Small Ruminant Abortion

Causes of abortion in sheep/goats

• Campylobacteriosis- bacteria

• Q-fever- bacterial

• Toxoplasmosis- protozoa

• Salmonellosis- bacteria

• Chlamydiosis- bacteria

*All zoonotic

What to do when ewes start aborting?

• Involve veterinarian

• Use appropriate hygienic measures (stop working with ewes if pregnant)

• Pre-emptive treatment

• Eliminate sources of potential infection

  • Dispose of fetuses and fetal membranes

  • Isolate aborting ewes- 3 weeks

  • Isolate ewes that have weak/dead lambs

  • Treat bedding from sites of abortion as contaminated- burn or compost

Most common cause of abortion in WY sheep

Campylobacter

Control of campylobacter during outbreak

• Antibiotics (early on)

• Minimize transmission/exposre

Control of campylobacter in subsequent years

• Vaccination

• Graze replacement ewes with infected older ewes

• Endemic problem in some flocks despite control measures

Time period of salmonella abortion

Late term abortion in sheep

Q-fever in sheep and goats

• Goats»sheep

• Common in WY

• Highly infectious

• Zoonotic

Q-fever in humans

• Route of infection- inhalation of particles from the placenta and fetal fluids

• 10 micro-organisms are sufficient to cause infection

• Human disease- abortion, pneumonia, heart disease

Toxoplasma abortion in sheep/goats/pugs

• Most common cause of ovine abortion in some countries/areas

• Caused by protozoan parasite Toxoplasma gondii

• Infection via ingestion

• Antibiotics will not help during outbreak

• No direct transmission

• Rare in WY

• Zoonosis- abortion sever disease in immune suppressed

• Definitive host- cats

• Intermediate hosts- chicken, rats, small ruminants

• If previous exposure, ewe is immune (no abortion)

Toxoplasma abortion in sheep/goats gestation stage effects on pregnancy

• Early pregnancy- foetal loss/ resoprtion

• Middle pregnancy- abortion, born weak, mummified (dried out)

• Late pregnancy- congenitally infected lamb

Congenitally affected lambs

• May appear normal, but persistently infected

• Do not abort from toxoplasma as adults

Toxoplasma persistence in environment

Oocysts persist in soil but survival depends on moisture content

Toxoplasma control

• Dispose of infectious material

• Food/water security

• Keep previously aborted ewes

• Rodent control

• Spay/neuter cats

• Clean/disinfect

• Vaccine

Chlamydia abortion in sheep/goats

• Zoonotic

• High abortion rate when newly introduced, then reduced abortion rate after 2-3 years

• Can cause high rates of infertility

Chlamydia abortion

• Infection only occurs at lambing time

• Infected during early-mid pregnancy causes abortion and aborted material is highly infectious

• Infected during late pregnancy does not cause abortion, but ewe will become carrier and may abort the next year

• Ewes that abort will not abort again but will continue to be low-level carriers- lambs will be infected via secretions

• Introduction of disease one year will usually cause abortions the next year.

Prevention and control of chlamydophila

• Minimize transmission

• Closed flock

• Biosecurity

• Vaccine

• Retain ewes that abort to boost immunity, cull if goal is to eradicate