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6
Ducks
Domestic ducks (Anas platyrhynchos)' are well
known, but still have much unrealized promise for
subsistence-level production. Although a major re-
source of Asia, where there is approximately one duck
per 20 inhabitants, they are not so intensively used
elsewhere. On a worldwide basis, for instance, they
are of minor importance compared with chickens.
This is unfortunate because ducks are easy to keep, adapt readily
to a wide range of conditions (including small-farm culture), and require
little investment. They are also easily managed under village conditions,
particularly if a waterway is nearby, and appear to be more resistant
to diseases and more adept at foraging than chickens.
Moreover, the products from ducks are in constant demand. Some
breeds yield more eggs than the domestic chicken. And duck meat
always sells at premium. A few recently created breeds (notably some
in Taiwan) have much lower levels of fat than the traditional farm
duck. This development could open up vast new markets for duck
meat, especially in wealthy countries, where consumers are both
concerned over fat in their diet and eager for alternatives to chicken.
Ducks are also efficient at converting waste resources insects,
weeds, aquatic plants, and fallen seeds, for instance-into meat and
eggs. Indeed, they are among the most efficient of all food producers.
Raised in confinement, ducks can convert 2.~2.6 kg of concentrated
feed into 1 kg of weight gain. The only domestic animal that has better
feed conversion is the broiler chicken.
Raised as village birds and allowed to forage for themselves, ducks
become less productive but become even more cost effective because
much of the food they scavenge has no monetary value.
' This is the commonly used scientific name; others are also used, however. The muscovy
duck is covered in a later chapter.
91
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Tsaiya ducks, Taiwan. (Food & Fertilizer Technology Centre)
AREA OF POTENTIAL USE
Worldwide.
APPEARANCE AND SIZE
MICROLIVESTOCK
Several distinctive types have been developed in various regions.
Most have lost the ability to fly any distance, but they retain a
characteristic boatlike posture and a labored, waddling walk. The
Indian Runner, however, has an almost erect stance that permits it to
walk and run with apparent ease.
Domestic ducks range in body size from the diminutive Call, weighing
less than I kg, to the largest meat strains (Pekin, Rouen, and Aylesbury,
for example) weighing as much as 4.5 kg. For intensive conditions,
the Pekin is the most popular meat breed around the world. In
OCR for page 93
DUCKS
93
confinement it grows rapidly weighing 2.5-3 kg at a market age of 7-
8 weeks. In addition, it is hardy, does not fly, lays well, and produces
good quality (but somewhat fatty) meat.
The Khaki Campbell breed is an outstanding egg producer, some
individuals laying more than 300 eggs per bird per year.
The Taiwan Tsaiya (layer duck) is also a particularly efficient breed.
It weighs 1.2 kg at maturity, starts laying at 12~140 days, and can
produce 26() 290 eggs a year. Its small body size, large egg weight,
and phenomenal egg production make Brown Tsaiya the main breed
for egg consumption in Taiwan. More than 2.5 million Brown Tsaiya
ducks are raised annually for egg production.2
DISTRIBUTION
The domestic duck is distributed throughout the world; however
its greatest economic importance is in Southeast Asia, particularly in
the wetland-rice areas. For example, about 28 percent of Taiwan's
poultry are ducks. In parts of Asia, some domestic flocks have as
many as 20,000 birds. One farm near Kuala Lumpur, Malaysia, rears
40,000 ducks.
STATUS
Although ducks are abundant, some Western breeds are becoming
rare. Indigenous types are little known outside their home countries
and have received little study, so their status is uncertain.
HABITAT AND ENVIRONMENT
These adaptable creatures thrive in hot, humid climates. However,
during torrid weather they must have access to shade, drinking water,
and bathing water.
Ducks are well adapted to rivers, canals, lakes, ponds, marshes,
and other aquatic locations. Moreover, they can be raised successfully
in estuarine areas. Most ocean bays and inlets teem with plant and
animal life that ducks relish, but (unlike wild sea ducks) domestic
breeds have a low physiological tolerance for salt and must be supplied
with fresh drinking water.
2 Information from Cha Tak Yimp and Chein Tail
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94
BIOLOGY
MICROLIVESTOCK
Ducks search for food underwater, sieve organic matter from mud,
root out morsels underground, and sometimes catch insects in the air.
Their natural diet is normally about 90 percent vegetable matter (seeds,
berries, fruits, nuts, bulbs, roots, succulent leaves, and grasses) and
10 percent animal matter (insects, snails, slugs, leeches, worms, eels,
crustacea, and an occasional small fish or tadpole). They have little
ability to utilize dietary fiber. Although they eat considerable quantities
of tender grass, they are not true grazers (like geese), and don't eat
coarse grasses and weeds at all. Sand and gravel is swallowed to serve
as "grindstones" in the gizzard.
When protected from accidents and predation, ducks live a surpris-
ingly long time. It is not unusual for one to continue reproducing for
up to 8 years, and there are reports of exceptional birds living more
than 20 years.
Despite large differences in size, color, and appearance, all domestic
breeds interbreed freely. Eggs normally take 28 days to incubate;
brooding and rearing is performed solely by the female.
Depending on breed, a female may reach sexual maturity at about
20 weeks of age. Most begin laying at 2~26 weeks, but the best egg-
laying varieties come into production at 1~18 weeks and lay profitably
for 2 years.
BEHAVIOR
It is generally well known that ducks are shy, nervous, and seldom
aggressive towards each other or humans. Skilled and enthusiastic
swimmers from the day they hatch, they spend many hours each day
bathing and frolicking in any available water. However, most breeds
can be raised successfully without swimming water.
Although wild ducks normally pair off, domestic drakes will mate
indiscriminately with any females in a flock. In intensively raised
flocks, 1 male to 6 females, and in village flocks, 1 male for up to 25
females, results in good fertility.
Most domestic ducks, particularly the egg-laying strains, have little
instinct to brood. If not confined, they will lay eggs wherever they
happen to be-occasionally even while swimming. To facilitate egg
collection, some keepers confine ducks until noon.
Opposite: Duck farm in China. Although ducks are naturally cautious, they quickly
become accustomed to familiar humans. (R.N. Matheny, The Christian Science Monitor)
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96
MICROLIVESTOCK
Hi_
o of;
'it At\
Native distribution of the mallard, ancestor of the domestic duck. The Rouen a major
commercial duck of France is almost identical in coloration to the wild mallard. From
such birds with their iridescent green heads, brown necks, and gray and green bodies-
white mutants were selected in medieval times. Today's big white breeds developed in
this way.
USES
As a meat source, ducks have major advantages. Their growth rate
is phenomenal during the first few weeks. (Acceptable market weights
can be attained under intensive management with birds as young as
~7 weeks of age.) Yet, even in older birds, the meat remains tender
and palatable.
Eggs from many breeds are typically 2~35 percent larger than
chicken eggs, weighing on average about 73 g. They are nutritious,
have more fat and protein, and contain less water than hen's eggs.
They are often used in cooking and make excellent custards and ice
cream. Eggs incubated until just before the embryos form feathers
produce a delicacy known as balls in the Philippines. Salted eggs are
popular in China and Southeast Asia.
Feathers and down (an insulating undercoat of fine, fluffy feathers)
are valuable by-products. Down is particularly sought as a filler for
pillows, comforters, and winter clothing.
Ducks have a special fondness for mosquito and beetle larvae,
grasshoppers, snails, slugs, and crustaceans, and therefore are effective
pest control agents. China, in particular, uses ducks to reduce pests
in rice fields.3 Its farmers also keep ducks to clear fields of scattered
grain, to clear rice paddy banks of burrowing crabs, and to clear
aquatic weeds and algae out of small lakes, ponds, and canals. This
3 Ducklings, at hatching, are readily "imprinted." Farmers in Asia wave a white flag
on the end of a bamboo pole over the ducks as they hatch. The ducks then think that
the flag is their mother and follow it to the rice paddy, stay around it all day, and follow
it back to the sheller in the evening.
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DUCKS
97
not only improves the conditions for aquaculture and agriculture, it
also fattens the ducks.
HUSBANDRY
In Southeast Asia, droving is a traditional form of duck husbandry,
much as it was in medieval Europe. The birds are herded along slowly,
foraging in fields or riverbanks as they march to market. The journey
might cover hundreds of kilometers and take as long as six months.
This process, however, is generally declining, and most ducks are
raised under farm conditions where they scavenge for much of their
feed. Throughout Southeast Asia, ducks have been integrated with
aquaculture.
Ducks can be raised on almost any kitchen wastes: vegetable
trimmings, table scraps, garden leftovers, canning refuse, stale produce,
and stale (but not moldy) baked goods. However, for top yields and
quickest growth, protein-rich feeds are the key. Commercial duck
farms rely on such things as fish scraps, grains, soybean meal, or
coconut cake. Agricultural wastes such as saga chips, palm-kernel
cake, and palm-oil sludge are being used in Malaysia.4
Ducks have a very high requirement for niacin (a B vitamin). If
chicken rations are used, a plentiful supply of fresh greens must be
provided to avoid "cowboy legs," a symptom of niacin deficiency.
ADVANTAGES
Of all domestic animals, ducks are among the most versatile and
useful and have multiple advantages, including:
· Withstanding poor conditions;
· Producing food efficiently;
· Utilizing foodstuffs that normally go unharvested;
· Helping to control pests; and
· Helping to fertilize the soil.
Also, they are readily herded (for instance, by children).
Excellent foragers, they usually can find all their own food, getting
by on only a minimum of supplements, if any. Raising them requires
little work, and they provide farmers with food or an income from the
sale of eggs, meat, and down.
Ducks can grow faster than broiler chickens if they have adequate
nutrients. Like guinea fowl and geese, they are relatively resistant to
4 Information from Yeong Shue Woh.
OCR for page 98
nom~=l~o ~ neck
Maw species of duck adapt Idly ~ Opted it is sure
phsln~ therefore that only the mallard and the muscat hoe
been domesOmted so far. Seems gild ~opl~1 specks seem
especla~y worth ~lorlng far possible mare use in Third
world Ins. Bemuse of the ~r-round propel math, their
lnsOnct to mlgmte is either absent or unpronounced, and the
ha Lear of fat (a -~m of tempe~te~cllmate duck that
consumers in many counseled consider a drawback) ~ Icing.
Moreover bemuse of unlay d~ngt~ they are ready to
baa ~ am Ome of me ma. Incas far dome
as ~oplml duck include:
~ ~lstllog duck (Deb species). These large col-
or~l, goosell~ birds are noted far their b~utl~l, cheerful
whlsue. ~ They are long~nec~d perching duck that are Fund
throughout me tropics. ~ and large they are gregarious
Seder verger and less arboreal than the muscle
an poorly -1~ far a poultry specks.
The black-beHled mating duck (D. aufu~af~) seems
especiaUy promising. it ~ common throughout tropical Iberia
~out~stern Unked Sates to northwestern ~genUna) and ~
sometimes Rapt in semlmpt~. Ocm~onaU~ in the highlands
of Guatemala far lus~nc~ lindens sea mung ones they hoe
read as pea. men hand reared me beds In become very
amp ~ ~ They eat In and other vege~tlon, require no
mmlng Item and ~11 ~lun~rlly use nest baas. in the
~1~ they 'puma' large numbers of egged so that men
subs~nUal numbers ~= remand far adl~cial hatchln~ the
pul~lons shad Nat be arced.
~ Armor mod duck Iffy typecast The muscat (C.
m~~) Is domesUmted by South Sweden loans long
before Europeans aimed gee page 124t as counters
the Fresh of Southpaw gala and troplml Calm ark howdy
unwed as domesHm~s. The ~l~-~n~d mod duck (C.
s~~) is Fund Tom astern lads to Jam. Madlaub~ duck
(C. ~-f) occurs in Fresh and boded Hannah Tom
Slew Leone to Zaire. Both are are in mpUvl~ but might wed
prove to be future Propel resources. Both are Dotingly similar
to musc~les in size and health being large phle~atl~
Seder and omnivorous.
* Thea are an_ as "page' in Spanis~om the ~ pretty "pee-hee-hee~ sound
they maw.
* ~ in the lg50~ pant Moorer Wilson Pence kept some at his home ~ Antigua
Ouatem~a. at d_ each morning one would enter his bedroom and tug on
the blankets anus he got up and threw ~ into the patio ~un~ln.
I One census of nest boxes in Mexico showed that out of22,000 eggs ~ SO
percent were not hatched.
98
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DUCKS
99
disease. They also have a good tolerance to cold and, in most climates,
don't need artificial heat.
LIMITATIONS
Predators are the most important cause of losses in farm flocks.
Ducks are almost incapable of defending themselves, and losses from
dogs and poachers can be high. Locking them in at night both protects
the birds and prevents eggs from being wastefully laid outside.
Ducks do suffer from some diseases, mainly those traceable to
mismanagement such as poor diet, stagnant drinking water, moldy
feed or bedding, or overcrowded and filthy conditions. Of all poultry,
they are the most sensitive to aflatoxin, which usually comes from
eating moldy feed. They are also susceptible to cholera (pasteurellosis)
and botulism, either of which may wipe out entire flocks. Duck virus
enteritis (duck plague) and duck virus hepatitis also can cause severe
losses.
If not carefully managed, ducks can become pests to some crops,
especially cereals.
As noted, ducks tend to be extremely poor mothers and can be
helped by using broody chicken hens or female muscovies as surrogate
mothers.
Major limitations to large-scale, intensive production are mud, smell,
and noise.
Defeathering ducks is much more difficult than defeathering chickens
because of an abundance of small pinfeathers and down feathers.
RESEARCH AND CONSERVATION NEEDS
These birds already function so well that no fundamental research
needs to be done. Nonetheless, there are a number of topics that could
improve their production.
For example, different types of low-cost systems need to be explored
and developed. These must be low-input systems since cash is a
limiting factor for most subsistence farmers. One possibility is the
integration of duck and fish farming.
A survey of all breeds is needed to determine their status and
likelihood of extinction.
One need in countries that already have ducks is to encourage the
consumption of duck meat. Indonesia, for instance, has 25 million egg-
producing ducks, but little duck meat is consumed.
Research on economically significant diseases is needed.
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Brown Chinese Geese
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Representative terms from entire chapter:
duck meat
