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Israel Journal of Veterinary Medicine  Vol. 69 (2)  June 2014 Berlin, D. 92
INTRODUCTION
Prematurity in foals is a well recognized problem encoun-
tered by equine practitioners. It is usually marked by in-
complete development of diferent organs and physiologi-
cal functions. Normal gestation length in mares has a very
wide range. Several studies investigated diferent breeds and
diferent factors afecting this period. Te acceptable mean
gestational length in mares is 340-345 days with a normal
range of 320-370 days (1, 2, 3), although other studies have
shown a range as wide as 315-388 days (4). Nevertheless, an
acceptable defnition of prematurity in foals is having less
than 320 day’s gestational age (1). Foals born before 320 days
of gestation are usually given an unfavorable prognosis for
survival (5). Te main problems, which limit the survival of
premature foals, are lack of full maturity of the respiratory,
gastrointestinal and nervous systems and defcient homeo-
stasis function that afects the adjustment to the environment
outside the uterus. Other problems include various limb de-
formities, low birth weight, thin hair coat and weak suckle
refex (1,2). Reports of premature viable foals born before
300 days of gestation are very scarce (6). Te case presented
hereby describes the spontaneous delivery of a viable flly
at 280 days of gestation, the management, treatments, and
complications she had endured as well as the fnal outcome.
A Filly Born At 280 Days of Gestation: Management, Complications
and Final Outcome
Berlin, D.
Koret School of Veterinary Medicine, Te Hebrew University of Jerusalem, Israel.
* Corresponding Author: Dr. Dalia Berlin,Veterinary Teaching Hospital, P.O. Box 12, Rehovot 76100, Israel. Tel: 054-8820675, Fax: 03-9688525.
Email: dalia.berlin@mail.huji.ac.il.
ABSTRACT
A mix breed flly was born after only 280 days of gestation in a spontaneous delivery. Te flly was small, had
a weak suckle refex, very thin hair coat, severe tendon laxity and carpi valgus but was bright and alert and
without respiratory difculties. Te flly was treated with plasma and prophylactic antibiotics and was fed
via an indwelling naso-esophageal tube until she was able to suckle from the mare at the age of 2 weeks. Te
cause for the premature parturition was not determined, however, placentitis was highly suspected due to the
apparent precocious in utero maturation of the flly that allowed for her survival without severe complications
during the neonatal period. Te flly consequently sufered from a traumatic fracture of the third metatarsal
bone in the left hindlimb at the age of 3 weeks, which was treated conservatively with external fxation
and healed. As a yearling, she developed severe degenerative joint disease in the left shoulder joint which
was attributed to osteochondral changes that may have been related to her prematurity. Te degenerative
changes and chronic severe left forelimb lameness resulted in severe angular limb deformities in both front
limbs which eventually led to the euthanasia of the flly at the age of 2.5 years. Tis case may suggest that
severe developmental orthopedic deformities may be a late sequel of prematurity that may eventually hinder
the long term survival.
Keywords: Foal, Premature, Placentitis, Developmental Orthopedic Diseases, Angular Limb
Deformity.
Israel Journal of Veterinary Medicine  Vol. 69 (2)  June 2014 93 Premature Filly
CASE REPORT
A 6-year-old mixed-breed mare of unknown parity gave
birth to a live flly at 280 days of gestation (August 9
th
2005
to May 16
th
2006). Te presence of the pregnancy was frst
confrmed by transrectal ultrasound on day 19 post breeding
and again at 80 days of gestation. A few days prior to partu-
rition, the mare developed a full size udder and on the day
of delivery, milk dripping was observed. Te owners did not
report any problems with the mare during the pregnancy.
Te parturition was uneventful and was witnessed by the
owners. Te flly stood up but did not suckle from the udder
and thus was given a small amount of milk through a bottle.
Te attending practitioner (the author) was summoned 8
hours after parturition to treat the flly. Te placenta was dis-
carded by the owners and was not available for examination.
Te flly was very small and lean, with very thin silky hair
coat; she had severe tendon laxity of all four limbs, valgus in
both carpi, reddish colored tongue and a weak suckling refex.
Nevertheless, she was bright and alert, was able to stand up
unassisted and her head was not domed shaped. Tere did
not seem to be any respiratory distress but the owners were
informed of the unfavorable prognosis for survival. Due to
fnancial constraints, the flly was not referred to an intensive
care facility for further treatment and remained at the care
of the owners. Te mare had a fully sized udder with abun-
dant milk production; however, the colostrum seemed to be
of poor quality or nonexistent on gross examination (white
and dilute milk). Te flly received 2 liters of equine fresh fro-
zen plasma intravenously, and was treated with broad spec-
trum antibiotics (procaine penicillin, Norocillin Veterinary,
Norbrook Laboratories Ltd., Newry, Ireland. 20,000 U/kg
bwt, intramuscularly, twice daily) and gentamicin, Gentaject
50, Eurovet Animal Health BV, Bladel, Netherland, 6.6 mg/
kg bwt, intramuscularly, once daily). Furthermore a small
diameter indwelling naso-esophageal feeding tube (12 Fr,
108 cm. MILA international Inc., Erlanger, Kentucky, USA)
was inserted with endoscopic guidance. Te forelimbs were
put in full limb thick bandages and plastic splints were ap-
plied to the palmar aspect to treat the carpi valgus (suspect-
ed incomplete ossifcation of the small carpal bones). Soft
bandages were applied to the hindlimbs in the pastern and
fetlock regions to protect the skin against abrasions as a re-
sult of the tendon laxity (Figure 1). Te flly was fed the
mare’s milk hourly through the feeding tube in increasing
amounts. Because of the very thin hair, the skin was exposed
to abrasion and at the end of the frst day numerous superf-
cial skin wounds had developed. Tese were treated topically
with silver sulfadiazine cream (Silverol, Teva Pharmaceutical
Industries Ltd., Petah Tikva, Israel). Te flly seemed to be
oversensitive to touch and would not tolerate being covered
to protect her skin and body temperature. Meconium and
urine were passed without incidence.
After 5 days of steady improvement in strength and
suckle refex, while the flly was being fed by both bottle
suckling and through the feeding tube, there was a sudden
deterioration in her condition. She was slightly dehydrated
and weak and urine was seen dripping from the umbilicus.
After inquiry of the owners it appeared that the main cause
for the dehydration was mistaken under-feeding. Blood was
obtained for complete blood count. Te only abnormality
was leukocytosis (22.4x10
3
Leukocytes/µl, reference range
6-13x10
3
Leukocytes/µl) with slight neutrophilic toxicity
on the blood smear. With increased feeding her condition
quickly improved. Povidone iodine solution (Polydine solu-
tion, Ben Shimon Floris Ltd., Misgav, Israel. 1%) was applied
daily to the umbilicus and the urine dripping stopped after
5 days. Gentamicin was discontinued after 9 days and pro-
caine penicillin after 14 days when most of the skin wounds
had healed.
On day 12 the flly started suckling from the mare and
was gradually weaned from the bottle. On day 14 she was
completely self reliant for feeding. Te bandages on the fore-
Figure 1: Te flly at the age of 9 days. Notice the small body size compared to
the dam, the hindlimb laxity and the splinted forelimbs.
Case Reports
Israel Journal of Veterinary Medicine  Vol. 69 (2)  June 2014 Berlin, D. 94
limbs were changed every 3-4 days and the splints were
gradually removed after 14 days at which time the valgus
and laxity had resolved. At this time her body condition im-
proved with noticeable muscle mass gain and she weighed
25 kg.
When the flly was 23 days old the mare accidentally
stepped on her left hindlimb. Physical examination and ra-
diographs revealed a transverse non-comminuted fracture in
the diaphesis of the third metatarsal bone with a 2 cm skin
laceration located 4 cm proximal to the fracture line. Again,
due to fnancial constrains, surgical repair of the fracture was
declined by the owners. Te wound was copiously lavaged
with saline and routinely sutured. Under short general an-
esthesia, the fracture was reduced to near normal alignment
and a thick bandage with dorsal and plantar plastic splints
were placed distal the tarsus. Te flly was treated with cepha-
lexin (Cefovit forte, Vitamed Ltd., Binyamina, Israel. 20 mg/
kg bwt, per os, three times daily), gentamicin (6.6 mg/kg
bwt, intramuscularly, once daily), phenylbutasone (Eliezer
Linevitz Ltd., Even-Yehuda, Israel. 2.2 mg/kg bwt, per os,
once daily) and tetanus antitoxin 1500 U intramuscularly
(Fort Dodge, Overland Park, KS, USA). Te flly was able to
bear weight comfortably on the splinted leg and was kept in
stall rest. Te bandages were changed once a week. Te frst
4 bandage replacements were conducted under heavy seda-
tion to prevent movement and displacement of the fracture.
After initial fracture stability was clinically achieved, ban-
dages were replaced without sedation. Tere was no evidence
of wound infection and the sutures were removed after 14
days. Gentamicin was discontinued after 13 days. Cephalexin
was discontinued initially after 13 days but was reintroduced
after 9 days to treat two pressure sores that developed on
the medial and lateral aspects of the fetlock. Te cephalexin
treatment was discontinued after additional 14 days.
Fifty two days after the injury, the leg seemed to be stable
and follow up radiographs showed a large callus around the
fracture with some bone flling of the fracture line; however,
there did not seem to be enough healing to allow removal
of the splints. In the following weeks, the bandages were re-
placed every 7-10 days, the pressure sores healed and a sin-
gle plantar splint was applied. After additional 52 days (3.5
months from the injury), follow up radiographs were taken.
Te callus looked smaller, more than 50% of the fracture line
was flled with new bone and there was better alignment of
the two fragments. At this stage, severe fexural laxity had
developed due to the long term limb fxation, therefore, the
bandages and splint were gradually removed over the next
4 weeks at which time there was marked improvement in
the laxity and the flly was able to walk and trot without
lameness.
OUTCOME
Te flly continued to grow and develop at a rate that was
compatible with that of another flly residing in the stable,
which was of the same age, although she did seem to be
somewhat smaller than expected from the size of her parents
and her age. Left forelimb lameness at the walk was noticed
at the age of 12 months. No improvement was seen with
rest and phenylbutazone treatment and she was referred
to the Koret School of Veterinary Medicine – Veterinary
Teaching Hospital (KSVM-VTH) for further diagnosis.
Physical examination, peripheral nerve blocks and intra-ar-
ticular anesthesia localized the source of the lameness to the
left scapulohumeral (shoulder) joint. Radiographs revealed
joint dysplasia, fattened gleoid cavity surface, irregular joint
surface and osteophytes in the distal scapula. In addition,
physitis with new bone formation was observed in the head
of the humerus (Figure 2). Diagnosis of severe degenerative
changes caused by several developmental osteochondral ab-
Figure 2: Medial to lateral radiograph of the left shoulder joint taken
under general anesthesia at the age of 12 months at the KSVM-VTH.
Te black arrow indicates the osteophytes in the distal scapula, the
white arrow points at the physitis with abnormal bone production
in the head of the humerus and the arrow heads indicate the joint
incongruity and irregular joint space.
Case Reports
Israel Journal of Veterinary Medicine  Vol. 69 (2)  June 2014 95 Premature Filly
normalities was made which warranted a guarded progno-
sis. Te joint was injected with sodium hyaloronate (51 mg)
(HY-50, Bexco Pharma Inc., Mississauga, Canada), triam-
cenolone (Trigon, Bristol-Myers Squibb, Madrid, Spain. 20
mg) and amikacin (250 mg, Amikacin-Fresenius, Bodene
(PTY) Ltd., Port Elizabeth, South Africa). Temporary clin-
ical improvement was observed, however, within 2 weeks
the lameness resumed and gradually worsened. In the fol-
lowing months, as the lameness continued, severe angular
limb deformities developed in both forelimbs with superf-
cial and deep digital fexure tendons contraction combined
with fetlock and carpi varus, which was most severe in the
right front leg (Figure 3). Te flly was eventually euthanized
at the age of 2.5 years due to the severe lameness and limb
deformities.
DISCUSSION
To the best of the author’s knowledge, this is the frst detailed
published case report of a viable foal born after only 280 days
of gestation. Conventionally, a foal born with less than 320
days of gestation is considered premature with the complex
problems associated with this condition (1). Occasionally,
foals born between 300 and 320 gestation days can be rela-
tively normal if early maturation occurs in utero (2, 7, 8).
Rossdale and Silver (6) reported a viable foal born after 281
days of gestation to a mare that sufered from placentitis,
however, no data was provided except for the physical and
hematological parameters, the response to ACTH stimula-
tion at the age of 12 hours, and the fact that the foal had
survived the neonatal period.
Te flly described here had many of the physical char-
acteristics of prematurity such as low body weight, silky hair,
severe laxity of limbs and ears, angular limb deformities, red
colored tongue and a poor suckle refex. Other, more debili-
tating characteristic features, were not observed. Tere was
no respiratory distress at any point, no gastrointestinal abnor-
malities and there did not seem to be any severe endocrine or
metabolic abnormalities (although specifc diagnostic blood
tests were not conducted). Moreover, although she did not
receive colostrum in the frst few hours and plasma treat-
ment was delayed for more than 8 hours, she did not show
any signs of severe infection or sepsis. Te development of
umbilical urine dripping, evidence of a patent urachus, on day
5 was probably caused by localized infection and not a sign
of generalized infection or sepsis since the urine dripping
resolved within 5 days and no other organs showed signs of
infection (9). It may be concluded that the main reason for
the flly’s survival, besides the supportive treatment and the
owners’ devoted commitment, was that there was sufcient
accelerated and precocious in utero maturation preceding the
early parturition.
Causes of spontaneous premature parturition in mares
include placental infection (placentitis), placental insuf-
ciency, placental edema or premature separation, twinning,
systemic illness of the mare and other causes of stress such
as general anesthesia (2, 10). Premature udder development
and lactation, with consequent early parturition are char-
acteristics of placentitis. Other clinical signs of placentitis
include vaginal discharge and rarely abdominal discom-
fort and fever (8, 11). Although the owners did not ob-
serve any abnormalities during the pregnancy and ultra-
sonographic evaluation of the placenta was not conducted
during the later stages of the pregnancy, placentits was the
most likely cause for the premature parturition in this case.
Live foals born to mares afected by placentitis are com-
monly born weak and unthrifty and may develop sepsis
or hypoxic ischemic encephalopathy (“dummy foal”) (11).
Contrary to these compromised foals, the unfavorable in-
tra-uterine conditions caused by the infection and infam-
mation due to placentitis have been shown to prompt early
maturation of the hypothalamus-pituitary-adrenal axis and
Figure 3: Te flly at the age of 23 months. Notice the fetlock joint varus
and fexural contracture in both forelimbs, more severe on the right side.
Case Reports
Israel Journal of Veterinary Medicine  Vol. 69 (2)  June 2014 Berlin, D. 96
of lung function in the fetus and this accelerated develop-
ment may have accounted for the described flly’s post par-
turient thrive and survival (2, 6, 7, 11, 12). Unfortunately,
the placenta was discarded after parturition and was un-
available for examination, thus, defnitive diagnosis of pla-
centitis was not achieved.
Te left forelimb lameness that the flly developed as
a yearling was attributed to the complex of developmen-
tal orthopedic diseases (DOD) (13) or the newly defned
Juvenile osteochondral conditions ( JOCC) (14). Te radio-
logical abnormalities could be attributed to osteochondri-
tis dissecans (the fattened gleoid cavity surface, irregular
joint surface and the osteophytes in the distal scapula). Te
new bone production in the humeral head was most likely
due to severe and chronic physitis. Developmental disorders
(DOD or JOCC) of the shoulder joint are well recognized
in weanling and yearling foals (13, 14, 15). Te abnormal
cartilage and subchondral bone development results in an
abnormally shaped humeral head and glenoid cavity contour
which cause joint instability and lead to secondary degenera-
tive changes. Suspected causes for DOD/JOCC are rapid
growth, dietary imbalances, trauma, under or over exercise
at a young age, anatomical abnormalities and genetic pre-
disposition (15, 16, 17). Excessive loading of the forelimbs
due to the hindlimb fracture in the described flly is a pos-
sible but not very likely cause for the forelimb lameness
since the hindlimb injury occurred several months prior to
the appearance of the forelimb lameness. In addition, the
flly was not severely lame throughout the recuperation pe-
riod with the aid of the hindlimb external fxation. One of
the above factors could have been the cause of the DOD
in the described flly, however, a causal relationship to her
prematurity may be suspected as well. Prematurity has not
been previously regarded as a predisposing factor for abnor-
mal cartilage and subchondral bone development leading
to osteochondritis dissecans or other DODs. Nevertheless,
this case may suggest that the abnormal pressure and stress
applied to the incompletely developed joints as a result of
the “unscheduled” and premature weight bearing could be
a contributing factor. Te severe laxity and the carpi valgus
that were observed at birth and were related to the prema-
turity (18), although treated and resolved, may have been
contributing factors as well.
Te acquired angular limb deformities that developed at a
later stage were most likely as a result of the chronic left fore-
limb lameness that caused overloading of the contra-lateral
limb and abnormal weight-bearing in the afected limb (19).
Te combination of the refractory left forelimb lameness and
the severity of the acquired limb deformities indicated a poor
prognosis and the flly was eventually euthanized. Although
the flly survived the neonatal period without severe com-
plications related to her prematurity, the possibility of as-
sociation between the prematurity and the development of
the severe later skeletal abnormalities indicate that owners
should be advised of potential long term complications for
premature foals that are not noticed at birth or in the neo-
natal period.
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Case Reports