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close this book Animal traction
close this folder Appendix B: Animal nutrition
View the document Energy needs: bovine animals
View the document Energy needs: equine animals
View the document Nutrient needs of draft animals: protein, minerals, vitamins
View the document Feeds and feed composition
View the document Calculating a ration
View the document Recommended rations and feeding practices

Appendix B: Animal nutrition

Several systems have been devised which make it possible to express the nutritional requirements of work animals and formulate diets based on corresponding nutrient and energy values of feeds. A simple and practical method used in many parts of Africa is based on a standard called the forage unit. A forage unit is defined as the net energy value of one kilogram of barley. It is the energy contained in the proteins, carbohydrates (starches), and fats which compose the barley and which the animal does not lose through elimination of feces, urine or gas, or in heat (work) produced by digestive organs. Net energy is defined as the energy available for maintenance of body functions-heartbeat, respiration, heat, motion. Energy intake above maintenance level is stored as fat or used for production or work. The abbreviation U.F. (Unite Fourragère) designates one (1) forage unit.


Energy needs: bovine animals

Oxen are ruminant. This means that they swallow large amounts of unchewed food as they graze and eat. Later, they regurgitate this feed in small portions (boluses) and chews it thoroughly. The micro-organisms (bacteria and protozoa) in the animal's forestomach (rumen) break down fibrous feeds (including the cellulose) and use them as a substance for growth. These micro-organisms and their products then become digestible nutrients for the animal. For this reason, ruminants can derive many nutrients from roughage whereas other animals cannot.

Deficiencies in energy, protein, phosphorous and Vitamin A are likely to occur in animals grazing forage on arid land. If the land has very poor forage, the animals may use up more energy obtaining feed than they can get from feed. This creates a net loss of energy to the animal. An energy supplement must be given daily to the animal, but protein, phosphorus and Vitamin A supplements may be effective if provided only once a week. Daily hand feeding of a supplement is the best method for updating the amount consumed.

The following energy requirements for ruminant draft animals have been established at agricultural research centers in Africa:

Bovine Animals

• The maintenance energy requirement-the amount of feed energy needed to keep a non-working animal from gaining or losing weight-is represented as "E". Tests show that a 300-kg idle bull needs the equivalent of the energy contained in 2.6 kg of dry barley grain-or 2.6 U.F.-to sustain its weight. The bull's maintenance requirement is expressed as E 3 2.6 U.F. (CEEMAT, Manuel de Culture avec Traction Animale, 1971).

• The size of the animal affects its maintenance requirement:

Daily maintenance requirements of oxen (idle).

(Taken from two tests; figures are approximate values.)

Weight of Animal Kg

Maintenance Requirement ("E") U.F.



















• The total daily energy requirement is the sum of the maintenance ration-the food energy needed to keep-a-nonworking animal from gaining or losing weight-and a quantity which can be called the work ration. CEEMAT suggests that for an oxen doing light work, the total energy required is "E" (maintenance) + 1/2 E. This can be easily expressed as T = 3/2 E. CEEMAT further suggests for oxen doing medium work T = 2 E, and for heavy work T = 5/2 E. Using this information in conjunction with tables which give the energy values of various feeds, the farmer and/or extension person can formulate or "compound" a ration of roughages and concentrates which can be expressed as a specific number of forage units. For example, if a 300-kg ox is going to be used for plowing (heavy work), it needs about 6.5 U.F. (T = 5/2 E; or T = 2.6 x 5/2 = 6.5) to maintain its weight Later in the season, when lighter weeding and cultivating operations are performed, the diet would be reduced to about 5 forage units (2.6 x 2). If the animal were used for occasional cart work, as might be the case during harvest operations, or if it were being trained, the energy requirement would range between 3 and 4 units (light work).


Energy needs: equine animals

Horses, donkeys, and mules are non-ruminant animals. They do not store food and later chew it, as oxen do. In addition to their molars, they have a set of upper and lower front teeth suitable for grinding roughages. (Bovines have no upper front teeth: they pull the grass loose, swallow it, and later bring it up and chew it with their rear molars.) With equines, digestion begins in the mouth, continues in the stomach, and is completed by various intestinal organs.

Equine animals must be fed with respect to their particular digestive functions and abilities. Where an ox can be fed its entire ration at the end of the day, a working horse, because of its smaller stomach and faster rate of metabolism, should be given its feed in small quantities. This facilitates complete, regular digestion of nutrients and ensures that the animal will be comfortable when working. A common plan is to feed the grain (concentrate) ration in three equal parts, morning, noon, and night; the roughage ration 1/2-3/4 at night, the remainder being given in the morning and at noon.

Body weight being equal, horses have somewhat higher maintenance energy needs than oxen because they are naturally more active. Their activity is related to their more nervous disposition and higher rate of metabolism (rate of using digested nutrients to build and repair body tissue and to produce heat and work). But horses can store more energy in their muscles than oxen and this explains their ability to produce greater bursts of power and work at a faster rate.

Research in both tropical and temperate climates shows that equine animals need about twice their maintenance requirements when doing medium-to-hard work. The following guidelines are suggested by CEEMAT for equines:

Idle horses: 2.5 U.F. per day (Assume 250-kg horse.)

Working horse: 5.0 U.F. per day (Assume 4-5 furs. pulling cultivator, medium soil.)

Idle donkey: 1.5 U.F. per day (Assume 100-kg donkey.)

Light work donkey: 2.5 U.F. per day (Assume 3 hrs., cultivator, light soil.)

Continuous work donkey: 4.0 U.F. per day (Assume 5 hrs., cultivator, light-medium soil.)

Unfortunately, very little data is available on the value of feeds as they apply to equine animals in the tropics. Thus it is necessary to use the tables adapted for bovines when formulating diets. Experience indicates that the values are generally applicable with the exception of straws. Bacteria in the ruminant's stomach enables it to digest straw and low-grade roughages effectively. Equines can derive very little energy from coarse fiber, so care must be taken to supply them with better hays and fodders.


Nutrient needs of draft animals: protein, minerals, vitamins

It can be assumed, generally, that a ration formulated from high quality pasture grasses and grains will supply, in addition to an animal's energy needs, the proteins, vitamins, and minerals necessary for overall health. However, imbalances can result from seasonal unavailability of feeds or conditions which affect the quality of feed. As pasture grows older, for example, the minerals tend to move from the leaves and stems downward into the roots where the grazing animal does not get them; or, if soils are low in phosphorus (as is often the case on tropical range), the grass which derives its nutrients from the soil also will be low in phosphorus. Such considerations make it advantageous for the stockowner to have some knowledge of the classes of feeds and their nutritional composition.

The protein and mineral needs of draft animals are summarized in the table below. While nutrition lists have shown that these needswith the exception of salt, which is lost in sweat-do not increase as the animal performs more work, serious problems can result from deficiencies. Without protein, the body cannot renew cells that form muscles and other tissues. Minerals are important in the growth and maintenance of skeletal structure as well as in metabolic and digestive function. Calcium and phosphorous values are given in most feed composition tables; if they are absent in natural feeds, they must be given as an additive in the concentrate mix (grains or meal) or in a block lick with salt.

A standard mineral supplement is made of two parts calcium, one part phosphorus and one part salt. Bone meal is prepared by boiling or steaming fresh bones and then pulverizing and drying them. This feed contains about 20% calcium and 10% phosphorus, a good ratio of these important minerals.


Requirements may be adjusted depending on the elements available in the pasture where the animal grazes. A mineral-starved animal should not be given free access to a lick or loose mixture. Instead, mix the correct does in with its concentrate.

A ration is a combination of feeds which provides the daily requirements for energy, protein, vitamins and minerals. Since the chemical composition or nutritional value of grain or pasture is determined by soil, weather, and other environmental factors, rations should be formulated using data obtained from regional testing centers. When this is not possible, other tables may be used, but with attention to the system of measuring as well as basic principles of feeding.


Feeds and feed composition

The feed given to draft animals is called forage. Forage sometimes refers to the leafy, fibrous, or tuberous portion of plants consumed by animals, but it may also refer to any edible portion of the plant. Forage may be wild or domestic, fresh or dry, standing (as in the field or forest) or harvested and stored. When green forage is fermented in a pit or silo, it is called silage.

It is important to distinguish the various types of forage materials, know their basic nutritive properties, and understand how they are analyzed before using feed composition tables. (Feed Composition Tables)

Forages are divided into roughages and concentrates. Roughages include green pasture (pasture grass), hays, legumes, and fadders. They are classified together because of the fiber content. When a feed analysis is made on roughages, all of the moisture is removed and composition is given on a "100% dry matter basis". That is, only the plant solids are analyzed.

Concentrates include low fiber, highly digestible feeds like grain, grain by-products, and high protein meals. They are analyzed on an "asfed basis", which means the feed is analyzed as it is normally fed to the animal.


Pasture refers to any grass or legumes, usually green, which are fed to animals. Pasture may also refer to the land area where the plants grow and where the animals graze. Pasture is highest in nutritional value when it is young and succulent (high in moisture).

Green Chop or Soiling Crop

Normally, work animals are allowed to graze. At times, however, plants are cut and brought to

them. Cut pasture is called green chop or soiling crop. The rainy season work schedule may limit daytime grazing and the farmer may want to feed fresh-cut pasture in the stable or paddock area rather than send animals out at night.

A maturing pasture loses moisture. Feed composition tables reflect water loss by the increasing percentage of dry matter and decreasing amounts of digestible protein, minerals, and digestible energy (forage value). Most grasses with a dry matter content between 20 and 30% have greater than maintenance nutrient content. Grass with a dry matter range of 20-40% is sometimes classified as "standing hay".


Hay is any grass or legume which is cut (or mown), dried, and preserved as a winter or dry season forage. The dry matter content of hay ranges from 40-85%. Hay has a high nutrient quality when it is cut before it goes to seed. Cut grass is allowed to dry, or "cure," in the field. Because the grass contains moisture, it must be turned to expose the underside to sunlight; otherwise, it will mold. The hay is cured when it snaps without releasing juice or moisture (this usually takes 1-3 days in the tropics). Hay is stored in an enclosed compartment (an old house or hut is suitable if not termite infested) where light and wind cannot enter and cause further drying. In the humid tropics where molding is highly likely, air circulation (wind) is an advantage, and storage should allow for this. If late season rains make it difficult to cure hay, grass can be preserved by making it into silage (see below).

Good quality hay is green in color, slightly brittle, has a clean, fragrant smell, and is free of dirt, stones, and woody stems. If hay is offered from a rack or trough, it does not pick up dust; dusty hay should be sprinkled with water before it is fed to keep animals from developing heaves (coughing condition) which can lead to pneumonia.

Most kinds of grass hay (except legume hay) of the same quality or grade have about equal nutritional value. The definition of "hay" varies. Some tables, especially those based on arid area


% dry matter

% digestible protein*

digestible energy (U.F.)

Green pasture

under 20

over 6

over 0.6

Standing hay




Cured hay




Grass straw


under 1

under 0.4

*Values based on 100% dry matter.


Straw is dead or dying grass. It contains very little moisture, is high in coarse fiber and low in nutritional value. Bovine animals, because of unique digestive abilities, are able to derive more nutrients from the fibers than horses or donkeys. Straw is especially useful when animals are kept on lowenergy diets (during the off season); then it should be fed with protein and mineral supplements. Straw contains few vitamins; these are supplied in the high quality hays and silages which should comprise the greater part of the roughage diet.


Legumes include nitrogenfixing plants like clover, alfalfa or beans which are much higher in protein, calcium, and Vitamin A and D content than grasses. Legumes can be offered fresh, as silage or as hay. Their ability to "fix" or put nitrogen into the soil makes them an important part of crop rotation schemes. Planted in association with grass crops, legumes improve both the soil and the crop, adding fertilizer (nitrogen) to the pasture mix. The leaves (and stems) of cowpeas, soybeans and peanuts can be dried as hay or wilted and preserved as silage after the seed is harvested. These feeds, when mixed with drier, coarser forages, improve the nutritional value of the ration, and also have a mild laxative effect that helps the animal eliminate the indigestible fibers. However, fast-growing lush young legumes in the pre-flowering stages may cause bloat or colic when offered to cattle or equine animals, and therefore should be avoided or restricted.


Fodder is the combination of leaves, stems, husks, hulls (peanut shells), cobs, or grain which is chopped, mixed, and usually fed in a dry state. Corn (or sorghum) grown specifically for animal feed and cut before the grain matures is called corn fodder. Corn fodder may be cured, ensiled, or fed fresh. Shock corn is similar to fodder but the grain has been allowed to mature before the plant is cut and chopped. Corn stover is a mixture made of dried stalks, leaves, and husks; the ear (cob and grain) has been removed. Tree fodder is a term applied to the leafy tree branches which graziers (herders) cut for their animals. In Africa, many species of Acacia are used as tree fodder. The leaves and stems are green during the dry season; they are high in calcium and phosphorous.


Grain is the seed portion of cereal plants-corn, sorghum, millet, and rice. Grains are low in the bulky fibers that constitute the plants which produce them; as a result, they are classified as "concentrates". They are high in starch value (carbohydrates) and therefore an important source of energy to work animals that have limited time to graze. They are not low in protein, but the proteins found in grain are not as easily digested as those found in legumes. Animals not accustomed to eating grain may find it unpalatable; in these cases the grain should be partially crushed and a small quantity of salt or brewers' wet meal added (see below). The feeding of shock corn or fodder/grain mixes is an effective means of introducing grain into the diets of animals raised on pasture. Some tests made in West Africa approximate the total nutritional value of grains as compared to quantities of mixed natural pasture:

1 kg of crushed millet = 7 kg of pasture

1 kg of crushed corn = 9 kg of pasture

1 kg of cotton seed = 6 kg of pasture.

Some grains have a U.F. value greater than one (1) because of high fat content. Fat has 2.25 times more energy per unit than carbohydrates.

Overfeeding of grains results in serious digestive problems. Generally speaking, an animal should not be fed more than 2 kg of grain per day. Horses may "bolt" grain by swallowing it whole or only partially chewed. This can be prevented by mixing grasses or legumes in with the grain or by placing several large, round stones in the feed.

Grain By-products

These include the hulls, brans, polishings and germs (centers) of the grain kernel. They are separated from the meaty, starchy portion of the kernel during the milling process. The hull is the hard, outer shell of the seed. Softer layers called bran may be found between the hull and the meat, or in the outermost coating (wheat has no hull but rather bran layers). Polishings are powdery residues that are separated from the finer flour when rice grain is milled. Brewers' wet meal is the residue of sprouted millet, corn or sorghum which is boiled to make beer. In Africa brewers' meal is sometimes mixed with water and offered as a mash to horses. Grain by-products (except for hulls) are generally high in fiber, protein and minerals and are less expensive to feed than whole kernels.

Seeds and Seed Cake

The seeds and seed cake of cotton plants (oil seed) and bean, pea, and peanut plants (legume seed) are high in energy and fat and may be fed whole or in a processed form. When the hulls (shells) of peanuts or cotton are removed and the oil extracted from the raw meat, the or cake. Sometimes the meal contains some hull material; it almost always contains some oil. Meal and cake have the same composition, but meal is loose and finely ground whereas cake consists of large chunks.


Silage is succulent forage material which has been cut, chopped and preserved in an air-tight compartment. It is a palatable, inexpensive feed which is higher in moisture and nutrient content than either hay or dry fodder. It is extremely useful in areas where seasonal dryness limits natural grazing. Green forage, preferably corn or sorghum fodder, young grass, and legumes are wilted in the field to a moisture level of 60-70X. This takes from 2 to 24 hours depending upon the humidity. The forage is dropped when stems can be twisted without breaking, but before leaves show any signs of dryness. The chopped plants then are layered and compacted in a 2mx2mx2m earth walled pit (or longer trench of equal depth, slightly pitched to allow for drainage). The pit is covered with earth and a natural fermentation process occurs. If the plant material has been tightly compressed without air pockets or leaks, no molding or rotting should occur. Hay, dry fodder, or partially-wilted legume tops (such as the leaves of the harvested peanut plant) also may be ensiled, but in drier regions, some water may have to be sprinkled in with the forage as it is trampled down to ensure that fermentation occurs. (For further information on silage, see ICE Reprint No. lie, Utilization and Construction of Pit Silos.)


Calculating a ration

Ration calculation can be demonstrated by the following examples using Table A (see page 188).

Example 1. To calculate the amount of Sudan Grass #1 needed to meet the U.F. maintenance requirement of a 300-kg bull. The value in Table A for digestible protein, phosphorous, calcium and U.F. are based on 100% dry matter. However, one kg of fresh roughage has less than 100% dry matter. Therefore, the first step is to adjust the amount of dry matter per kg of fresh roughage to 100% dry matter. For Sudan Grass #1, the percentage of dry matter per kg is 29.7%. One kg of fresh Sudan Grass #1 is adjusted to a 100% dry matter basis by the following calculation:

1/29.7% = 3.36 kg (100% dry matter basis)

This means that 3.36 kg of fresh Sudan Grass #1 contains one kg of dry matter. Step two is to locate the U.F. maintenance requirement of a 300-kg bull. The daily maintenance requirements of oxen chart shows the U.F. value of a 300-kg bull as 2.6. Step three is to calculate the amount of fresh Sudan Grass #1 needed for a 2.6 U.F. value. If 3.36 kg of fresh Sudan Grass #1 yields 0.57 U.F., then the needed calculation is:

3.36 x 2.6/0,57 = 13.3 kg.



Therefore, the bull requires 13.3 kg of green Sudan Grass #1 per day.

Example 2. To calculate the amount of Sudan cured hay to meet the U.F. maintenance requirement of a 300 kg bull, follow the same steps:

Step 1)

100/93.2 = 1.07

Step 2)

1.07 x 2.6/0.41 = 6.78 kg (U.F. value 1 kg dry matter)

Therefore the bull requires 6.78 kg of hay to meet its maintenance requirements. Calculation of protein and mineral contents of Sudan grass indicates that the fresh material meets nearly all of the animals' needs, but that the hay is deficient in every category. During the dry season, then, the stockowner would give the bull a grain supplement or mix a legume hay (high nutrient value) with the Sudan hay in order to balance the ration.

Feeds presented on an "as-fed" basis do not need adjustment for dry matter content.

To formulate a ration for a 300-kg bull:

1) Determine the animal's weight. Here, the weight is given as 300 kg.

2) Determine the maintenance requirements (per day basis).

U.F. (forage units) = 2.6 for a 300-kg bull

D.P. (digestible protein, or, in some charts "M.A.D." -- matière azoté digestible) = 80-130 g per U.F., or assuming a 300 kg bull needs and average 105 g/U.F., 2.5 x 105 = 273 g.

P (phosphorous) = 3-5 g per 100 kg live weight, or using an average of 4 g: live 300 kg weight x 4 = 12 g

Ca (calcium) = 5 g per 100 kg live weight, or 300 x 5 3 15 g

NaCl (sodium chloride; salt) = 5 g/100 kg live weight or 300/100 x 5 = 15 g.

3) Determine the energy value of the roughages the animal would normally consume. If left to graze freely, a bovine animal will consume between 10 and 20 kg of pasture (grass) per day. Since its digestive organs must process regular amounts of bulky material in order to function properly, it is reasonable to base the maintenance ration on roughages and the work or production ration on concentrate-supplements (grains and other low-fiber, high-energy feeds). It has already been established that 13.3 kg of green Sudan grass will furnish a 300-kg bull with its maintenance energy needs; in this example, this represents the average quality of mixed pasture grass that would be found early in the rainy season.

4) Determine the protein content of the roughage (maintenance) diet. Recall that for a work animal, protein, mineral and vitamin intake need not increase with production; only energy needs increase.

The following steps would be taken to find the number of grams of digestible protein contained in 13.3 kg of green Sudan grass:

a) One kg of 100% dry Sudan grass contains 4.2% protein, or 42 g of digestible protein per kg of dry matter.

b) In 13.3 kg of green Sudan grass there are 3.9 kg of dry matter:

*Ration consumed by bull

c) In 3.9 D.M., there are 164 g of digestible protein; in the 13.3 kg of fresh grass consumed by the bull, there are 164 g protein.

42 g x 3.9 kg = 164 g digestible protein

This ration is deficient in protein, since the requirement is 273 g (established earlier). However, in a wet season, free grazing situation, the animal would find a mixture of grasses that would meet all of its needs. The feeding of a protein supplement would be extremely important when the grasses begin to dry out, or if grazing time was limited to less than eight hours per day.

5) Determine the phosphorous value of the roughage.

a) One kg of 100% dry Sudan grass contains 0.12% phosphorous; or, 0.12% of 1000 g = 1.2 phosphorous per kg D.M.

b) 13.3 kg of green Sudan grass contains 3.9 kg D.M.; or, 3.9 x 1.2 = 4.7 g of phosphorous.

This ration is deficient in phosphorous, the requirement being 4 g per 100 kg live weight, or 12 g. The difference would probably be made up in the pasture mixture as long as grasses remained lush, but the stockman would be wise to furnish the animal with a mineral lick containing phosphorous year-round.

6) Determine the calcium value of the roughage.

a) One kg of 100% dry Sudan grass contains 0.34% Ca or 0.0034 x 1000 = 3.4 Ca per kg D.M.

b) 13.3 kg of green Sudan grass contains 3.9 x 3.4 g of Ca = 13.2 total Ca

The bull's Ca requirement is 5 g per 100 kg live weight, or 15 g total. Again, by providing them with a mineral lick, the owner ensures the animals' health regardless of fluctuations in grazing conditions.

7) Salt needs. While CEEMAT suggests that 5 g/100 kg live weight is sufficient for a working animal, it may be found that a bull consumes more if given free access to a block-especially during heavy work when salt is lost in sweat. Except in the case of salt-starved animals, the free-access system works well because animals will not normally consume more than they need. Phosphorous, Vitamin A and limited amounts of protein can be fed in a salt mix or block. The intake can be regulated by the feed formulation or texture of the block.

8) Calculate the work needs of the animal and determine the supplemental ration that will be fed.

A bull doing heavy work (plowing) needs 5/2 E, or 5/2 of its maintenance requirement. A 300-kg bull needs 5/2 x 2.6, or 6.5 U.F. per day.

In the example used, the bulky portion of the full ration consists of 13.3 kg of green Sudan grass; the grass has a U.F. value of 2.6. The supplemental work ration must provide about 4 additional U.F. if the animal is to get the required 6.5 U.F. These units can be supplied from any of the feeds listed in the table, but consideration would be given to these points:

a) Cost of feed. Grain is very expensive compared to grain by-products and other concentrate feeds. It is also in short supply during the work season; most of it has been used during the dry months.

b) Some feeds, particularly lush young pasture, legumes, and brans, have a laxative effect. Too much dry grain can also cause digestive trouble. It is generally advisable to feed a supplement made of a combination of various feeds.

c) Animals have individual preferences and may refuse to eat the supplemental ration as given. Precracking grains or adding salt, brewers' meal or bone meal to a ration may make it more palatable. The owner should make an effort to discover what the animal likes, what it digests easily, and when it will eat. Normally, an ox is fed its concentrate ration in the evening after it has grazed. However, a small portion of the ration may be given in the morning, or at noon if the animal has been allowed to graze and drink first. Animals do not work well when overly full and so it is preferable to have them eat at the end of the day.

d) Time of year determines the availability of certain feeds. Green corn or sorghum fodders are not available during the plowing season when they would be most useful. The farmer should store silage, hay and grain reserves for this heavy work period.

Suggested daily rations for a 300-kg bull doing heavy work (plowing) are given below. A 13 kg portion of mixed green pasture (early wet season grasses) has an approximate forage value of 2.5 U.F. and this quantity will be consumed if the bull is allowed 6-7 hours grazing time. In practice, 23 hours (grazing) would be given at mid-day (after the morning work session) and the remainder would be given in late afternoon/early evening.

Examples of Daily Rations for a 300-kg Bull:


(approximately equal to)

13 kg mixed green pasture

2.5 U.F.

2 kg mixed cracked corn and sorghum


1 kg peanut cake


2 kg legume hay (night fed at stable)



Total: 6.5 U.F.



a.m.-1 kg brewers' meal mixed in 4 liters water

1.0 U.F.

13 kg mixed green pasture


4 kg mixed green chop (night-fed cut past-ture)


2 kg cottonseed



Total: 6.5 U.F.



a.m.-1 kg peanut cake

1.0 U.F.

13 kg mixed green pasture


2 kg legume hay


2 kg mix wet brewers' meal and cracked corn



Total: 6.5 U.F.


Recommended rations and feeding practices

The rations given below are intended to serve as general guidelines for establishing a successful feeding program. When formulating rations, consider the factors which may lower the benefits of the ration, including:

• Environmental factors which affect the composition and hence nutritional value of food: soil, climate, seasonal changes, insect damage, mold.

• Animals will adapt to a wide variety of feeds, but the change must be gradual to prevent the animal from going off feed.

• Digestibility: Individual digestive ability can be affected by age, teeth, condition of digestive organs and functions, presence of parasites, quality of food. In feeding ruminants, changes in diets from high roughage to low roughage (high concentrate) affect the population of microbes in the rumen. Rapid changes can result in serious upsets in the animals' physiology. Any major changes should be made gradually over a two week period.

Rations should be altered as experience and observation suggest.

In addition to the recommended guidelines, some specific suggestions follow on how and when to feed animals.

Note: Research and practical experience have demonstrated that the nutritional needs of animals and the nutrient values of various diets can be calculated quite accurately


Oxen need pasture, grain, and may need additional protein and mineral supplements in order to meet nutritional requirements. Supplements are expensive but may be practical and necessary (especially if mineral deficiencies are present).

Here is an example of a feeding schedule for a working ox kept on pasture:

5:30 am

1/2 kg cracked corn + 1/2 kg peanut cake (mixture)

(7-12 noon)


12-4 pm

short drink followed by free grazing (super vised). Let the animals graze toward a stream or well and give it free access to water.



6 pm

short drink

7 pm

mixture containing 1-1/2 kg crushed grain sorghum + 1/2 kg peanut cake or cottonseed meal

8 pm

free access to water and mineral block; stall feeding of 2 kg of legume hay. Water, hay and mineral block are left where the animal can reach them during the night.


Bovine animals need roughage (pasture grass, hay) in order to maintain basic nutritional and energy needs. Most oxen grazing on young pasture can consume enough feed and nutrients to maintain a healthy status in six to eight hours Oxen that do not have sufficient time to graze must be fed cut pasture in the stall at night.


Chart A approximates the amount of roughage an ox needs daily.

Other types of roughage which oxen eat include fresh legumes, grasses, hay, straw, corn or sorghum fodder, and tree fodder. These products should be included in the diet whenever possible.

When work schedules do not permit adequate grazing time, oxen should be stall-fed hay or cut green pasture at night. Estimate the amount of pasture to feed at night by using the following method:

1) Estimate the amount of pasture consumed daily by the animal. For example, assume an ox eats 3 kg of pasture per hour (rainy season; grass in abundance). Multiply the number of hours the animal grazed by three.


x 3

= 15

(number of hours grazed during day)

(kg of grass eaten per hour during rainy season)

(kg grass eaten while grazing during the day)

2) Subtract the amount of pasture eaten during free grazing from the total amount it needs. This gives the approximate kg of pasture to cut and feed at night.


- 15.0

= 7.5

(kg pasture needed by 300kg bull-obtained from Chart A).

(kg pasture eaten during free grazing)

(kg roughage to feed at night)

3) Establish a suitable standard of measure by using a bucket or container. Pack the bucket with grass, weigh it, and then subtract the weight of the bucket. Check the weight of the measure every few weeks, adjusting the amount to allow for changes in moisture content of the grass.

Grain and Other Concentrates

Grain is the seed portion of cereal plants such as corn, sorghum, millet and rice. Grains are low in fiber and thus are called "concentrates". Grains have a high starch content (carbohydrates) which is an important source of energy to work animals that have limited time to graze. Other concentrates include beans and mill by-products, such as peanut cake, cottonseed meal, and brewers' meal (described on page 185).

Amount of Concentrate to Feed

For working animals, use the table below (Chart B) to determine the amount of concentrates to feed. This should provide sufficient energy needed by working animals. Feed intake varies with the weight of the animal and the work load. The terms "light," medium" and "heavy" are used to define the work load.

Hours of Work





Ox pulling 1/8 its weight




Donkey pulling 1/5 its weight




Horse pulling 1/7 its weight




The concentrates may be decreased by 1 kg if the roughage intake includes 2 kg of legume hay or 5 kg of green legumes.

For non-working (idle) oxen, feed the following amounts of concentrates:

• Off-day during the work season-light work ration (see Chart B).

• Off-season or dry season-onehalf light work ration (each day).


Weight of ox

Amount of Grain to Feed per Day (in kg)

(in kg)

At Light Work

At Med. Work

At Heavy Work





















The figures are based on maintenance needs of ruminant animals (see page 176) and the assumption that one kg of grain (corn, sorghum, millet, and/or barley) has a forage value equal to one (one kg of 100% dry grain = 1 U.F.; see explanation of forage value on page 175.

When to Feed Concentrates

• Working oxen: Feed 1/4-1/3 of the ration in the morning, the rest in the evening. Do not feed when the animal is hot (i.e., immediately after work) or after it has had large quantities of water.

• Non-working oxen: Feed the entire ration in the evening when the animal returns from pasture.

How to Feed Concentrates

Feed concentrates in a container that cannot be knocked over. Stake or corral oxen so each has access to a separate container. This way you can see how much and what each animal eats. Also, it keeps more aggressive individuals from taking other animals' food.

Experiment with grains to find out which ones an animal likes. If an ox refuses to eat grain, crush it and add a little salt. Leave it near the ox throughout the night. A little water added to cottonseed will make it a little more palatable.

Give the animal fresh rations every day. Keep the feeding container clean.

Feed Supplements

A diet consisting of high quality grass, hay, and grain should supply protein, vitamins, and minerals necessary for overall health. However, nutrition deficiencies can result from unavailability of feeds or conditions which affect the quality or digestibility of feed. The following supplements should be fed to provide balanced diets:

• Protein: Mature oxen should be provided with concentrates that supply additional protein. Examples of this would include feeding a daily allowance of one of the following: 1/3 kg peanut cake, 3/4 cottonseed meal, 1 kg wet brewers' meal, or 1-1/2 kg sorghum bran.

• Minerals and salt: Animals should have free access to a salt block lick wich contains two parts calcium, one part phosphorous and one part salt. If a lick is not obtainable, mix bone meal (or other source of calcium and phosphorous) and salt in the feed. (For quantities, see Appendix B, page 192.)


Equine animals must be fed with regard to their particular needs and digestive capabilities. While an ox can be fed once at the end of the day, a working horse should be given feed in small quantities. This practice facilitates complete, regular digestion of nutrients and ensures that the animal will be comfortable while working.

Horses and Mules

1) Feed the right amount. Total daily consumption of roughages and concentrates combined should be between 0.8 and 1.0 kg for every 40 kg of live body weight. A 320 kg horse, for example, should get between 6.4 and 8 kg of feed per day.

2) Idle horses are fed chiefly on grass and hay. One-third to one-half of the roughage should be grass or legume hay. (Straw should not be fed to horses, for they do not have the ability to digest it.)

3) For working horses, about half of the total ration should consist of roughage, half grain and other concentrates.

4) Working horses should be fed ration in three equal parts at morning, noon and night. Idle horses may be given the entire ration in the evening, or half in the morning and half in the evening.

5) Grain should be partially crushed to aid digestion.

6) A few handfuls of chopped straw or dry corn leaves can be offered along with the grain. These feeds encourage the animal to chew more thoroughly.

7) Both idle and working horses need one-third of a high protein supplement like bran, brewers' meal or cottonseed meal mixed with the grain. Brewers' meal can be mixed in water and given as a drink.

8) Allow animals free access to a mineral/salt block lick, or add bone meal and salt to the concentrate ration as recommended in Appendix B, page 192.

Recommended Rations

For a 300-kg horse the recommendations are:

Idle: 3-1/2 kg cured grass hay + 2 kg legume hay + 1/2 kg grain mixed with several handfuls of wet brewers' meal with the grain;


4 kg green pasture containing legumes + 1 kg grain + 1/2 kg cottonseed meal;


3 kg dried pasture grass (standing hay) + 2 kg legume hay + 1/2 kg grain + 1/2 kg sorghum bran.

Medium work: 2 kg green pasture + 2 kg legume hay + 3 kg grain + 1/2 kg brewers' meal;


2 kg green pasture (legumes + grass) + 2 kg cured grass hay + 3 kg grain + 1/2 kg cotton

seed meal (or cowpea meal or peanut cake).

As workload increases:

• Replace cured grass hay or green pasture with legume hay.

• Increase the concentrate meal portion by l/2 kg and decrease the grain portion by 1/2 kg.

As workload decreases:

• Decrease the grain portion and increase the roughage portion.

• Adjust the ration according to the weight of the animal using the rules given above (1-3). Use the rations given for the 300-kg horse as a guide for establishing the proportions of various feeds.


Generally speaking, donkeys are fed like horses. However, donkeys can subsist on very coarse forages like straw, crop stubble, and leaves and stems of desert plants. Unlike horses, they will not overeat when given free access to pasture or grain. They prefer to nibble throughout the day.

Donkeys can be fed according to the following rules:

1) Allow free access to pasture whenever possible. Otherwise, supply the donkey with fresh hay and straw.

2) Provide a 1/3-kg mixture of grain plus oilcake daily.

3) Provide a 90-llO kg working donkey with additional grain along with the above rations, according to the following guidelines:

light work: l kg additional grain

medium work: 1-1/2 kg additional grain

hard work: 2 kg additional grain

(Larger donkeys should be given grain in proportionate amounts.)

4) Provide free access to mineral/ salt lick and water as with horses.