Page 117 - Agriculture_Form_Three

Agriculture for Secondary Schools

Roughages
The term roughage is sometimes used interchangeably with forage. Roughages
include all feedstuffs of plant origin that contain high amount of fibre. Roughages
form the main part of feeds for cattle, goats and sheep. They are sourced from either
naturally growing plant materials such as natural grasses, legumes, tree leaves or
from pasture fields planted specifically for the purpose of feeding animals. It is also
common for livestock farmers to let the animal graze on the pastures, cut and feed
fresh forages or harvest and conserve natural and planted forages for use during dry
seasons. The forages harvested may be conserved in a dry form known as hay or
in a wet fermented form known as silage. In some cases, materials left behind after
harvesting cereal or pulse grains collectively known as crop residues are used as
feeds. The crop residues commonly used in Tanzania include stovers from maize
and sorghum, straw from paddy and wheat as well as bean haulms. Although these
feed materials are of low nutritional value, they still play an important role as feed
resources.

Concentrates
These include all feedstuffs that contain relatively low amount of fibre, high
concentration of specific nutrients (energy, protein and vitamins) and are easily
digestible. Concentrates are derived from plant and animal sources and form the main
part of feeds for pigs and poultry. In ruminants, they are often used as supplements.
Energy concentrates are derived from cereal grains including maize, wheat, rice and
sorghum grains and their milling by-products such as maize bran, rice polishing and
wheat pollard. Figures 5.9 (a) and (b) show some energy concentrates.

Figure 5.9 (a): Maize bran Figure 5.9 (b): Wheat bran

Protein concentrates are obtained from both plant and animal sources. Plant and
animal sources of protein are usually combined together during feed formulation.
This is done mainly for the purpose of balancing the amino acid composition in
the feed. It also helps to reduce the cost of the feed since animal sources are more

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AGRICULTURE FORM 3 9.11.2022.indd 106 10/01/2025 12:31