Neospora Flashcards
What does Neospora caninum affect?
Dogs - neonatal paresis (muscle weakness)
Cattle - abortion
What are the intermediate + definitive hosts?
Intermediate = dogs + cattle
Definitive = dogs
What is the dog - cow - foetus life cycle
- Dogs scavenge infected bovine tissues (bradyzoites)
- Enteric sexual cycle, syngamy with macro and microgametes to form a zygote, excreted as an oocyst
- Oocysts excreted in dog faeces, contaminate food and water, ingested by pregnant cattle
- Tachyzoites cross the placenta and infect the foetus
* Abortion
* Persistently infected calf
Are all calves born of infected cows going to be infected calves?
Almost always yes. 95% of born calves
high chance of abortion
How many annual abortions is neospora responsible for?
- 35% of diagnosed bovine abortions in UK
- 6000 abortions per annum
How would you diagnose a neospora associated Abortion?
Maternal serology – ELISA
* antibody levels fluctuate during reproductive cycle
* testing cows during second half of pregnancy
* eliminate other causes – BVD, IBR or leptospirosis
Foetus
* antibody detection in foetal fluids
* histology
* brain / heart
* non-suppurative encephalitis
* immunohistology
* PCR
How do you control neospora? (endogenous transmission - cattle)
- Identify positive cows
* Serology of whole herd
* Test calves at birth, indication of dam status but beware of pooled colostrum - Cull infected cows - expensive and depends on number infected
- Selective breeding to beef
* No cow to cow transmission
* No zoonotic risk - Embryo transfer – ensure recipients are negative
How do you control neospora? (exogenous transmission - dogs)
- Reduce the risk of infection of dogs
* Dispose of afterbirth or aborted material carefully - Minimise risk of contamination of cattle feed with dog faeces
- Biosecurity
- Role of pet dogs
- Role of foxes
