Analysis of Ovulation-Oviposition Patterns in the Domestic Fowl by Telemetry Measurement of Deep Body Temperature

Abstract

Continuous temperature records in relation to time of oviposition and behaviour associated with it are summarized for 13 laying strain pullets with a regular pattern of oviposition and for a further 10 pullets which were either 'internal layers' , or natural or induced layers of membranous-shell eggs. The records of five pullets, in which the most recently ruptured follicle was excised within 2-5 h after ovulation, and of four control pullets are also included.The previously reported finding that a temperature peak normally occurs at oviposition is confirmed. However, no evidence could be found for the regular occurrence of twin temperature peaks (for ovulation and oviposition), or for other direct temperature indicators of time of ovulation.The 'oviposition' temperature peak is always accompanied by characteristic pre-laying behaviour, even in the absence of the oviposition due to occur at that time. Like the pre-laying behaviour, the temperature peak is shown to be a consequence of the ovulation event of the previous day; more precisely it is shown to depend on the presence of the intact ruptured follicle from which the ovum was shed.It is concluded that the timing of a sequence of ovulations may be inferred, therefore, from the pattern of temperature peaks and this method is being used to study unusual ovulation-oviposition patterns occurring in some of our selection lines.Some preliminary observations are also reported on the effects of injection of oxytocin, vasopressin or progesterone on body temperature.