Length of Survival of Homozygous Creeper Fowl Embryos

Abstract

Eggs from Creeper matings were started in a still-air incubator at 96[degree]F and transferred to standard conditions of a forced-draft incubator at 99[degree]-100[degree]F after 12, 24 and 48 hrs., respectively. Control eggs were incubated throughout in the same forced-draft incubator. When the low temp. lasted 24 hrs., there was a 170% rise in the frequency of survival of homozygous embryos as compared with the controls. Increase of low temps. to 48 hrs. caused a disappearance of this survival advantage.