Agriculture Reference
In-Depth Information
to their enclosure at night. Their wide beak contributes to feed wastage when fed con-
centrated feed rations. Their anatomy is similar to the chicken, except that the beak is
flattened, there is no comb or wattle, and there is webbing between the toes. The body
weight ranges from 1.4 kg (Mallard drake) up to 4.5 kg (Muscovy drake).
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Though
classed as a duck, the Muscovy breed is genetically related to geese. It prefers to
feed on grasses and roosts in trees in its native Amazon basin.
In most of the world ducks are raised for their meat and eggs. Ducks are the fastest
growing poultry animal, weighing 3 kg in only 6 to 7 weeks.
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They are generally less
prolific egg layers than chickens, producing up to 300 eggs per year under ideal con-
ditions. Under more common, free-ranging conditions, each duck will produce 40 to
60 eggs per year. An advantage of raising ducks for eggs is that they will lay their
eggs within 3 hours after sunrise and then forage for food. Chickens will lay eggs
for up to five hours after sunrise and only then start to forage for food. The most
common breed of duck is the Pekin. There are an unknown number of breeds,
mostly in Asia. They are classed as being for meat, eggs, herding ability, and other
characteristics important in a particular production system. Crosses between ducks
and the Muscovy are usually sterile (mule ducks) and are created specifically for
meat purposes. These crosses typically have a faster growth rate than chickens.
7.4.4 Geese
The two major domestic species of goose are descended from the wild Greylag goose
in Europe and the wild Swan goose of Asia.
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Both species interbreed and some com-
mercial breeds have resulted. A total of 96 breeds are recognized by FAO, though
there are certainly more. The Anser cygnoides breeds are distinguished by a knob at
the upper base of the beak. Most domesticated species are white. Brown pinfeathers
tend to discolor the skin when harvested, producing a dark speckled appearance.
Males (ganders) weigh from 2.8 kg (Philippine Domestic) to 12 kg (Shitou) when
mature. Eggs of most species weigh from 120 to 220 g each. Geese have gizzards
similar to chickens and ducks. The heavy muscles of the gizzard can grind more
fibrous materials than ducks or chickens and promotes digestion in the cecum. The
microbial fauna in the lower stomach also help to extract 15 to 30 percent of the
nutrition in many feeds.
The goose is able to utilize different food materials than chickens and ducks
because of its digestive system. Geese prefer grasses and grass seeds for feed. This
has led to their use as weeders in specific vegetable crops such as strawberries,
grapes, and onions. Geese feed on grasses and grass seeds, leaving most broadleaf
plants untouched.
7.4.5 Feeding Requirements
The care and feeding of most types of poultry fall within the mixed farming system of
animal production (Fig. 7.5). Within this system, poultry production can be classified as
free-range extensive, backyard extensive, or semiintensive. In Africa, Asia, and Latin
America, over 80 percent of the farms produce poultry using free-range or backyard
