Temperature is the most important among several factors that are needed for optimum avian embryonic development during incubation. Previous studies have implied that incubation temperature may have an impact on chick quality and post hatch performance. The use and accuracy of different methodologies for the estimation of embryonic temperature and eggshell conductance values during incubation were determined in three trials. Results suggested that air cell temperature using transponders may be used for the estimation of embryo temperature from 12 through 19 days of incubation and the subsequent calculation of eggshell conductance and specific eggshell conductance values. A final trial was conducted to further substantiate the estimation of embryo temperature using air cell readings by implanting probes alongside transponders in the air cell. It was determined that further modifications are needed to perfect this particular method.

Avian embryonic development, hatchability, and post-hatch performance are greatly affected by temperature. Therefore, a pragmatic, minimally invasive, and industrially applicable method for the precise and accurate measurement of embryonic temperature is needed. The objective of this research was to develop such a method. Preliminary research concerning air cell depth profiles and the relationships of eggshell thickness to thermal gradients across the shells of broiler hatching eggs were determined. This provided information for appropriately positioning and timing wired thermistor probe insertion into egg air cells for the practical and accurate estimation of embryo temperature. The relationship between air cell temperature readings using transponders and wired thermistor probe network assemblies were likewise determined. Embryo temperature estimation using probes was shown to be a satisfactory, but their depth should be adjusted daily by 0.042 cm after Day 12 of incubation in order to mirror transponder temperature readings.