Animal husbandry in the British Agricultural Revolution of the 18th century, when livestock breeds like the Dishley Longhorn cattle and Lincoln Longwool sheep were rapidly improved by agriculturalists such as Robert Bakewell to yield more meat, milk, and wool. A wide range of other species such as horse, water buffalo, llama, rabbit and guinea pig are used as livestock in some parts of the world. Insect farming, as well as aquaculture of fish, molluscs, and crustaceans, is widespread. Modern animal husbandry relies on production systems adapted to the type of land available. Subsistence farming is being superseded by intensive animal farming in
Mountain and moorland pony breeds graze freely on lush forage may develop related health problems, including laminitis. The various types range from about to over . Shetlands are smaller, not to exceed . Shetlands are measured in inches. Some breeds, such as the Exmoor, are uniform in colour and pattern, but others permit a wide range of colours. However, the Shetland is the only M&M breed that can be skewbald or piebald, though even Shetlands cannot be "spotted." Several types of mountain and moorland ponies still live in a semi-feral state on unenclosed moorland or heathland. These areas are usually unfenced common land, on which