Ovine Fertility Reprod & Obstetrics Flashcards
What main 4 factors to Poor fertility performance in ewes?
- Nutrition
- seasonality - short day breeders
- Infectious dx
- Stress
What are some infectious causes of poor fertility?
**- Chalmydophilia abortus aka enzootic abortion of ewes (EAE)
- Toxoplasma gondii **
- Campy fetus fetus
- Salmoinella
- Q-fever
- Listeria M
- Border dx
- Schmallenberg
- Bluetongue
Describe the direct & indirect effect of EQE on lambs?
- Inflammation which affects nutrient transition and hormonal contorl of preganncy
- Inflammation of organs of lamb
Describe latent infection of EAE
- Infection of ewe >6 weeks from lambing result sin abortion around 2-3 weeks before lambing
- Infection of ewes closer to lambing can result in latent infection in lining of uterus
= aboriton next breeding season
= abortion storms
What happens to lambs born from infected ewe?
Become carriers
What is the main finding from EAE?
Necrotic placentitis - oedema of intercotyledonary area of placenta
Physiology of Toxoplasma in early pregnancy?
- No immune response from foetus
Early foetal loss, barren, mistaken for infertility
Physiology of ToxoP mid pregnancy?
Foetal loss, or mummification of foetuses (alongside alive lamb) delivered at term
Physiology fo ToxoP late Pregnancy?
Foetus is immune competent, lamb liekly born alove but weak and infected
Describe toxoplasma broadly?
- Second most common cause i UK
- Protozoan parasite
- focal necrosis of cotyledons - strawberry appearance
Describe ‘life cycle’ of toxoplasma transmission?
PATHOPHYSIOLOGY OF BORDER DX?
Describe Campylobacter as Abortion cause?
- 3rd most common cause in UK
- Infected from contaminated water/feed or from material
Infection -> bacteraemia -> placental infection -> abortion, stillbirth, or full term lambs weak
Excretion for 42 d after infection
Carrier sheep
Describe Salmonella infection?
S.dublin, typhi, montevido
- Systemically infected -> high mortality
- Sudden death and rotten lambs
What is Q fever?
Coxiella brunetti
Describe Coxiella b?
- Last week of preganncy
- Goats more affected
- Organism shed in placenta & fluids at parturition
- Diagnosis - detection in foetus : placenta
- Zoonotic
describe Listeria & abortion
- Any stage of pregnancy
- Within 7 days of spoiled feed
- sick, pyrexic ewes
- necrosis of cotyledons and septicaemic foetus
- yellow /white foci on liver of foetus
- Diagnosis - cultured stimach contents
- Associated with RFM & metritis
- Zoonotic
CLS for main causes of abortion ?
What steps to take when abortion happens?
When is an investigation of abortion warranted?
- > 2% of total
- Or 2+ abortion over 2-3 days
How do we diagnose abortion?
- Fresh samples (avoid autolyzed/mummified)
- Minimum lab samples:
maternal serology,
foetus/ foetal fluid from abdo & thorax
foetus stomach contents
Fresh spleen
Placenta > 1 cotyledon
Which samples can be used for what?
Detail Tx & control of abortions
- Prevention: vaccination for EAE & toxo
- Control cat populations
- Feed production & storage (listeria)
- Tx fo individuals with ABs
- Flock level admin of oxytet?
CLOSED FLOCK SYSTEM
Nutritional causes of poor fertility?
-> assess energy balance in sheep with metabolic profiling
- poor nutrition = bad ovulation rate, early embryonic loss, etc
What can we supplement sheep with?
- Copper
- Iodine
- Cobalt
- Selenium
Describe Copper in sheep?
- Molybdenum, iron, and sulphur in soil can result in poor absorption of copper
- Seasonal variation in pastures