Sheep - AgRIS

sheep requires about 2 liters of water per day during winter and 3.5 to 4.0 liters during summer.
Sheep in desert areas can withstand water deprivation up to 3 days. Offering water on alternate
days has no deleterious effect. Sheep in desert areas with scanty and brachish water can tolerate
salt content up to 1 per cent in the drinking water.
ii) Energy
Energy is required for all vital functions like maintenance of blood pressure and muscle
tone, transmission of nerve impulses, ion transport across membranes, reabsorption in kidney,
protein and fat synthesis, secretion of milk and production of wool. Several variables viz. body
size, age, sex, level of growth and production activity and environmental conditions infiuence
energy requirement of animals. Energy deficiency for extended periods results in lowered
production of meat, milk and fibre. Deficiency of energy is manifested primarily as a lack of
growth, body tissue losses or reduced production. Energy is usually defined as capacity to do
work. Some of the terms that are used to express energy are ergs, joules, calories (cal), Kilo
calories (KCal), Mega calories (MCal) and therms. The gross energy, digestible energy,
metabolisable energy and net energy are usually expressed as cal, Kcal and Mcal per unit feed.
Other expressions of energy value of feeds include total digestible nutrients (TDN) and starch
equivalent (SE). In India TDN and ME (MCal/kg) are generally used to express energy value of
feeds. An adult non-pregnant sheep requires 93 KCal ME/KgW 0.75 , for maintenance. An
additional allowance of 50% over maintenance is generally provided to pregnant ewes. The
lactating ewes require still higher amount of energy: the maintenance requirement of lactating
ewes has been estimated as 102 KCal ME/KgW 0.75 .
Energy source in the body is met by feeding foods containing carbohydrats and fats.
Common carbohydrates sugar, starch, and cellulose or the fibrous or woody parts of plants.
They are characterized by the fact that in composition they contain hydrogen and oxygen in the
same proportion as these exist in water; they are free of nitrogen and therefore are often
referred to as the nitrogen-free extract offeeds. Grains are high in nitrogen-free extract while
roughages are much lower, and that in roughages is usually much less digestible, for in the
latter much of the material is in the form of fiber. Pentosans are similar in some respects to
starches and sugars but are found mainly in the fibrous portion of plants. The value of these
materials to sheep is oftwo distinct kinds: the fibrous portion helps to form bulk, a matter of
extreme importance in the diet of all herbivorous animals, of which sheep are a part; the sugars
and starches, are very important sources of energy. A surplus taken into the body may be
transformed into fat and stored as a reserve supply for later use in the production of heat and
energy. If the supply of carbohydrates is inadequate, it is possible for sheep and other animals
to make up for the deficiency by using the protein and fat contained inthe feed. Carbohydrates
are needed in abundance in the rations of fattening sheep. Apparently, these materials cannot be
used for body functions other than for the deposition of fat and the production of heat and
energy. One of the most common practical consequences of a lack of carbohydrates in the
ration is an increase in expense.
iii) Fat
Fat or similar materials are found to some extent in almost all feeds. Seeds of certain plants
are high in oils or fats, while the stems and leaves contain very little. From the standpoint ofthe
nutrition of sheep, it is likely that some fat in the feed is desirable, although it seems unlikely
that these animals suffer from a deficiency of dietary fat. Fat may be used for energy, or it may
be converted into body fat and stored with fat formed from other nutrients. Body fat of sheep
has a very high melting point, and it is apparently not affected in any significant way by the
kind or amount of fat in the usual feeds.
iv) Proteins
Proteins are very complex compounds which serve considerably different uses from those
served by the other nutrients. For sheep the proteins are almost exclusively of plant origin. The
leaves and seeds of plants are rich sources of proteins. The protein content of plants differs
greatly, both with respect to quantity and quality. Differences in quality seem to be closely
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