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COLLECTION: GOAT HANDBOOK
ORIGIN: United States
DATE INCLUDED: June 1992
Extension Goat Handbook
This material was contributed from
collections at the National Agricultural Library.
However, users should direct all inquires about the
contents to authors or originating agencies.
DOCN 000000024
NO C-3
GRASSES, FORBS AND BROWSE
J. E. Huston; Texas A&M U. Agr. Res. Ctr., San
Angelo
D. L. Ace; Pennsylvania State U., University Park
DE Nutrition
1 While much of the scientific agricultural community
attempts to provide more and better forages for specific
animal use, goats do well on what they have, provided
they are given the chance to choose. Although their
nutrient requirements exceed those of most other livestock
species, goats succeed while others fail. The reason
for this success is that goats are particular. They
consume the best parts only.
2 Vegetation Vegetation is often
divided into three groups: grasses, forbs, and browse
plants. Grasses are monocotyledons and belong to the
family, Gramineae. Leaves of these herbaceous plants
appear as blades, with parallel veins. Forbs, often
called weeds, are dicotyledons and include individual
plants from many families. Veins in the leaves are
not parallel but are netted or branched. The general
term, forb, refers to any herbaceous, broadleaf plant
without regard to family classification. Browse plants
include plants other than grasses and forbs but are
usually taller plants, such as trees, shrubs, and
vines having woody stems.
3 Nutritional Values of Grasses,
Forbs, and Browse Plants Even though grasses are usually
considered the most desirable type vegetation for
livestock production, forbs and browse plants often
contain higher levels of nutrients. Leguminous forbs
and browse, for example, commonly contain more than
25 percent crude protein, whereas perennial grasses
seldom exceed 15 percent in crude protein content.
The energy contents of flowers, fruits, seeds and
nuts of forbs and browse can exceed 1.6 megacalories
digestible energy per pound of dry matter. In grass
foliage, 1.2 megacalories per pound of dry matter
is considered high quality.
4 Each plant, whether a grass, forb,
or browse plant, is composed of many plant parts that
differ from one another in nutritional value. Generally,
leaves are more nutritious than stems and new leaves
more valuable than old leaves. There are some exceptions
to this generalization, especially when certain plant
chemicals, such as tannins prevent proper digestion
of the plant tissue. The total effect of these binding
chemicals on the nutritional values of plants are
not fully determined, especially in many of the browse
plants.
5 The Goat and Diet Selection Goats
are agile and have exaggerated control of their mouth
parts, allowing them to be very selective for diet.
They are able to stand on their hind legs and climb
rock cliffs and low growing trees to gain access to
relished plants and plant parts that are unavailable
to other livestock species. Goats have a mobile upper
lip, effective in nipping off plant parts very selectively.
As a result, the goat's diet is very diversified,
consisting of small components of a large number of
plant species. Very simplified vegetation, an all-grass
meadow, for example, does not provide good nutrition
for goats over a long period of time. Goats need access
to a wide variety of plants in order to exercise diet
selection, as different plants increase and decrease
in nutritional value with seasonal changes.
6 The Goat as a Brush Control Tool
Many of the browse species have invaded or become
overabundant in old, abandoned fields or on range
and pasturelands following prolonged grazing by other
livestock species. These invading species, collectively
called ''brush'', often can be suppressed or eradicated
using goats. Goats are effective as brush control
tools, when the following requirements are met:
1. The brush is either low-growing or is reduced to
low growth by mechanical means,
2. The brush species is preferred by goats,
3. Goats can be concentrated in large numbers for
a relatively short period, then removed for an extended
period.
7 Each time the goats are concentrated,
they consume the leaves and twigs of the brush species,
as well as a substantial portion of the grasses. When
the goats are removed, the grasses recover more quickly
than the brush. After several sequential grazing and
rest periods, the brush is reduced to a density easily
controllable, with a few goats included in the grazing
herd. This method of brush control has proven successful
in several regions of the United States, as well as
at many locations around the world.
GRASSES, FORBS AND BROWSE
COLLECTION;GOAT HANDBOOK
ORIGIN;United States
DATE_INCLUDED;June 1992
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