FASH7-8: Ovine Abortion and Poor Reproductive Performance Flashcards
What is the cause of high barren rates in sheep?
Ewes not cycling
Fertilisation failure
Failure to conceive or maintain early pregnancy
What are some causes of ram infertility?
- Epididymitis
- Inguinal hernia
- Testicular degeneration
- Scrotal mange
What are the agents that cause epididymitis?
Actinobacillus semnis
Haemophilus somnus
Histophilus ovis
How do organisms enter the repro tract of the ram?
Organisms enter the repro tract through the prepuce from the environment
What does testicular degeneration look like?
Bilateral small testes with poor semen quality
What factors lead to testicular degeneration?
Systemic disease
ENvironmental temp
Inflammation
Extremem fatness
What is the agent that causes scrotal mange?
Chorioptes bovis
When you handle the scrotum of a ram with scrotal mange, what do they do?
Nibbling reflex
What are the agents that cause abortion?
- Chlamydophila abortus
- Toxoplasma gondii
- Salmonella
- Campylobacter fetus fetus
- Border disease
- Listeriosis
What is the agent involved in enzootic abortion fo the ewe?
Chlamydophila abortus
ZOONOTIC
What are the characteristic signs of enzootic abortion of the ewe?
Late abortion (last 2-3 weeks gestation), stillborn or weak lambs
Intercotyledonary placentitis
How do you diagnose EAE?
Placentitis
Smears
ZN stain
How does EAE spread?
infection by ingestion or inhalation from a contaminated environment
- Placenta
- Vaginal discharge
- eLabs coats
- Fomites
How does pregnancy period impact abortion status when infected with EAE?
- Infection during late pregnancy/non-pregnant > abortion next pregnancy
- Infection during first half of pregnancy > abort during last three weeks of pregnancy
- Surviving ewe lambs from aborted ewes > abort during first pregnancy
- Once aborted > ewes become immune but may continue to shed organism
How do you manage an EAE outbreak?
Isolate aborting ewes immediately and included any living lambs in order to reduce onward infection of ewes
Remove contaminated bedding
Treat all ewes with oxytetracycline
How to you prevent EAE?
Isolate aborting ewe immediately
Vaccinate all unexposed ewes and ewe replacements
Maintain a closed flock
Source replacements from accredited-free farms
What is the agent behind toxoplasmosis?
Toxoplamsa gondii
When does infeciton impact abortion?
Barren ewes if infection is in early pregnancy
Abortions/stillbirths if infection is in late pregnancy
Normal if infected after 120 days or when empty
What should you do with suspected toxoplasmotic placenta and lambs?
Submit it to the VI center
Include: foetal brain, foetal fluid serology, maternal serology
How do you manage a toxoplasmosis outbreak?
Not a whole lot can be done…
Decoquinate in feed
Avoid spreading bedding material on pasture
How do you prevent toxoplasmosis?
Protect food from cats
Vaccinate
What is the agent in campylobacteriosis?
C. fetus fetus - gram neg
When are lambs aborted due to campylobacteriosis?
final 6 weeks of pregnancy
How is campylobacteriosis spread?
There are carrier ewes that contaminate environment from aborted material and vaginal discharges
Carrion-eating birds
Trough feeding
NO VENEREAL SPREAD
How do you diagnose campylobacteriosis?
Gram or ZN stain of foetal stomach contents
Bacterial culture of foetal stomach contents
How do you control a campylobacteriosis outbreak?
Isolate aborted ewes
Reduce the level of environmental contamination
What is the agent of salmonellosis?
Salmonella enterica
What is characterisits of salmonellosis?
Often rotten ,atuolysed lambs
How do you diagnose salmonellosis?
MacConkey agar from placenta, foetal stomach contents, vaginal swabs from ewe where no abortion products available
How do treat and manage salmonellosis?
Whole flock antibiotic therapy
Isolate aborted ewes
Hygienic precautions (zoonotic)
Environmental hygiene
What is border disease related to?
BVD in cattle
How does infection during pregnancy affect the outcome of the lamb?
<day>
<p>Day 60-85: some normal lambs, some with CNS abnormalities</p>
<p>Day 85: late abortions or normal survivors</p>
</day>
How do you control against border disease?
Closed flock
Cull affected lambs/ewes
Don’t retain homebred ewe lambs if farm affected
