Abstract: A method for continuous measurement of differences in gas concentrations, comprises providing at least first and second gas analyzers, connecting a stream of incurrent fluid to a chamber containing an animal, withdrawing air from the chamber to form a stream of excurrent fluid, taking first subsamples of the excurrent fluid in a first subsampler, taking a subsample of the incurrent fluid in a second subsampler, alternately providing excurrent fluid from the first subsampler to the first gas analyzer and to the second gas analyzer to measure the gas concentrations in the excurrent fluid, and alternately providing incurrent air from the second subsampler to the first gas analyzer and to the second gas analyzer to measure the gas concentrations in the incurrent fluid.

Abstract: A method for continuous measurement of differences in gas concentrations, comprises providing at least first and second gas analyzers, connecting a stream of incurrent fluid to a chamber containing an animal, withdrawing air from the chamber to form a stream of excurrent fluid, taking first subsamples of the excurrent fluid in a first subsampler, taking a subsample of the incurrent fluid in a second subsampler, alternately providing excurrent fluid from the first subsampler to the first gas analyzer and to the second gas analyzer to measure the gas concentrations in the excurrent fluid, and alternately providing incurrent air from the second subsampler to the first gas analyzer and to the second gas analyzer to measure the gas concentrations in the incurrent fluid.

Abstract: A method for continuous measurement of differences in gas concentrations, comprises providing at least first and second gas analyzers, connecting a stream of incurrent fluid to a chamber containing an animal, withdrawing air from the chamber to form a stream of excurrent fluid, taking first subsamples of the excurrent fluid in a first subsampler, taking a subsample of the incurrent fluid in a second subsampler, alternately providing excurrent fluid from the first subsampler to the first gas analyzer and to the second gas analyzer to measure the gas concentrations in the excurrent fluid, and alternately providing incurrent air from the second subsampler to the first gas analyzer and to the second gas analyzer to measure the gas concentrations in the incurrent fluid.

Abstract: A method for measuring the concentration of a component gas in a gas stream in the presence of water vapor comprises introducing a gas stream into a gas analyzer, measuring in the gas analyzer the concentration of the component gas and storing a value representing the measured concentration, measuring the water vapor pressure in the gas analyzer and storing a value representing the measured water vapor pressure; and measuring the total pressure of the gas stream and storing a value representing the measured total pressure of the gas stream.

Abstract: A telemetry base receives signals from at least one telemeter implanted in at least one animal. The base includes the following: a. a plurality of antennae to receive radiofrequency (RF) signals from the telemeter(s); b. a plurality of multiplexers connected to the antennae to increase the RF signal strength; c. at least one receiver circuit capable of processing RF signals from the antennae into electrical impulses; d. a central processing unit (CPU) to receive and process the electrical impulses into at least one parameter such as temperature; e. at least one digital address bus connected to the CPU and the multiplexer to select the antenna based on the best signal integrity of the antenna; f. a display to show the current parameters from the telemeters for analysis by the operator; and g. at least one analog-to-digital interface for receiving data from other external sensors.

Abstract: A gas-based regulatory apparatus has an electrical input, optionally connected to an analog to digital converter; a central processing unit (CPU) comprising a non-volatile memory for storing and retrieving program and configuration data and a random access memory for storing and retrieving other data; a visible alphanumeric display means connected thereto; a user input means adjacent to the display and connected to the processing means; an alarm driven directly or indirectly from the CPU; a pneumatic valve having an input port and an output port, and being driven directly or indirectly from the CPU; and a program that runs on the CPU, for receiving user input, measuring input voltages and pressure voltages from the analog to digital converter, displaying data, converting measured voltages to gas and pressure units, implementing a control algorithm, and driving the pneumatic valve and alarm.