Egg turning angle and prequency impact on embryo position

In a co-operative project between the universities of Ankara, Turkey and North Carolina State, USA, it was concluded that the incidence of malpositioned embryos was increased by a reduced turning angle. However, the effects was ameliorated by increasing the frequency of turning. The work was reported by Drs Elibol and Brake.

Two experiments, each comprising two trials, were carried out to determine if a turning angle of less than 45^o from vertical could be succesful in terms of the number pf malpositioned embryos, i.e. with the head at the narrow end of the egg.

Hatcing egg from commercial broiler breeders flocks aged 55-61 weeks were turned at angles of 35^o, 40^o, or 45^o degrees every hour for 18 days in experiment 1. Turning angle had no effect on fertile hatchability but the incidence of mapositioned embryos was higher in the eggs turned at 35^o degrees than with the other treatments.

In experiment 2, egg were subjected to turning angles of 35^o and a turning frequency of every 60 or 15 minutes, or 45^o every 60 minutes. This time, turning angle and frequency had no effect on fertile hatchability or embryonic mortality. However, the incidence of malpositioned embryos was higher in the group turned with a 35^o angle hourly than with the other treatments.