Abstract: The invention herein consists of apparatus and a method of monitoring livestock for artificial insemination purposes. A transmitter is fastened to the female animal to generate a signal which is received at a distant point and recorded for interpretation of the phase of the animal's fertility cycle. The transmitter includes time delay circuitry which causes the transmitter to pause for a predetermined time before signal generation. Switch means when closed activates the transmitting means and cut-off means within the transmitter terminates its activities after signal generation to conserve energy.In the preferred embodiment of the invention a magnetic switch is employed and a time delay circuit in the transmitter allows approximately 15 seconds to elapse before signal generation. The receiving unit of the preferred embodiment includes a standard receiver and a microprocessor.