Reproduction: Abortion Flashcards
What is abortion in cows?
Calving that occurs < 270 days gestation
Must be reported
What is the problem of abortion
Repro performance
Reduced milk production
Lower maternal survival
Replacement heifers
What notifiable disease can cause abortion?
Brucellosis
* All abortions reported
* Monthly routine milk sampling
What are infectious and non infectious causes of abortion?
Infectious
* Primary- brucella abortus
* Oppertunistic- damaged barrier- salmonella
Non infectious
* Nutritional
* Developmental hormones
* Toxins- alflatoxins, nitrate/nitrite
* Trauma- insemination, hyperthermia, twinning
What are the target
What 4 vaccines can reduce abortion?
- Lepto
- BHV1
- BVDv
- Brucella
What are the foetal tissues that are responsive to the insult causing abortion?
Chorio-allantois
Amnion
Bone
Soft tissues
Endocrine
Immune cells
Specific cell types
What are primary abortive agents by definition?
- Destroys integrity of foeto-maternal unit
- May/may not cause abortion
- Allows opportunistic pathogens to invade placenta
- Alters microbiolocial profile within pregnant uterus
What are primary infectious abortion causes?
- Brucella abortus
- BVDv
- Lepto
- Neospora
- BHV-1
- Parainfluenxa 3
- Bacillus licheniformis
- Fungi
How do secondary pathogens cause abortion?
- Usually associated with chorionitis/amnionitis
- Associated inflammatory cascade and prostoglandins cause- luteolysis, relaxation of cervix, fetus expelled
What are the most common secondary opportunistic pathogens for abortion?
- Truperella pyogenes
- Listeria monocytogenes
- Leptospira
- Salmonella dublin
- M. tuberculosis
- IBR
- Myoplasma
What are the routes of infection of pathogens for abortion?
- Resident flora of reproductive tract during pregnancy
- Transplacental
- Haematogenous
What are the routes of infection of pathogens for abortion?
- Resident flora of reproductive tract during pregnancy
- Transplacental
- Haematogenous
What agents cause abortions at the following time?
1. Whole 9 months
2. 4-6 months
3. 2-4 months
4. 4-9
- BVD, salmonella, A pyogenes, M tuberculosis
- Neospora
- Trichomonas
- Mycotic, lepto, listeria, IBR, IPV, Bacillus, Brucells, campylobacter
Why can the foetus not ammount an immune response?
T cell recognition of self occurs at around 90-120 days
Why can the foetus not ammount an immune response?
T cell recognition of self occurs at around 90-120 days
- What causes IBR?
- What causes latent carriers?
- How can it be tested and prevented?
- BHV-1
- Trigeminal ganglion
- ELISA, immunofluorescence
Prevention- vaccine
What is the most common diagnosed cause of abortion?
Neospora
Dogs definitive host
4-6 months causes abortion
Or produce PI cow- if after or before
How can pattern of neospora help with diagnosis?
Endemic/grumbling levels
* endogenous transmission
Storm
* Storm
How is neospora diagnosed and controlled?
- Maternal serology- fluctuates
- Naris
- Use increaseing Ab levels as evidecne of recrudesecne
- Test calf at birth
- Dead calf- brain histopath
Control
* Keep dogs away from cattle feed and water
* Culling seropositive
* Breed to beef dont keep replacement
* Use sexed semen
What happens when BVD infects at different periods?
First trimester
* foetal resorption or abortion
95-120d
* Immunotolerance- PI
120-285
* Sero-positive ± congential lesions
* Can abort
Also lowers future pregnancy rate
How is BVD diagnosed?
- Seroconvert over three weeks
- Bulk milk abs
- Detect PI in blood from one month
- Ear notch tissue test
- Check test: abs
- BUlk tank PCR
How is BVD controlled?
- Test the bull
- Test bough in
- Good biosecurity
- Eradicate- testing and removal of PIs
- Sheep: avoid cograzing
- Vaccination protects the pregnancy
What leptospirosis does not cause abortion but infact jaundice and renal failure?
L. icterohaemorrhagiae
What are the clinical signs of leptospirosis (abortion)
How is it diagnosed?
- Often unapparent and cow in latent state
- PI of repro tract
- Abortion, still births, weak calves
- RFM
Diagnosis
Bulk milk ab testing, serology, PCR from aborted tissue
How is lepto treated and controlled?
Tx
* ABs- prolonged oxytet
Risk factors
* Test buying stock
* AI
* Avoid cograzing
* Fence of water
How is campylobacter spread?
Diagnosed
Venereally
Caused mild endometritis
Diagnosis- preputial washing in bulls and vaginal mucus aspiration- campy kit
How is campylobacter spread?
Diagnosed
Venereally
Caused mild endometritis
Diagnosis- preputial washing in bulls and vaginal mucus aspiration- campy kit
What are the clincial signs of trichomas fetus?
Occasionally causes abortion
More commonly poor preg rates, pyo, endometritis
