Teratogenic Effects of Plants on Lambs

1
Teratogenic Effects of Plants on Lambs

• Jess Russ
• Chase Constant

2
Case Summary

• Lambing problem in Spanish Forks, Utah
• Drought kept herds on mountain pastures later
  into fall breeding season
• Rancher described the following in lambs
• Distorted upper jaw, cleft palate, and cyclopia
• Motor-nerve paralysis
• Surviving lambs had shortened legs

3
Cyclopia in lambs
4
Possible Causes

• Two toxic plants were found on the pasture land
• Veratrum sp. (commonly known as Corn Lily)
• Lupinus sp. (Lupine)

5
Veratrum sp.

• Contains 3 teratogenic alkaloids
• jervine, cyclopamine, and cycloposine
• Inhibits proteoglycan synthesis resulting in
  defective chondrongenesis
• results in head, trachea, and bone malformations
• Cyclopamine and jervine inhibit Shh signaling
  during gastrulation-stage

6
Teratogenic Effects of Veratrum sp.
 
Day of Gestation Effect
14 cyclopia
17-18 motor-nerve paralysis of hind legs
12-30 cleft palate, harelip and brachygnathia
30-36 shortened legs from hypoplasia
 
7
Lupinus sp.

• Contains the toxic alkaloid anagyrine
• Ewes may be symptomatic with the following
• salivation, ataxia, seizures, and head-pressing
• The alkaloid is NOT teratogenic to sheep fetuses
• Causes crooked calf syndrome in cattle

8
Lupine Effects in Cattle

• Cow rumen metabolizes anagyrine resulting in a
  teratogenic derivative
• Causes an immobilizing effect on fetus
• Fetus malformations occur because the fetus
  remains in one position for a prolonged period
• Occurs when exposure is 40-70 days in gestation

9
Diagnosis

• The symptoms that the rancher noted were
  indicative of the toxic Corn Lily
• The Lupine, while toxic to sheep, was not the
  underlying cause of the noted problem

10
Management Suggestions

• Keep ewes in their first trimester off the
  problematic pastures
• No treatment options are available

11
(No Transcript)
12
References

• Chan A, Downs D, Tsai C, Begley B, Triplett J.
  Poisonous Plants. http//cal.vet.upenn.edu/poison/
  plants/ppweste.htm. University of Pennsylvania.
  2006 Apr. 19.
• Lee ST, Panter KE, Gaffield W, Stegelmeier BL.
  Development of an enzyme linked immunosorbent
  assay for the veratrum plant teratogens
  cyclopamine and jervine. J Agric Food Chem. 2003
  Jan 2951(3)582-6.