hay bales + rain

concentrated in rotting hay & improperly stored silage

Question 6

How do cows become infected with Listeria and how does it cause abortion?

Answer 6

Pathogenesis

ingestion→ replication in monocyte-MF→ placenta
→ placentitis & fetal septicemia→ abortion

*has a predilection for fetoplacental tissues*
**causes abortion inlast trimester**

Question 7

What infectious disease are we thinking?

Answer 7

Listeria monocytogenes

• fetus is often autolysed
  {similar to BHV-1: foci of necrosis in liver}
• Pinpoint yellow, necrotic foci on tips of cotyledonary villi w/focal or diffuse intercotyledonary placentitis

Question 8

T or F:

All Leptospirosis serovars are zoonotic.

Answer 8

• *TRUE.**
• they’re aerobic spirochetes…*

Question 9

What’s the issue with “host-adapted” Lepto?

Answer 9

sets up shop & create an infertility
→ figuring out why the cow is not getting pregnant is going to be a problem
— Lepto has to be on that differential list —
but there will be other things on it too…

Question 10

What’s the main Lepto serovar associated with the host-adapted insidious reproduction loss and/or infertility?

Answer 10

Leptospira interrogans hardjo-prajitno

*important esp.when considering vaccine*

Question 11

Incubation period for Lepto?

Answer 11

4-10 days

Question 12

What would strongly indicate a non-host-adapted Lepto infection?

Answer 12

Abortions
{pomona, grippo, ictero, canicola, etc.}

Question 13

How is Lepto diagnosed?

Answer 13

induce urination via furosemide injection
…x2

because we want to flush it out from the renal tubules

antibody titers not helpful

Question 14

Characteristic lesion for Brucella abortus…?

Answer 14

{G— coccobacillus - intracellular}

Moroccan leather

caused by chorioallantois necrosis

Question 15

What does a human experience when infected with Brucella abortus?

Answer 15

undulant fever

Question 16

What bacterial agents would we be thinking about in small ruminants?

Answer 16

Chlamydia
Salmonella

Question 17

Campylobacter foetus veneralis
aka vibrio

typically causes what?

Answer 17

• Late return to estrus

{go thru a cycle, then come back into heat, but at an abnormal period of time}

• early embryonic death

*the bull is the carrier, but is not really affected - just spreading it*

Question 18

How do we diagnose Campylobacter foetus veneralis ?

Answer 18

We take a long rod, attach it to the end of a large syringe,
pass it into preputial area (or vaginal mucus) & move it back & forth…
goal is to scrape some mucosa —> send off on Clark’s Media

Question 19

How do we diagnose Tritrichomonas foetus?

Answer 19

Preputial scrape vs. wash
{lab preference}

samples go onto Diamond’s media or inPouch
→ cultured & sent to lab for observation of Protozoa

Question 20

When should Tritrichomonas foetus testing be done?

Answer 20

After 2 weeks sexual rest

*once a week, 3 weeks in a row…

NEEDS to be 3 weeks to be able to say Tritrich-free*