FOP 2 Equine notes + presentation Flashcards
overall pregnancy rate in mares
50%
in mares, when investigating failure of pregnancy, is it more important to investigate the placenta or the fetus?
arguably, the placenta
why is the birth of live twins so rare in horses?
lack of functional reserve in the equine placenta
when will we see a lack of villi in regions of the equine placenta?
- Twinning, where the connecting surfaces of adjoining
placentas meet. - Ascending infection, which is one of the common ways
that agents gain access to the fetus and membranes in
horses. - Premature separation of the placenta, that occurs, in
part, with cervical laxity or with body pregnancies.
>body pregnancy is where umbilical cord and fetus attach in body of placenta rather than horn: pushes out cervix, so we get avillus area where placenta sticks out of the ervix
length of the normal umbilical cord in the mare. What happens if it is too long, or too short?
-normal is between 36 and 83 cm long
-Longer may strangle the fetus, develop torsion, and necrosis of the cervical pole of the placenta.
- shorter may rupture prematurely in labour or prematurely separate at the site of attachment.
how many twists should the equine umbilical cord have?
The cord should have no more than 4 twists.
how often can we determine the cause of failure of pregnancy in the mare by examining the placenta and umbilical cord?
1/2 of cases
what region of the placenta is it important to examine to determine the cause of FOP in the mare? why?
cervical star
-most infectious cases (aside from EHV) are related to ascending vaginal infection
Infection and inflammation of the placenta releases what?
-proinflammatory cytokines that cause fetal ‘distress’ and abortion
what fetal changes can Equid alphaherpesvirus 1 cause?
An important cause of abortion and there are prominent changes in the fetus. One or more of the following may be found
* fibrin cast in the trachea
* interstitial pneumonia
* focal necrosis in the liver
common way to begin an outbreak of EHV-1 in a group of mares:
Introduction of an infected mare to a group of naïve mares
what type of vaccine do we have for Equid alphaherpesvirus 1?
killed vaccine that requires multiple injections
normal fetus to placenta weight ratio is what? why should we weight these?
normal ratio is 10:1
-can examine to identify placental edema – an indication of fescue toxicosis
What part of the chorioallantois would you routinely sample when investigating an abortion?
cervical star - this is where infectious disease occurs most often in equine placentas
Mummification of a fetus in mares is associated with what situations?
twins