Exam 2: Bovine Infectious Infertility and Abortion

Question 1

Early embryonic death is defined as fetal death occurring

before _______ weeks gestation

Answer 1

8 weeks

Question 2

Still birth is defined as fetal death occurring at

greater than _________ days

Answer 2

260 days

Question 3

Intervention level for infectious infertility and abortions is

> ____% of the herd

Answer 3

>5%

Question 4

The #1 diagnosis of abortion is _________

Answer 4

UNKNOWN!

Question 5

In cases of abortion, what tissues at a minimum should be

submitted for diagnostics?

Answer 5

Placenta, Fetus, Maternal Blood

Question 6

Describe the shape of Listeria monocytogenes

Answer 6

Gram positive coccobacillus

Question 7

This bacterial cause of abortion in cows is concentrated in

rotting hay and improperly stored silage

Answer 7

Listeria monocytogenes

Question 8

Listeria monocytogenes causes abortion in

which trimester?

Answer 8

Listeria monocytogenes causes abortion in the

last trimester

Question 9

This is one of the few causes of abortion in cattle that you

actually see sick, infected cows before, during, and after abortion,

along with encephalitis and neonatal disease

Answer 9

Listeria monocytogenes

Question 10

Upon necropsy of an aborted fetus,

you notice the fetus is autolysed.

The liver shows foci of necrosis, but you have ruled out BHV-1.

What is your primary ddx?

Answer 10

Listeria monocytogenes

Question 11

The placenta described below most relates to which bacterial cause of abortion?

Pinpoint yellow necrotic foci

on the tips of cotyledonary villi

with intercotyledonary placentitis

Answer 11

Listeria monocytogenes

Question 12

What is the treatment for Listeria monocytogenes?

Answer 12

No treatment, cow recovers.

Prevention aimed at proper feed and silage storage

Question 13

All serovars of this aerobic spirochete bacteria are zoonotic

Answer 13

Leptospirosis

Question 14

Host-adapted Leptospirosis that result in

insidious repro loss and infertility include

these 2 strains

Answer 14

• L. interrogans hardjo-prajitno* (USA)
• L. borgpetersenii hardjo-bovis* (UK)

Question 15

Name the 4 types of Leptospirosis that are non-host adapted

and responsible for abortion storms

Answer 15

• L. pomona*
• L. grippotyphosa*
• L. icterohemmorhagica*
• L. canicola*

Question 16

Leptospirosis has an incubation period of _________ days

Answer 16

4 - 10 days

Question 17

Leptospirosis localizes and persists in the _________

Answer 17

renal tubules

Question 18

T/F:

Leptospirosis infection has pathognomic clinical signs

that all animals show if infected

Answer 18

FALSE!

Often NO clinical signs with lepto infection

Question 19

How is Leptospirosis transmitted?

Answer 19

Urine

Placental fluids

Milk

Transplacental

Semen

Question 20

Leptospirosis can survive in a wet enviroment for ______ days

Answer 20

30 days

Question 21

How is Leptospirosis diagnosed?

Answer 21

Via clinical history of INFERTILITY and ABORTIONS

plus fluorescent antibody test

of maternal urine after FUROSEMIDE administration

Question 22

What type of vaccine protects from non-host adapted Leptospirosis?

Answer 22

multivalent vax

Question 23

What type of vaccine protects from host adapted Leptospirosis?

Answer 23

monovalent vax

Question 24

During an outbreak, how is Leptospirosis controlled?

Answer 24

Vaccine + TETRACYCLINES

Question 25

This **gram negative intracellular coccobacillus** was once the most important repro disease of cattle in the USA. Thank to an **eradication** program, most states are free, but we must remain vigilant because the associated zoonosis results in **undulant fever**

Answer 25

*Brucella abortus*

Question 26

How is Brucella abortus transmitted?

Answer 26

Primarily via mucous membranes

Question 27

Where does Brucella abortus multiply?

Answer 27

**chorioallantoic trophoblasts** resulting in chorioallantoic necrosis and fetal bacteremia

Question 28

T/F: Bulls can be carriers for Brucella abortus and transmit it via coitus with the cow, which is why all sire bulls should test negative for it

Answer 28

True (But transmission via coitus is rare)

Question 29

When do abortions typically occur if a cow is infected with *Brucella abortus*?

Answer 29

After 5 months gestation

Question 30

Following abortion around 5 months due to *Brucella abortus*, what sequela can you see in the cow?

Answer 30

Retained fetal membranes, Metritis

Question 31

What tissues can be submitted to confirm diagnosis of Brucella abortus?

Answer 31

FETAL lung, abomasum Placenta Uterine tissues

Question 32

What might the placenta of a cow infected with Brucella abortus look like?

Answer 32

dry, thickened, or cracked intercotyledonary areas, moroccan leather

Question 33

How do you treat cows that test positive for Brucella abortus?

Answer 33

NO treatment, **CULL**

Question 34

You go to a farm and the farmer tells you his cows have been aborting around 5 months gestation. Afterwards, some cows experienced retained fetal membranes and metritis. What is your primary differential, and what is the first thing you do?

Answer 34

Brucella abortus ## Footnote **report it to authorities!**

Question 35

How is Brucella abortus prevented?

Answer 35

Vaccination of **HEIFERS ONLY**

Question 36

What is the name of the vaccine used in heifers (not males!) to prevent ***Brucella abortus***?

Answer 36

RB51 (Bang's Vaccine)

Question 37

When are heifers vaccinated for ***Brucella abortus***?

Answer 37

vax at 4 -12 months, NEVER OVER 1 YEAR!

Question 38

What is the best source of new animals to ensure you do not introduce an animal infected with Brucella abortus?

Answer 38

Certified Brucellosis Free Herds

Question 39

These 2 bacteria are found in the normal female reproductive tract but some strains can cause granular vulvovaginitis and salpingitis that can lead to infertility. They are an uncommon cause of early and late term abortions in cows

Answer 39

Mycoplasma, Ureaplasma

Question 40

**Vibrio** is another name for this bacterial cause of abortion in cattle

Answer 40

*Campylobacter foetis veneralis*

Question 41

This gram negative microaerophilic rod/comma shaped bacteria causes **early embryonic death** and is transmitted via coitus

Answer 41

*Campylobacter foetis veneralis*

Question 42

What is the most common clinical sign of Campylobacter foetis veneralis seen in cows?

Answer 42

Delayed return to estrus

Question 43

While most cow infected by ***Campylobacter foetis veneralis*** experience early embryonic death, less than 10% abort a fetus at ______ months

Answer 43

4 - 6 months

Question 44

What is the most common clinical sign of Campylobacter foetis veneralis infection in bulls?

Answer 44

NO CLINICAL SIGNS SEEN IN BULLS!

Question 45

\_\_\_\_\_\_\_\_ media is used to culture bacteria for diagnosis of Campylobacter foetis veneralis

Answer 45

Clark's media

Question 46

What samples should be sent to lab for diagnosis of *Campylobacter foetis veneralis*?

Answer 46

Preputial scrapings Vaginal mucus FETAL abomasum Placenta

Question 47

How is *Campylobacter foetis veneralis* prevented?

Answer 47

Culling the BULLS that are positive. Cows clear it in 3 - 6 months. Vaccinate cows 2 weeks before breeding season: 2 injx, 2- 4 weeks apart Annual booster

Question 48

What are the 3 types of *Campylobacter* that can cause abortion in cattle?

Answer 48

C. foetis veneralis C. fetus fetus C. fetus jejuni

Question 49

* Tritrichomonas foetus* is a: a. bacteria b. virus c. protozoa

Answer 49

protozoa

Question 50

How is *Tritrichomonas foetus* transmitted?

Answer 50

Coitus

Question 51

T/F: *Tritrichomonas foetus* prevents conception

Answer 51

FALSE

Question 52

T/F: *Tritrichomonas foetus* causes fetal loss, usually early embryonic death and bulls are the primary reservoir.

Answer 52

TRUE

Question 53

What are the two differentials for a REVERSE STAIR STEP herd history graph?

Answer 53

*Campylobacter* and *Tritrichomonas*

Question 54

What are some signs seen in herd history for herds with *Tritrichomonas foetus*?

Answer 54

Reverse stair step graph Gradual decrease in herd fertility Prolonged estrus in intervals Early abortions (usually unobserved) Post-coital pyometra **Apparent conception and return to heat in 60 - 90 days**

Question 55

What type of media is used to culture preputial wash for *Tritrichomonas foetus* (protozoa)?

Answer 55

Diamond's media or InPouch

Question 56

What samples should be taken to culture if *Tritrichomonas foetus* is suspected?

Answer 56

Fetal FLUIDS- amnion, abomasum Uterine contents Cervico-vaginal mucus Preputial wash

Question 57

How is *Tritrichomonas foetus* treated?

Answer 57

Use only culture negative bulls less than 4 years old Test and CULL positive bulls Use AI Sexual rest for cows a minimum of 3 cycles Quarantine to divide herd Vaccine- TRICHGUARD (does not prevent dz, shortens recovery!)

Question 58

What vaccine is used to *shorten the recovery time* of ***Tritrichomonas foetus***?

Answer 58

TrichGuard

Question 59

* Neospora caninum* is a: a. bacteria b. virus c. protozoa

Answer 59

c. PROTOZOA

Question 60

What is the definitive host of *Neospora caninum*?

Answer 60

Dogs

Question 61

How is *Neospora caninum* transmitted?

Answer 61

Ingestion of dog/coyote feces Vertical transmission primarily (dam to calf- 80%)

Question 62

Describe the calf of a dam that was infected by *Neospora caninum*

Answer 62

Premature, weak, aborted, *autolysed,* or NORMAL (PI)

Question 63

When do abortions occur in cows infected with *Neospora caninum?*

Answer 63

Usually **3rd trimester,** but can occur at anytime. Cow shows NO CLINICAL SIGNS

Question 64

How is *Neospora caninum* diagnosed?

Answer 64

Immunohistochemistry on fetal tissues and placenta. Serologic testing- once a cow is positive, she stays positive

Question 65

How is *Neospora caninum* prevented and controlled?

Answer 65

Disrupt predator-prey life cycle Dispose carcasses and placentas quickly Store feed and water away from fecal contamination Select negative replacement heifers

Question 66

What is the causative agent of Infectious Bovine Rhinotracheitis (IBR)?

Answer 66

Bovine HERPESVIRUS 1

Question 67

T/F: The venereal form of BHV-1 frequently results in abortion

Answer 67

FALSE! Rare to see abortions. Will see infectious pustular vulvovaginitis and balanoposthitis

Question 68

What is the most frequently diagnosed cause of viral abortion in North America?

Answer 68

INFECTIOUS BOVINE RHINOTRACHEITIS (IBR) ## Footnote *BHV-1*

Question 69

How is IBR/BHV-1 transmitted?

Answer 69

Venereal- Coitus, Instruments, Semen Systemic- From mucous membranes, aborted fetus, respiratory

Question 70

This viral cause of abortion in cattle causes **abortion storms** in which 25 - 60% of cows in a herd abort. Abortions usually occur between **4 and 8 months** gestation

Answer 70

IBR/BHV-1

Question 71

What is important to remember about the IBR/BHV1 vaccine?

Answer 71

The vaccine is a modified-live virus vaccine, and if given in a pregnant animal, can cause abortion!

Question 72

How is IBR/BHV-1 diagnosed?

Answer 72

IHC and microscopic exam shows ## Footnote **intranuclear inclusion bodies**

Question 73

**Bovine viral diarrhea virus** is: a. single stranded enveloped RNA virus b. double stranded enveloped RNA virus c. single stranded enveloped DNA virus d. double stranded enveloped DNA virus

Answer 73

SINGLE stranded enveloped RNA virus

Question 74

What are the different **genotypes** of BVDV (Bovine Viral Diarrhea Virus)?

Answer 74

BVDV 1 and BVDV 2

Question 75

What are the different **biotypes** of BVDV (Bovine Viral Diarrhea Virus)?

Answer 75

Cytopathic and Non-cytopathic (all PI calves!)

Question 76

What is the primary source of BVDV (Bovine Viral Diarrhea Virus) spread?

Answer 76

Vertical transmission via **PI calves**

Question 77

Describe why calves can have different presentations when the cow is infected with BVDV

Answer 77

If cow is infected in early gestation--\> early embryonic death If before 120 days--\> PI calf or abortion If after 120 days--\> congenital effects or normal calf Depends on interaction with placenta

Question 78

What are some congenital defects seen in calves infected with BVDV in utero

Answer 78

Arthrogryposis (malformed joints) Hydrocephalus Microcerebellum Skin deformities

Question 79

What are the sources of horizontal transmission of BVDV?

Answer 79

PI calves = PRIMARY SOURCE Acutely infected animal = sheds 2 days to 2 weeks Shed in tears, feces, saliva, urine, semen, milk Fomites- feeders and waterers

Question 80

How is diagnosis of **PI calves** with BVDV confirmed?

Answer 80

If remains virus neutralization negative on tests 14 days apart If remains virus neutralization positive for 14 days or more

Question 81

What is the gold standard for diagnosis of BVDV?

Answer 81

Virus isolation (but beward of maternal Abs) *buffy coat, serum, tissue*

Question 82

If using immunohistochemistry for diagnosis of BVDV, what is sampled and what confirms a positive?

Answer 82

EAR NOTCH sample with presence of **antiGEN** *maternal antibodies do not interact because looking for antigen*

Question 83

What test is used to screen the entire herd to figure out how prevalent BVDV is?

Answer 83

PCR (beware of false positives)

Question 84

What is the causative agent of Bluetongue Virus?

Answer 84

Orbivirus

Question 85

How is Bluetongue Virus (Orbivirus) transmitted?

Answer 85

*Culicoides*

Question 86

**Bluetongue Virus** (Orbivirus) is a minor cause of abortion. What does it most commonly cause?

Answer 86

TERATOENESIS (cerebral malformations, weak calves, still-borns)

Question 87

What agent is responsible for causing 70% of fungal abortions in cattle?

Answer 87

Aspergillus Fumigatus

Question 88

What lesions do you expect to see on the placenta of an animal infected with Aspergillus Fumigatus?

Answer 88

Necrosis of cotyledons, intercotyledonary thickening

Question 89

What lesions do you expect to see on the **fetus** of an animal infected with Aspergillus Fumigatus?

Answer 89

In 25% of cases: Mycotic plaques that look like ringworm

Question 90

How is *Aspergillus fumigatus* diagnosed?

Answer 90

Fungal hyphae on microscope and histopath