The Visual Guide to
Ovine Reproduction
Teratology: Congenital Anomalies
Ankylosis.
Generalized ankylosis of all joints in a newborn lamb. Unknown etiology. May have been associated with oligamnios leading to severely restricted fetal movement.
Eischen J (1975)
Arthrogryposis.
This arthrogrypotic lamb caused a dystocia and was delivered dead (note cloudy eye). Cache Valley virus was the probable cause, as the fetus was seropositive.
Smith MC (2006)
Anomaly with One Limb.
Rudimentary fetus with its own umbilical cord and one leg.
Smith MC (2006)
Atresia Ani.
Two-year old, recently purchased, pregnant Jacob ewe was examined for diarrhea. There was no anus to take her temperature. The terminal portion of the rectum exited into the dorsal vestibule. A recto-vaginal fistula could be palpated digitally.
Edmunds EE (2008)
Rectovaginal Fistula.
This 6 month old ewe lamb was born with atresia ani and a rectovaginal fistula which enables her to pass feces via the vagina.
Varsano S (2012)
Schistosomus Reflexus.
The abdominal wall is open and the vertebral column is reflected back on itself. The circulation is intact allowing the fetus to survive until birth. The cause of this developmental defect is unknown.
Smith MC (2006)
Schistosomus Reflexus.
The abdominal wall is open and the vertebral column is reflected back on itself. The circulation is intact allowing the fetus to survive until birth. The cause of this developmental defect is unknown.
Smith MC (2006)
Atypical Schistosomus Neonate.
Stillborn Dorset / Finn twin lamb. The abdominal wall is open and the viscera have prolapsed. The circulation was intact allowing the fetus to survive until term. Etiology unknown. The vertebral column appears to be normal [versus a classical Schistosoma reflexum].
Kane E (2011)
Atypical Schistosomus Neonate.
Congenital evisceration in a stillborn, term Dorset / Finn twin lamb. No hernial pouch. The edges of the opening were smooth and free from adhesions.
Kane E (2011)
Schistosomus Reflexus.
Total congenital evisceration in a stillborn lamb. Vertebral column is doubled back on itself. There are attached fluid filled amniotic membranes.
Dewar A (2012)
Unilateral Cryptorchid.
The right testicle is retained, the left one appears to be of normal size. Ram is in dorsal recumbency.
Smith MC (2006)
Intra-abdominal Testis - Close-up.
Small intra-abdominal testis and tail of the epididymis in a unilateral cryptorchid.
Smith MC (2006)
Cyclops.
Estimated 3-month old cyclopean fetal Dorset / Finn lamb. This malformed lamb is lying against the feet of a normal 4.5 kg lamb. It was delivered spontaneously along with a live normal twin. A single eye socket could be palpated.
Kane E (2011)
Cleft Palate.
If the cleft palate is not noted at birth it will soon be suspected when the lamb has milk coming out of its nostrils.
Smith MC (2006)
Palatoschisis.
The lower jaw has been removed to expose the roof of the mouth. There is complete failure of closure of the two sides of the palate.
Smith MC (2008)
Palatoschisis - Close Up.
Close-up of the roof of the mouth of a newborn lamb illustrating the lack of fusion of the palate. The nasal septum is clearly visible.
Smith MC (2008)
Agnathia Lateral View.
This lamb without a lower jaw was stillborn.
Smith MC (2006)
Agnathia Ventral View.
Ventral view of a stillborn lamb without a mandible.
Smith MC (2006)
Agnathia.
Overdue stillborn lamb with a small skull and without a mandible. Absence of a functional pituitary gland may have led to prolonged gestation. Long hair and large size suggest postmaturity. Congenital etiology.
Mogheiseh A (2013)
Agnathia Close Up.
Overdue stillborn lamb with a small skull and without a mandible. Absence of a functional pituitary gland may have led to prolonged gestation. Long hair and large size suggest postmaturity. Congenital etiology.
Mogheiseh A (2013)
Freemartin Lamb.
Normally, each lamb has its own separate placental circulation. Unlike in heterosexual cattle twins, freemartinism is an uncommon occurrence in heterosexual sheep twins [size of the tile is 15 cm square].
Smith MC (2006)
Freemartin Vulva.
Small underdeveloped freemartin vulva in the lamb on the left as a result of sharing placental circulation with a ram lamb, an uncommon occurrence in sheep. The newborn ewe lamb on the right is a singleton for comparison.
Smith MC (2006)
Male Hermaphrodite.
Prominent clitoris and small vulva of a male hermaphrodite. [intra-abdominal testes]
Shipley C (2006)
Male Hermaphrodite Genitalia.
Underdeveloped female tubular reproductive tract and a male gonad (an intra-abdominal testis and epididymis).
Mogheiseh A (2013)
Male Hermaphrodite Gonad.
An intra-abdominal testis and epididymis in a hemaphrodite ewe.
Mogheiseh A (2013)
Cystic Bile Duct.
Congenital malformation of the bile duct in a lamb. Due to the obstruction, the gallbladder is grossly distended.
Smith MC (2006)
Sheep-Goat Hybrids.
These fetuses died early in gestation due to immunologically incompatible placentation but were not delivered by the doe until approximately 5 months after breeding. Goats have 60 chromosomes, sheep 54. Fertilization occasionally occurs when a doe is bred by a ram, and rare births have been reported. When a ewe is bred by a buck fertilization rarely occurs.
Smith MC (2006)