A Preliminary Study on the Hatchability of Chicken Eggs Subjected to Shaking Agitation1

PIVOTAL displacement or "turning " is a purely physical factor, necessary during incubation for the normal develop-ment and hatchability of all domestic fowl embryos. In order to provide the re-quired stimulus, modern commercial in-cubators are so constructed that the trays of eggs can be tilted back and forth through a 90 degree arc (i.e., 45 degrees each way from horizontal). It is common procedure to candle the eggs and transfer them to hatching trays on the 18th day. If shaking agitation could be substi-tuted for conventional turning, several advantages would ensue: (1) eggs could be incubated and hatched in the same tray; (2) labor costs resulting from the 18-day handling would be eliminated; and (3) incubator space could be utilized more efficiently. There are, however, several experi-mental observations recorded in the literature which counsel against the work-ability of such a scheme. Stiles and Wat-terson (1937) described in rather complete detail the effects of jarring on developing embryos. A 490 gm. weight was dropped a distance of 6 cm. onto a table top upon which the incubator rested. The shocks were delivered at the rate of 15 blows per minute at 15 minute intervals. Only one chick was hatched from 155 eggs s