Veterinary medicine

1. TERATOLOGY

2. DEFINITION
 Division of embryology or pathology that deals with abnormal
development and malformation of the antenatal individual
 Defined as science concerned with causes, mechanisms and signs
of structural or functional developmental deviations

3.  Few teratological defects commonly seen are
1. Hydrocephalus
2. Cyclopia or Cebocephalus
Anomalies of the trunk
1. Schistosomus reflexus
2. Campylorrachis scoliosa
3. Perosomus elumbis
4. Perosomus horridus
Embryonic duplication
1. Free monozygotic or dizygotic twins or triplets
2. Conjoined twins

4. HYDROCEPHALUS
 Head may be enlarged or normal in size, but section of head and
brain reveals distended ventricles.
 Characterized by birth of "dummy or bowler calves“ that are unable
to nurse properly and die in several days.
 The disease may be associated with hydramnios
 This may be due to a simple autosomal recessive gene
 Hydrocephalus is due to an abnormal accumulation of fluid in the
cranial cavity.

6.  Internal hydrocephalus
due to excessive fluid in the ventricular system
 External Hydrocephalus
rare condition
due to excessive fluid between the brain and duramater

7. CYCLOPIA OR CEBOCEPHALUS
 Characterized by a single orbit in which global tissue is absent or
rudimentary or in which eyeballs vary from single apparently
normal eye through all degrees of doubling to one consisting of two
complete but small adjacent globes

8. ANOMALIES OF THE TRUNK
 Schistosomus reflexus
 Most commonly seen in cattle, but may be observed rarely in sheep,
goat and swine. Characterized by a marked ventral curvature of the
spine so the occiput of the head lies near the sacrum.
 Body and chest walls are bent laterally and dorsally and thoracic/
abdominal viscera are exposed
 Pelvis is deformed
 Liver is abnormal in shape and cystic
 Rumen is occasionally distended
 Limbs are ankylosed and rigid

11.  Campylorrachis scoliosa
 Fetal monster occurring rarely in cattle and swine
 Characterized by lateral curvature of spine
 Limbs are usually deformed and ankylosed

12.  Persomus elumbis
 Occasionally seen in cattle, pig, sheep and dog
 Characterized by a lack of vertebrae and spinal cord caudal to the
thoracic region

13.  Persomus horridus
 Bovine fetal monster with generalized severe ankylosis and muscle
contractures
 Arrow indicating double “S” shaped vertebral column

14. EMBRYONIC DUPLICATION
 Free monozygotic or dizygotic twins or triplets
1. Symmetrical twins are either monozygotic or identical or dizygotic or
fraternal
2. Asymmetrical twins consists of a normal twin and a monster
e.g. Holocardius amorphus or amorphus globosus

15. AMORPHUS GLOBOSUS
 Occasionally seen in cow, but also in mare, ewe and goats
frequently attached to the placenta of the normal twin
 It is an imperfect zygote of dizygotic twins and parasitic upon the
placenta of the normal twin and are never observed in single births
 Amorphus globosus usually appears as a round or oval edematous
structure covered with skin and hair and containing connective
tissue, fat and ocassionally cartilage and bone

16. Amorphus globosus fetus with exposed
intestinal loops and appreciable footprints
of liver development

17.  Conjoined twins
 Arise from single ovum and are monozygotic
e.g. Monocephalus Thoracopagus Tetrabrachius Tetrapus Dicaudatus
monster