No abstract

A radio telemetry system was used to establish a deep body temperature cycle in a domestic male and a female fowl under continuous light of constant intensity. Certain sex differences were noted. In the female, the maximum body temperature was reached at time of oviposition. There were two peaks in temperature during the daily temperature maxima in the animal, which laid an egg the next day. Oviposition may account for one peak and ovulation the other. The female had a 28-hr cycle and the male a 24-hr cycle. The data were evaluated by autocovariance, power spectral analysis, harmonic regression, and other methods.

No abstract

The design of telemetry systems for chronic implantation within the body have progressed from simple single-channel devices to complex multichannel systems over the last 15 yr. Although chronic measurements of temperature, ECG, and pressure have been reported with good results, measurements such as dimension and blood flow have been difficult because of heavy power requirements. The design to be described is a multiplex system that will measure up to eight individual parameters simultaneously, including blood flow. Flow is measured using an electromagnetic transducer, and by special design, the normal high power requirements of the electromagnetic technique have been reduced to a few hundred milliwatts. The system is powered by two NiCad, rechargeable batteries which are periodically recharged through the intact skin by induction at 250 kHz to an implanted pickup coil. The presently constructed units have been configured to measure ECG, two pressures, temperature and ascending aortic flow.