METHANE EMITTED BY RUMINANT LIVESTOCK CONTRIBUTES TO CLIMATE CHANGE AND REPRESENTS A CONSIDERABLE WASTE OF ENERGY. TO DEVISE MANAGEMENT PRACTICES TO MINIMIZE RUMINANT EMISSION OF METHANE AS WELL AS LOSS OF HEAT ENERGY, ACCURATE MEANS OF MEASUREMENT UNDER NORMAL PRODUCTION CONDITIONS ARE NECESSARY. DETERMINING THE MOST APPROPRIATE WAY OF USING A PORTABLE EQUIPMENT SYSTEM TO MEASURE METHANE EMISSION AND HEAT ENERGY PRODUCED BY GROUPS OF GOATS AND SHEEP IN PASTURES OR PENS WILL BE USEFUL IN FUTURE STUDIES ADDRESSING GREENHOUSE GAS PRODUCTION AND EFFICIENCY OF ENERGY USE. STUDIES WILL BE CONDUCTED TO DETERMINE THE MOST APPROPRIATE NUMBERS OF MEASURES DURING A DAY, DAYS OF ASSESSMENT, AND ANIMALS IN GROUPS IN PEN AND PASTURE SETTINGS WITH THE PORTABLE GROUP CALORIMETRY SYSTEM. IT IS EXPECTED THAT ACCURACY OF DETERMINATION WILL INCREASE WITH AN INCREASING FREQUENCY OF DETERMINATION AND NUMBER OF MEASUREMENT DAYS. THERE SHOULD BE A DIFFERENT OPTIMAL NUMBER OF ANIMALS IN GROUPS IN PEN AND PASTURE SETTINGS THAT YIELD ACCURATE MEASURES AND GREATEST NUMBERS OF OBSERVATIONS. THIS RESEARCH WILL FACILITATE USE OF MANAGEMENT PRACTICES THAT MINIMIZE GREENHOUSE GAS PRODUCTION AND IMPROVE EFFICIENCY OF NUTRIENT UTILIZATION BY SMALL RUMINANTS.