Foaling can be an event that is equal parts exciting and nerve wracking
for novice and experienced horse owners alike. Every owner should be aware
of the events of a normal foaling, as well as complications that can arise. One
such complication that is an extreme emergency is premature placental separation, or “red bag delivery.” This complication makes up 5-10% of all abortion,
stillbirth and perinatal death cases in horses.
In a normal foaling, the chorioallantois (the outer placental membrane that
attaches to the uterus) ruptures and releases allantoic fluid—the horse’s “water
breaks.” After this, a thin, clear membrane, called the amnion or water bag (the
inner membrane of the placenta that surrounds the foal and contains amniotic
fluid) will emerge from the vulva and as labor progresses the foal’s front feet and
nose should be visible inside the bag. In a red bag delivery, the chorioallantois,
which is a velvety dark-red color, prematurely separates from the uterine wall
and protrudes through the vulva. This causes a dangerous decrease in oxygen
transport to the foal and the foal can suffer from hypoxia (lack of oxygen) and
may even die of asphyxiation if the condition is not corrected quickly.
NOT the Season’s Hottest
Accessory, but…a Foaling Emergency!
By Ashley Miller, DVM Student (Class of 2015)
Edited by Dr. Teresa Buchheit, DVM, MS, Dipl. ACVIM,
Purdue Equine Community Practice
Dr. Teresa Buchheit joins the Purdue Equine
Community Practice from North Carolina.
She was born and raised in Chesterton, IN and
decided to become a veterinarian when she was
just 7 years old. She obtained her DVM from
Purdue University in May of 2005.
Teresa completed an equine medicine and
surgery internship at the Mississippi State
University Animal Health Center and went
on to complete a large animal internal medicine residency at the University of Tennessee
Veterinary Medical Center. In February 2010
she earned board certification in Large Animal
Internal Medicine by the American College of
Veterinary Internal Medicine.
After the residency, Teresa spent almost a year
working as an equine practitioner in a private
practice in Eastern Tennessee before returning
to academia to complete a Master’s of Science
at North Carolina State University, where her
research interests were in equine sepsis and
systemic inflammatory disease.
Teresa’s professional interests include neonatal
medicine, neurology, and endocrine/meta-bolic disorders; although, she enjoys all facets
of equine practice. She also has an interest in
When not working as a veterinarian, Teresa
spends most of her time enjoying the outdoors
with her husband and their Labradors. Teresa
also is involved with raising future assistance
dogs for a national service dog organization,
Canine Companions for Independence.
News & Notes
Dr. Teresa Buchheit
A Red Bag:
Veterinarians should educate their clients on what to do if this condition
occurs. Owners and those assisting with foalings should be instructed to have
on hand a sharp, clean instrument (such as scissors or a knife) to immediately
open the red placental membrane. The veterinarian’s number should be kept
handy and called once the bag is opened and the foal should be delivered as
soon as possible. If available, the newborn foal should be supplemented with
oxygen as quickly as possible after delivery. Owners should continue to keep a
close eye on the foal, as these foals can develop delayed signs of hypoxia even
though they may appear normal at birth.
The causes of premature placental separation in the mare are many. Premature placental separation can occur with placental infections (placentitis),
fescue toxicity, death of a fetal twin or when an abortion is about to happen.
If an abortion is imminent, the delivery of the aborted fetus can be assisted to
prevent a dystocia. If the cervix is closed and the fetus is still alive, progesterone
and flunixin meglumine (Banamine®) therapy may permit the pregnancy to be
carried to term. Antibiotic therapy should be started systemically if placentitis
Owners should monitor all pregnant mares closely and contact their
veterinarian if an abnormality is detected. Recognition of a red bag delivery
and immediate intervention are key factors for survival of the foal.
Normal – amnion
emerging from vulva
Abnormal – chorioallantois
emerging from vulva
Red Bag Image: http://www.miniatureventures.com/redbag1.jpg
Amnion Image: https://www.azpinarabians.com/images/Amniotic-membrane_B.jpg
Brinsko, S. et al. Manual of Equine Reproduction. 3rd Edition. 2011.
McCue, P. Red Bag – A Foaling Emergency. CSU Equine Reproduction Laboratory.