Mountain and moorland pony breeds when the colts and some of the fillies are removed for sale. The remaining fillies are usually branded to indicate ownership. Some geldings may also be turned out. Ponies still kept in this way include New Forest, Exmoor, Dartmoor and Welsh. Each of these breeds also has a population kept as fully domesticated animals. In horse shows mountain and moorland classes are divided into two subsections: small breeds and large breeds, although the four Welsh types are often shown in their own classes instead. They are overseen by the relevant breed society, and by the British Show Pony Society. Mountain
Animal genetic resources for food and agriculture sustainability of a breed and therefore to the potential for successful conservation activities." The Pantaneiro cattle of Brazil are only one example of many at risk of extinction. Despite the importance of animal genetic resources, their diversity has been continually decreasing over time. "Factors as causes of genetic erosion: One of the greatest threats to livestock diversity is pressure from large-scale commercial production systems to maintain only high-output breeds. Recent molecular studies have revealed that the diversity of today's indigenous livestock populations greatly exceeds that found in their commercial counterparts. Climate change and its impact on livestock is being studied.