Ruminant Abortions

What are the three major parasitic causes of ruminant abortions?

• Neospora caninum

• Toxoplasma gondii

• Tritrichomonas foetus

How is Neospora caninum transmitted between cows?

Transplacental

True or False: N. Caninum is extraintestinal in cattle.

TRUE

What is the infective stage of N. Caninum in cattle?

inghestion of sporulated oocysts

What is the easiest way to diagnose n. Caninum in necropsy?

Brain and heart necrosis

What are the three patterns of n. Caninum in cattle?

• Abortion storm (epidemic)

  • Feed/water contaminated

• Low steady abortion losses (endemic)

  • Congenitally affected cattle

• Subclinical infections

What is the preferred sample to diagnose n. Caninum?

aborted fetus with placental for histopathology

True or False: N. Caninum is zoonotic.

FALSE

What is the intermediate host of t. Gondii?

Cats

How does T. Gondii cause abortions in cattle?

tachyzoites reach placenta and cause abortions

What is the major cause of abortion in sheep and goats?

T. Gondii

When is abortion in sheep/goats most common?

3rd trimester

How do you diagnose T. Gondii?

• IgM - active/recent infection

• IgG - must be paired AB 2-4 weeks apart and need a 4x increase for infection

What has been given to control T. Gondii to late gestation ewes?

Ionophores

Is T. Gondii zoonotic?

YES

Where is bovine Tritrichomonas in the animal?

Males: preputial and penile mucosa

Females: Urogenital tract

How is t. Foetus transmitted in cattle?

Veneral

What stage of pregnancy is usually seen abortions in infections with t. Foetus?

early embryonic death

True or False: Infected female cattle with T. Foetus are partially immune and can usually carry the next fetus to term.

TRUE

What is the most common C/S of T. Foetus in cattle

return to estrus after being determined pregnant or irregular estrus cycle

True or False: Older bulls are more resistant to T. Foetus infections.

FALSE - younger bulls

How can you diagnose T. Foetus in cattle?

• Culture trophozoites in TYM Diamonds media (InPouch)

• PCR

In bulls, Y foetus detection requires ____ sample for 80-90% of positives and _____ weekly samples for >99%.

1, 3 consecutive

True or False: All bulls must be negative based on a real-time PCR according to AL law.

TRUE

What age do all bulls entering AL need to be tested for T. Foetus 60 days prior to entry?

18 months and older

WHat is the exemption to T. Foetus testing of bulls?

Exhibitiona nd rodeo bulls, slaughtered directly, virgin bulls <18 months

What drug CANNOT be used in cattle?

metronidazole