AAP: AUSTRALIAN researchers will not fit plastic trousers to sheep as a means of measuring rear-end greenhouse gas emissions. But they will have to fit masks to thousands of sheep to see exactly what they are belching. Stung by climate adviser Ross Garnaut’s recent claim that sheep help cause climate change and people should eat kangaroo instead, the industry is responding with a large field trial. Sheep Cooperative Research Centre chief executive James Rowe said staff would …