Domestic duck

Domestic ducks are ducks that are raised for meat, eggs and down. Many ducks are also kept for show, as pets, or for their ornamental value. Almost all varieties of domestic duck apart from the Muscovy duck (Cairina moschata) are descended from the mallard (Anas platyrhynchos). Mallard ducks were first domesticated in Southeast Asia at least 4000 years ago, during the Neolithic Age, and were also farmed by the Romans in Europe, and the Malays in Asia. In ancient Egypt, ducks were captured in nets and then bred in captivity. During the Ming Dynasty, the Peking duck—mallards force-fed on grains, making them larger— was known to have good genetic characteristics.

Almost all varieties of domestic duck except the muscovy have been derived from the mallard. Domestication has greatly altered their characteristics. Domestic ducks are mostly polygamous, where wild mallards are monogamous. Domestic ducks have lost the mallard's territorial behaviour, and are less aggressive than mallards. Despite these differences, domestic ducks frequently mate with wild mallard, producing fully fertile hybrid offspring. Ducks have been farmed for thousands of years. In the Western world, they are not as popular as the chicken, because chickens have much more white lean meat and are easier to keep confined, making the total price much lower for chicken meat, whereas duck is comparatively expensive. While popular in haute cuisine, duck appears less frequently in the mass-market food industry and restaurants in the lower price range. However, ducks are more popular in China and there they are raised extensively.

Ducks are farmed for their meat, eggs, and down. A minority of ducks are also kept for foie gras production. The blood of ducks slaughtered for meat is also collected in some regions and is used as an ingredient in many cultures' dishes. Their eggs are blue-green to white, depending on the breed.

Ducks can be kept free range, in cages, in barns, or in batteries. Ducks enjoy access to swimming water, but do not require it to survive. They should be fed a grain and insect diet. It is a popular misconception that ducks should be fed bread; bread has limited nutritional value and can be deadly when fed to developing ducklings. Ducks should be monitored for avian influenza, as they are especially prone to infection with the dangerous H5N1 strain.

The females of many breeds of domestic ducks are unreliable at sitting their eggs and raising their young. Exceptions include the Rouen duck and especially the Muscovy duck. It has been a custom on farms for centuries to put duck eggs under broody hens for hatching; nowadays this role is often played by an incubator. However, young ducklings rely on their mothers for a supply of preen oil to make them waterproof; a chicken hen does not make as much preen oil as a female duck, and an incubator makes none. Once the duckling grows its own feathers, it produces preen oil from the sebaceous gland near the base of its tail. Domestic ducks can be kept as pets, in a garden or backyard, generally with a pond or deep water dish. If they are given access to a pond, they dabble in the mud, dredging out and eating wildlife and frog spawn, and swallow adult frogs and toads up to the size of the common frog Rana temporaria, as they have been bred to be much bigger than wild ducks, with a waterline length (base of neck to base of tail) of up to 1 foot (30 cm); the wild mallard's waterline length is about 6 inches (15 cm). Protection from predators such as foxes and hawks is required.