ANIMAL NUTRITION

Meaning of nutrition

The art and science of feeding farm animals including plants to achieve healthy growth is known as nutrition.

Feed is the food or meal eaten by farm animals and the food elements contained in animals feeds are called nutrients. These various elements include oxygen, hydrogen, carbon, phosphorus, potassium, magnesium, nitrogen, calcium, sulphur,iodine, iron, chlorine, cobalt, sodium, manganese, copper, zinc and molybdenum.

 

Food/feed nutrients and classification

Food nutrients are chemical elements present in feeds fed to animals. These elements have been mentioned above. Farm animals need food for production, growth, energy, performance of body functions and general repairs.

There are six classes of food nutrients/constituents which are required by farm animals.

These include:

1. Protein.
2. Carbohydrate.
3. Fat.
4. Mineral.
5. Vitamin.
6. Water.

 

Proteins

Composition: Proteins are chemically composed of carbon, hydrogen, oxygen, nitrogen and sulphur. They are made up of sub-

Proteins are classified according to their composition as follows:

• Simple proteins: These are proteins which provide only amino acids on hydrolysis e.g. albumin and myosin.
• Conjugate proteins: These are proteins that yield organic and inorganic components in addition to amino acids e.g. mycoprotein and nucleoprotein.

 

Sources of Protein

Sources of proteins are groundnuts, beans, peas, groundnut cake, melon cake, cotton seeds, blood meal, lean meat, albumen of egg and milk.

 

Functions of Protein

1. Used in the replacement of worn out tissues.
2. Used in the building of animal cells (tissues).
3. Used in the formation of hormones and enzymes.
4. Assist in the production of wool, milk and egg formation.

 

Effects of protein deficiency

The effects of protein deficiency in the body of farm animals are given below.

1. It causes poor and retarded growth.
2. It causes poor reproductive process.
3. It leads to kwashiorkor in all farm animals.
4. It results in poor functioning of enzymes and hormones.

 

Carbohydrates

Composition: The chemical constituents of carbohydrates are carbon, hydrogen and oxygen. Carbohydrates are classified into:

Monosaccaharides (or simple sugars): They are easily digested e.g. glucose, fructose and maltose.

Disaccharides (or complex sugars): They are not readily digested e.g. sucrose, maltose and cellulose. They have more complex molecular units than simple sugars. In fact, they are formed from simple sugars by condensation reaction. Excess carbohydrate is converted to fats.

 

Sources of carbohydrates: The sources of carbohydrates are:

1. Cereals e.g. maize, guinea corn, millet etc.
2. Virtually all sweet fruits juice and sugar cane.
3. Roots and tubers e.g. cassava, yam, potato.
4. Some roughage.

 

Fats

Composition: Fats are composed of carbon, hydrogen and oxygen. Fats are also called lipids. Fats are broken down on digestion into fatty acids and glycerol.

 

Sources of fats

The sources of fats include groundnut cake, oil palm kernel cake, linseed cake, coconut cake, cotton seed residues, melon seed, cashew nut.

 

Functions of fats

1. Provide energy for movement.
2. They insulate the body from cold and therefore help to maintain the body temperature.
3. Essential fatty acids are needed for growth.

 

Minerals (ash)

Composition: Minerals also called ash, are inorganic compounds existing in combined state as ions in solutions. They are classified according to the quantity required by the body.

• Major minerals: Major minerals are needed in large quantities e.g. phosphorus, potassium, calcium, magnesium, iron, chlorine and sulphur.
• Minor minerals: These are required in small quantities e.g. Iodine, copper, manganese and zinc.

 

Sources of minerals

1. Green plants.
2. Supplements such as bone meal, oyster shell, blood meal.
3. Salt licks.

 

Functions of minerals

1. They promote digestion, absorption and excretion.
2. They are needed for reproduction, lactation and growth.
3. They regulate acid-base relationship of the body fluid.
4. They promote formation of bone, teeth etc.
5. They are needed for protein synthesis.

 

Vitamin

Composition: Vitamins contain carbon, hydrogen and oxygen. Vitamins are organic substances which animals need in small quantities for normal health, growth and reproduction. They are also called welfare food substances. They are classified into two groups.

• Water soluble vitamins e.g. vitamins B and C.
• Fat soluble vitamins e.g. Vitamins A, D, E and K which dissolve in fats.

 

Sources of vitamins

1. Green fodder or green vegetables.
2. Cod-liver oil.
3. Fruits.
4. Fish meal.
5. Cereals.

 

Functions of vitamins.

1. Prevent diseases.
2. Encourage growth.
3. Help general functions of the body.

 

Water

Composition: It consists of hydrogen and oxygen. Water is the major constituent of the blood and body fluids. It constitutes about 75% of the body weight of the adult animal and about 95% of the newly born baby.

 

Sources of water

1. Drinking water.
2. Fresh fodder and grasses.
3. Metabolic water.

 

Functions of water

1. Regulates body temperature.
2. Dissolves food nutrients.
3. Removes waste products from the body.
4. Lubricates joints.
5. It helps in food digestion.

 

Effects of water deficiency

A deficiency of water in the body of farm animals causes the following:

1. Dehydration: This is a situation when farm animal loses water to the environment without replacement which makes, the animal to become flaccid.
2. Restlessness.
3. Low production in farm animals in terms egg, milk and meat.
4. Slow growth.
5. Paralysis and eventual death in farm animals.

 

Types of feeds/feeding stuffs

Feeding stuffs are classified according to their predominant nutrients. Livestock rations are compounded from the groups, depending on the type of animal.

 

Animal feeds can be classified into four (4) main groups.

These are:

1. Concentrates.
2. Succulents.
3. Roughages.
4. Supplements and additives.

 

Concentrates: These are animal feeds low in fibre and water content. They are feed mixtures which provide all the primary dietary needs of proteins, carbohydrates, fats, some vitamins and minerals.

Examples include:-

1. Cereals like maize, rice, guinea corn, millet, bran. These are also called basalfeeds or energy concentrates. A basal/energy concentrate is the feed that has crude fibre content less than 18%.
2. Animal products e.g. blood meal, bone meal and fish meal. These are animal protein concentrates. Protein concentrate is a type feed that has crude fibre content less 18% like basal concentrate.
3. Oil seeds and cakes e.g. groundnut cake, soybean cake, soybean cake, cotton seed cake, coconut cake.
4. Leguminous seeds such as soybean and groundnut, cowpea etc. These are plant protein concentrates mainly fed to monogastric animals.

 

Characteristics of Basal/energy feed (carbohydrate concentrate) and Protein Concentrate

Carbohydrate Concentrate

1. High in Carbohydrate or fat energy.
2. Low in protein.
3. Low in fibre.
4. High digestible.
5. Low in minerals.

 

Protein Concentrate

1. High Protein.
2. Low Carbohydrate/fat.
3. Low fibre.
4. Highly digestible.
5. Low in minerals.

 

Succulents: Succulents are very high in water and easily digested by animals. They are also high in carbohydrates. Examples include roots, tubers, some plants such as water leaf and sweetners e.g. Cane molasses and crude sugar.

 

Roughages: Roughages are animal feeds characterized by high fibre content (more 18% crude fibre). They are usually industrial by products. Examples are fodder, hay, silage, straw, e.g. Maize and Guinea corn stalk.

Characteristics of roughages

1. Very high in fibre.
2. Low in digestible carbohydrate/low in energy.
3. Low in protein.
4. Poor/Low digestibility.

 

Explanation of different forms of roughages

1) Dry roughages: The dry roughages include

• Hay: This is a dry roughage. It refers to the aerial part of the young and succulent grass or herbage cut and dried for feeding ruminant animals during the dry season, in area were green pasture/grasses are not easily available.
• Straw: This is also dry roughage which refers to aerial part of grass or harvested crops cut and stored for future use. Wet roughages are called soilage and silage respectively.

 

2 ) Wet roughages: The wet roughages include

• Soilage: This is wet roughage which means theprocess of cutting fresh or succulent grasses and legumes from the field and fed to animals in their pens. Soilage is also known as zero grazing in the sense that animals are not permitted to go out to feed on the grasses rather the grasses are cut and taken to them in their pens/paddocks.
• Silage: This refers to the preservation of green and succulent forage crops usually carried out under anaerobic condition.

 

Feed Supplements and Additives: These are feeds and substances which are required in small quantity to add nutrients or growth promotion substances which may be deficient in rations of livestock.

Examples of supplements are groundnut cake, cotton seed cake, fish meal, blood meal, bone meal, salt licks, vitamins and minerals while examples of additives include antibiotics such as terramycine and auromycine, hormones and amino acids.

 

Characteristics of mineral/vitamin supplement

1. Low in energy.
2. Low in Protein.
3. Low in Fibre.
4. High in vitamin/mineral.
5. For growth and development.
6. Aids resistance to diseases.
7. Aids in food digestion.

 

Ration and types of rations

A ration is feed given to a farm animal per unit time. Rations are classified according to the purpose they serve in the animal body. These are:

1. Maintenance ration.
2. Production ration.
3. Balanced ration.

 

• Maintenance ration: Maintenance ration is a ration which contains nutrients to enable the animal carry on normal body functions or activities without gaining or losing weight. Examples is finished beef cattle and broiler feeds.
• Production ration: This is a ration which in addition to supplying nutrients for maintenance, also supplies additional nutrients to enable the animal produce a specific product or products such as milk (for dairy cows) and eggs (for laying hens) or even growth in young animals. Examples is feed for dairy cattle, layer, fattening materials.
• Balanced ration: A balanced ration is one which contains all the nutrients required by particular animal in the right proportion. A balanced ration should compose protein, carbohydrates, fats, minerals, vitamins and water.

 

Malnutrition

Malnutrition is a condition in which an animal shows evidence of nutritional deficiency. It occurs when an animal is fed a ration which is deficient in one or more nutrients. For example, a ration which is deficient in protein causes reduced growth. Other examples of malnutrition include rickets, allopesia (loss of hair), crazy chick diseases (Encephalomalacea).

 

Effects of malnutrition

1. Low production.
2. Retarded growth.
3. High mortality rate.
4. Susceptibility to diseases.
5. Physical deformities e.g. Rickets in young animals.
6. Death of animals.

 

Factors considered when formulating animals rations

1. The purpose for which the animal is being kept.
2. The class of animal.
3. The age of the animal.
4. The animal’s condition of health.
5. Physiological state of the animal e.g. Weaning, pregnancy.

 

Feeding equipment/tools for livestock production

Different forms of feeding and drinking toughs or containers exist. They include wooden feeding trough, and aluminum drinking rough, bucket, silage fork and milk chute.