Creeper condition in domestic fowl

CREEPER CONDITION IN DOMESTIC FOWL

  • Semi dominant lethal: (Incompletely dominant lethal, intermediate lethal)
  • In domestic fowl, an intermediate lethal gene when heterozygous gives rise to a peculiar condition called creeper.
  • The creeper chicken have short and crooked legs: they are unable to move normally and creep about without lifting their bodies off the ground.
  • The same lethal gene when homozygous causes death during the embryonic stages.
  • When two creeper chickens are crossed they yield a peculiar ratio of 2:1.

Creeper condition in domestic fowl

  • An explanation for the altered ratio can be found if we consider all the eggs which were incubated. One fourth of these failed to hatch which had dead embryos (at about 4th day of incubation).
  • Hence it is evident that creeper condition in chicken is a heterozygous expression of a gene which is lethal when homozygous.
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Last modified: Saturday, 23 July 2011, 5:54 AM