Bovine Abortions Flashcards
What cows should you assess first in abortion storm work-ups?
Those who have aborted most recently
What should you always submit to the lab when working up abortion cases when available? What should you always collect from moms?
Fetus and placenta
Blood
What does campylobacteriosis usually result in?
Infertility
What strains of campylobacter are more likely to cause sporadic late term abortions in cattle and small ruminants?
Campylobacter fetus ssp fetus and C jejuni
How is campylobacter spread from cow to cow?
Feco-oral
When does the majority of pregnancy loss occur with campylobacteriosis infections?
30-70 days gestation
What is the pathogenesis of how campylobacteriosis leads to abortion?
A heat stable endotoxin is produced with leads to placentitis. Swelling of placenta then leads to fetal hypoxia
How long does it take for infected cows to develop immunity against campylobacteriosis?
4-8 months
How do you diagnose campylobacteriosis?
rtPCR or IHC
What can mollicute (mycoplasma/ureaplasa) cause in pregnant animals?
Embryonic death, abortion, stillbirth, weak calves, neonatal pneumonia- AKA abortion can occur anytime!
How do you diagnose mollicute infections?
PCR of vaginal/preputial swabs, abortion-culture/PCR from fetal tissues
What type of antimicrobial is most effective against mollicutes?
Macrolides
What type of virus is BVD?
RNA, pestivirus, flaviviridae
Where is the site of inoculation of BVD infections?
Tonsils and Respiratory tract- then disseminates to other epithelial/lymphoid tissue. Can result in transplacental infections
What occurs when cows are affected at breeding with BVD?
Decreased conception rate due to embryonic loss
-etiology: oophoritis, salpingitis, hormone alteration
During what time frame during pregnancy can infection with BVD lead to persistent infection in fetus?
40-125 days!
What occurs if cows are affected between 100-150 days in pregnancy with BVD?
Congenital malformations-organogenesis, cerebellar hypoplasia, hydrancephaly, hydrocephalus, porencephaly, ocular changes
What occurs if infection with BVD occurs >125 days into pregnancy?
Abortions rarely, usually clinically normal calf with high levels of precolostral antibodies
How can you control BVD infections?
ID and remove PI animals, enhance immunity through vaccination (MLV before pregnancy ideal), biosecurity to prevent exposure
What type of virus is bluetongue and how is it transmitted?
orbivirus transmitted by culicoides varripennis