17.4.3: Farm animal abortion Flashcards
Which is more common in cattle:
a) abortion due to an infectious cause
b) abortion due to a non-infectious cause
b) abortion due to a non-infectious cause
Which is more common in sheep:
a) abortion due to an infectious cause
b) abortion due to a non-infectious cause
a) abortion due to an infectious cause
True/false: abortion is the main cause of reproductive failure in cattle.
False
Early embryonic death is the main cause of reproductive failure in cattle.
What are some possible non-infectious causes of abortion?
- Hereditary disorders/congenital defects
- Teratogens e.g. plants (lupins)
- Poisons e.g. ergot, nitrates, brassicae, mycotoxins, hemlock
- Trauma/physical factors
- Prostaglandins: endogenous (stress/inflammation/pyrexia) or exogenous
- Nutritional deficiencies e.g. severe starvation, Vitamin A, Iodine, Selenium
- God only knows
Any systemic infection can make a cow lose her calf if it leads to sufficient ________________ release to cause regression of the corpus luteum.
Any systemic infection can make a cow lose her calf if it leads to sufficient prostaglandin release to cause regression of the corpus luteum.
In these cases it is important to take a good history of the dam’s health as there may be nothing wrong with the foetus.
Of the following bacterial causes of abortion in cattle, which ones are zoonotic and notifiable?
1. Leptospira hardjo
2. Salmonella spp.
3. Bacillus licheniformis
4. Listeria monocytogenes
5. Brucella abortus
6. Trueperella (Arcanobacter) pyogenes
All are zoonotic and notifiable.
Of the following viral causes of abortion in cattle, which ones are notifiable?
1. BVD
2. IBR
Neither
What is a possible protozoal cause of abortion in cattle and is it notifiable?
Neospora caninum
Not notifiable
What is a possible fungal cause of abortion in cattle and is it notifiable?
Aspergillus
Not notifiable
True/false: typically a foetus is expelled immediately after the dam has come into contact with a toxin.
False
It may take weeks-months for the foetus to be expelled so the cause of the abortion may be a historical issue.
Which is easier to diagnose:
a) infectious causes of abortion
b) non-infectious causes of abortion
a) infectious causes of abortion
What is the causative agent of EAE?
EAE: enzootic abortion of ewes
Causative agent: Chlamydia abortus
Describe the characteristics of Chlamydia abortus, and when abortion generally occurs with this pathogen
- Chalmydia abortus: gram-negative, intracellular bacterium
- Abortion is generally in the last 3 weeks of gestation
How is EAE transmitted and how does it infect ewes?
- Infection is oral
- Animals affected before or during pregnancy may abort
- Organism is spread in aborted material and venereal fluids
- Some ewes become carriers and may excrete organism in their faeces (this is uncommon)
True/false: if animals are infected with Chlamydia abortus before pregnancy, they will not abort.
False
Animals infected before or during pregnancy may abort