The disease risk involved in the association of different groups of cattle on a commonage is not dissimilar to the situation arising in marts where animals are gathered together on a regular basis. Provided animals are of the same health status entering the commonage, there is no undue risk to the overall group.
Eligible animals, females and bulls over 12 months of age, must, by law, be tested for brucellosis within 30 days of moving to a commonage and again within 30 days of returning to the main herd. If suitable testing facilities are not available on the commonage the animals should be isolated in the main farm on return and tested before mixing with other cattle in the herd. It is strongly recommended, also, that all animals grazed on commonages are TB tested before they return to the main farm.
To qualify for a herd number in the first instance each herdowner is required to have holding and handling facilities for their animals. There are no specific holding facilities required on commonages.