Agriculture Reference
In-Depth Information
housing. These factors are temperature, air supply or
movement, and composition of air including ammonia,
carbon dioxide, humidity or other pollutants from animal
bedding, or from microbiological origin.
Animals continuously exchange heat with their environ-
ment. To maintain steady body core heat, homeotherms
(all animals that maintain their body temperature within a
predetermined range, including goats) gain heat from the
metabolic process through oxidation of proteins, fats, and
carbohydrates within the body. The rate of metabolism can
depend on size, feed intake, and levels of muscular activity
as well as the thermal environment. Animals can lose heat
either by radiation or non-evaporative heat transfer from
the body, or by evaporative heat transfer and respiration.
Non-evaporative heat loss is mainly in low temperatures
that can vary among animals depending on their coat or
skin thickness. The majority of evaporative heat loss
occurs at high temperatures, generally above 20-30°C
(68 - 86 ° F) (Mount, 1979 ). Optimum animal productivity
is achieved within the thermoneutral zone, when metabolic
heat production and energy expenditure are minimums (the
most effi cient condition in terms of productivity). However,
below the lower critical temperature (LCT), about 10°C
(50°F) for most animals, and above the upper critical tem-
perature (UCT), about 30°C (86°F) for most animals, they
lose energy to regulate body temperature. The LCT, UCT,
and the range of the thermoneutral zone are different
among species of animals and the environments that they
are in, including management practices. Skin thickness,
skin wetness, level of production, and type and level of
feeding may affect the animal's tolerance to extreme tem-
peratures. Dairy goats tend to be less affected by tempera-
tures below the LCT, compared with temperatures more
than the UCT. This is evident in their presence and
optimum performance in cooler regions of the world,
including the U.S. Larger ruminants having less surface
area to body mass are more temperature tolerant than
goats, but goats seem to adjust well to different thermal
zones. The ideal climatic conditions for a majority of
breeds of goats are the arid and semiarid climatic condi-
tions. In fact, according to the FAO, a majority of goats
are found in these regions of the world. However, goats
tend to be less tolerant to hot and humid climates as indi-
cated by their diminished survivability in hot and humid
regions of the world.
Ventilation or air exchange is also important for removal
of air pollutants, such as ammonia, in animal housing to
provide a stress-free environment. There are two venti-
lation requirements: one to prevent overheating and the
other for removing carbon dioxide, ammonia, dust, and
Table 17.3 Trough space requirements for
confi nement feeding, cm (inch).
Restricted
roughage
Ad libitum
roughage
Concentrate
Adult goat
50 (20)
25 (10)
15 (6)
>
60 kg BW
Growing kid
40 (16)
20 (8)
15 (6)
<
35 kg BW
Weaned kid
< 20 kg BW
30 (12)
15 (6)
10 (4)
Source: Adapted from ADAS, 1987 .
pastured, in temperate areas, at least 0.2 ha (0.5 ac) will be
required for one dairy goat. More pasture area is needed
in more marginal lands to avoid overgrazing.
The incidence of displacement and aggressive behavior
increased as the number of goats increased per feeding
space (Bøe et al., 2008), and low-ranked goats spent less
time feeding and more time queuing (waiting) than goats
in higher ranks. These results clearly state that for optimum
performance, goats should be provided with adequate
trough spaces for feeding to reduce aggression and thereby
allow for lower-ranked goats to have an opportunity to eat.
Table 17.3 provides a guideline for trough space require-
ments for goats based on size. Feeders should be reachable
for goats but high enough to avoid contamination with
fecal or urine matter.
ANIMAL REQUIREMENTS FOR HOUSING
There are a number of factors that can affect productive
effi ciency of animals that must be considered before decid-
ing if housing for goats is necessary. These factors include
climatic requirements, animal health, animal comfort, and
animal welfare (Whates and Charles, 1994). Technically
goats require a shelter that is windproof, draft proof, rain-
proof, and is free from condensation. Meeting the animal' s
requirements for climatic conditions, health, and comfort
can directly affect performance, whereas animal welfare is
a regulatory issue for farm animals in the U.S. and around
the world. Consumers are increasingly concerned about the
welfare of food animals and the conditions under which
their foods are produced. Providing a proper living envi-
ronment for food animals will improve productivity and
can be economical, if justifi ed.
Climatic Requirements
Climatic factors can infl uence animal productivity and
welfare and must be considered in relation to animal
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