A study of the effect of egg separation on hatching time and of the source of clicking sounds in the embryo of the domestic chicken

Publisher Website
Google Scholar
Abstract
The phenomenon of synchronized hatching was studied in a two-part investigation using White Leghorn and Rhode Island Red embryos and chicks. Experiments were conducted to test for the effect of separating eggs on hatching time and to locate the source of clicking sounds emitted by embryos during the final hours of incubation.A total of 25 eggs separated by no less than 4 in. and five clutches, each with 10 eggs in contact, were incubated and their hatching times compared. There was no difference in the mean hatch times of separated versus contact eggs. Separated eggs, however, were more variable in their hatch times than contact eggs, a statistical analysis showing a significant difference at the 0.05 level.Recordings were made of audible activity produced by embryos from their 17th day of incubation, and of hatched chicks up to 2 days after hatching. Clicking sounds from within the embryos were heard from 2 to 7 h after pipping (first puncture of the egg shell) had occurred. The source of the clicking was associated primarily with the right abdominal air sac and possibly with the right posterior thoracic air sac of the respiratory system. Other observations are described.
Keywords

This publication has 1 reference indexed in Scilit: