Chondrodystrophy: an inherited lethal condition in turkey embryos.

Chondrodystrophy was found to occur as an embryonic lethal in a special line of turkeys. Inheritance of the condition was studied in embryos produced parthenogenetically from virgin dams and also in embryos from the same dams in bisexual matings. Expression was similar to other forms of the disorder encountered in various avian species. Micromelia and brachycephaly were recognized in affected embryos after 9 days while lethality occurred mainly after 16 days of incubation. A few affected embryos expressed modified phenotypes and these were also nonviable. Modified phenotypes were not observed in parthenogenetic production, and it was thus inferred that such embryos may have been heterozygotes. No changes were evident when the genetic background was altered. The condition was inherited as a single, autosomal, recessive lethal, in both parthenogenetic progeny and in progeny from bisexual matings. The symbol ch is designated for the mutant allele.