Repro 3 Flashcards
define the following: early embryonic death, abortion, stillbirth, non viable neonate
EED: death up to 35-45 days postconception in large animals, 20 days in dogs and cats
abortion: expulsion of the fetus prior to the time of viability
stillbirth: expulsion of a dead fetus at the time of viability
non viable neonate: delivery of a live, weak born animal
is it easy to diagnose something based on fetal loss?
NO! reaching a definitive diagnosis is the excpetion, not the rule
fetal loss is a combo of what 3 factors?
maternal disease, fetal diease, and placental disease
what makes it easier to diagnose a cause for fetal loss?
if there is an outbreak of an infectious agent, if the cause is infectious, if the fetus is fresh, and if the placenta is included
in most species the common known causes of fetal loss are ______, with the exception of?
infectious
horses are unique because they have a lage number of non infectious causes of fetal loss
what are some unique features of horses that cause fetal loss?
twinning, inadequate villus development, premature placental separation, body pregnancy (not enough placenta to go around), umbillical cord anomalies
list some examples of bacterial, viral, and protozoal causes of fetal loss. which ones are NOT zoonotic?
bacteria: brucella, camplyobacter, chlamidyia, leptsospira, listeria, salmonella, NOT ZOONOTIC: mycoplasma, ureaplasma
viruses: herepesviruses and pestiviruses (not zoonotic)
protozoa: toxoplasma gondi, NOT ZOONOTIC: nespora caninium
what will you see in a fetus if it has been infected with a herpesvirus?
multifocal small white foci of necrosis commonly in the liver but can be found everywhere, intranuclear inclusion bodies on histo
what would you see in a fetus that has been infected with a pestivirus like BVD or classical swine fever in pigs?
fetal death or persistent infection or fetal malformation (often CNS), depending on the virus
this is the liver of a fetus. what do you suspect?
infection with a herpesvirus
this is a fetus brain. what could cause this?
infection with a pestivures or parvoviruses (cereballar hypoplasia)
what is the most common oute of infection of the placenta in ruminants and in hoses?
ruminants: hematogenous spread
horses: asceding infection due to loose cervix
once placentitis is esablished, organisms can do what 3 things?
- penetrate the aminion and colonize the skin of the fetus
- inhale or ingest contaminated amniotic fluid
- spread thu umbillical vessels to the liver and hematogenously spread thru fetus
what are your 6 steps in diagnosing fetal loss?
- exaine the placenta for any abnormalities
- external examination of the fetus for evidence of fetal distress, congenial abnormalities, or skin lesions
- estimate the gestational age of the fetus
- determine the state of preservation at the time of expulsion
- determine if it was stillborn or a nonviable neonate
- do a routeine necropsy of the fetus
what is this?
a normal ruminant placenta
you see this during your examination of a placena. what is this?
amniotic plaques, they are foci of squamous epithelial cells and they are NORMAL, incicental finding
this is a cow placenta. what is this showing?
adventitial placentation, to compensate for inadequate placentomes, a NORMAL and INCIDENTAL finding (not placentitis)
you find this in a horse placenta. what is it?
a hippomane, collection of sediments, completely normal
when you see intercotyledonary and cotyledonary placentitis, consider what
bacterial and fungal causes first, esp brucella species, wear gloves!!
this is a bovine placenta. what is shown here?
necrotizing intercoyledonary and cotyledonary palcentitis caused by bacillus licheniforms
if you have an exaggerated cotyledonary cupping and a leathery appearance and infarction in a placenta, what should you suspect?
mycotic placentitis
this is a bovine placenta. what is shown here?
mycotic placentitis
if you have a cotyledonary placentitis with pinpoint foci of necrosis and mineralization you should think of
protozoal infection, esp toxoplasmosis in small ruminants
this is a sheep placenta. what do you suspect?
a protzoan infection with toxoplasma gondii
what is the cervical star in mares? why is it significant?
where the fetus should be exiting and there’s no nilli there so there’s also no endometrium there. the horse cervis is loose so placentitis is the most severe adjacent to the cervical star
this is a mare placenta. what is shown here near the green star?
bacterial placentitis, fibrin, edema, necrotic debris, the green star is the cervical star
the umbillical cord should be how long normally? in horses, what can happen if the umbillical cord is longer than this?
normally ,83cm, no more than 3-4 twists
long cords are prone to torsion which is a common non infectious cause of equine abortion
this is a horse fetus. what likely killed this fetus?
umbillical torsion due to long umbillical cord. you can see the congestion and edema
what is meconium and why is it important?
essentially it is babie’s first poo poo. when a fetus is distrssed from intrauterine hypoxia, meconium is released into the amnion and the fetus gasps/gulps and aspirates/ingests amniotic fluid into the lungs and abomasum respectively
what is wrong with this fetus besides the fact that it is dead
it has meconium staining on it’s skin, indicating fetal distress
this is the trachea of a fetus, what does this tell you?
there is meconium in the trachea indicating fetal distress, the fetus has aspirated it into the lungs
what can happen if a calf get’s stuck halfway through the birth canal? (dystocia)
there will be reduced venous and lymphatic drainage, leading to edema, congestion, and hemorrhage of the head and tongue
if you see fetal dermatitis or hyperkeratosis, what does that indicate?
a mycotic infection
this is a fetus head, what does this tell you?
mycotic infection of the fetus skin
why do we want to figure out the gestational age of a fetus when looking for a diagnosis?
different things kill fetuses at different points in gestaion, for example, neospora caninum will infect and cause abortions in calves mid gestation
why do we care about finding out the state of preservation at the time of expulsion of a fetus?
can suggest the type of condition
describe the difference between a fetus dying suddenly and a fetus dying slowly and how you would be able to see that
if a fetus dies suddenly, it doesn’t have time to signal to the cow and they remain in utero to cook for a while, when they are expulsed they are mummified and autolyzed
if a fetus dies slowly, it has time to initiate partution and they are expelled immediately and may be born dead or weak, but they are fresh at the time of expulsion
a fresh fetus is typical of what?
chronic disease and may be small for it’s age
an autolyzed fetus indicates what?
rapid fetal death usually from viremia, septicemia, or protozoal infections
if a fetus looks like this, what does this tell you about how it died?
it autolyzed so it died suddenly, from viremia, septicemia, or protozoal infection
if you have a mummified fetus, what does this tell you about how it died?
bacteria must be absent, aka no bacterial infections
can be viruses or protozoa still though, or even twinning
viruses such as parvo and enterovirus cause what in pigs?
stillbirth, mummifcation, embryonic death and infertility (SMEDI)
if you have a fetus that is macerated, what does this tell you about how it died?
bacterial infection is required for this to happen, so either the bacteria killed the fetus or the cervix was open and there was an ascencding infection
how can you tell between a stillborn fetus and a nonviable neonate fetus (aka, how can you tell if it was dead when it was born or if it died shortly after birth)
if the lungs are airated, the baby was alive and took a breath so it would be a nonviable neonate and not a stillborn
if there is hemorrhage, this means the baby was alive (dead animals do not bleed), so it would be a nonviable neoante and not a stillborn
what can cause goiter in a fetus?
iodine deficient diet, goiterogenic substances in the diet, genetic
what does it mean if the fetus you’re necropsying has a hemorrhagic tracheal cast? what about a fibrinous tracheal cast?
hemorrhagic cast: pathognomonic for trueperella pyogenes abortion in cattle
fibrinous cast: pathognomonic for equine herpesvirus 1 infection in mares
why should you always get a sample of the fetus’ lungs in a fetal necropsy?
the lungs are reflective of the amniotic environment and you will see a lot on histo even if you see nothing grossly
what is miliary hepatic necrosis?
where the liver looks like it’s been sprinkled with snow, indicitave of viremia or septicemia
in small ruminants, targetoid hepatic necrosis in a fetal liver is typical of
campylobacter infections
if a fetus has been infected with cache valley virus, what will they look like?
arthrogryposis (joint stiffness), and deformities of the spinal column and CNS
why do we want a sample of the brain to look at under histo in a fetus?
it is the target organ in protozoal infections
