Nutrients Requirement of Poultry and their Sources

October 9, 2023 Agric4Profits

Nutrition is the process which provides nourishment to a living organism. This implies the provision of certain food elements (nutrients) that the body of the organism absorbs and uses to perform its normal function associated with life as well as storing the excess in its tissue.

The Nutrients Required by Poultry Include the Following:

1. Energy

2. Protein

3. Vitamins

4. Minerals

5. Water

1. Energy

The energy requirement of poultry is supplied from carbohydrates and lipids. In adverse conditions, protein can also be broken down to supply energy.

The energy in poultry is normally expressed in units of metabolizable energy per unit weight e.g. kilo joule/gram (KJ/G) or requirement in terms of metabolizable energy per day (KJ/day).

The metabolizable energy refers to that portion of the feed which is available to the bird for the production of meat and egg and for the maintenance of vital function and body temperature.

Birds are usually given free access to feed and they eat to satisfy their energy requirement. The more increase in energy value of feed the less its intake and the reverse is true.

Sources of Energy

Maize; Sorghum; Millet; Wheat; Barley; Maize bran; Wheat bran; Brewers dried grain (BDG); Cassava; Yam; Vegetable oils (groundnut coconut, soybean cotton seed e.t.c.)

2. Protein

Proteins are nitrogen-containing compounds. They promote growth and flesh formation. Proteins are made up of units of amino acids.

The synthesis of proteins in the body requires about twenty different amino acids. Ten of these amino acids cannot be synthesised by the birds and must be provided in the diet. These are termed essential amino acids. Examples include:

Phenylalanine; Valine; Threonine; Tryptophan; Isoleucine; Methionine; Histidine; Arginine; Leucine; Lysine

The non-essential amino acids are:

Alamine, Aspartic acid, Glycine, Proline, Hydroxyl praline, Tyrosine, Serine, Cysteine, Cystine, Glutamine.

Of all the essential amino acids. Lysine, methionine and tryptophan are called critical amino acids because they are the most limiting amino acids in feedstuff.

In the general deficiency of essential amino acids leads to poor growth, poor egg production and low feed utilization.

Sources of Proteins

Sources are of two types, plants and animal sources.

Plant sources

Sunflower meal, Palm kernel meal, Soya bean, Bambara nut, Cotton seed cake, Ben seed meal, Bambara nut meal, Locust bean meal, Shear butter meal, Groundnut cake, Soybean meal, Cowpea e.t.c.

Animal sources

Fish meal, Meat meal, Maggot meal, Termite meal, Chicken offal meal, Grasshopper meal, Feather meal, Meat and bone meal, Blood meal etc..

3. Water

Water is the most important nutrient for farm animals. The body of a chicken is composed of at least 70% of water as also the egg. It is usually made freely available to poultry.

The water intake of birds varies with age, temperature, size, diet and rate of egg production.

Table: Estimated water intake (at 21◦C) of chicken of various ages:

Age (week)	water intake/100 birds (litre/day)
0-2	4 -5
2-5	7 -10
5-10	15
10-20	18 -22
Adult layers	20 – 30

Lack of water can seriously retard the growth rate and impaired egg production. In tropical countries, water deprivation can lead to death within a very short period of time

4. Minerals

Minerals are inorganic substances required by farm animals to build their skeleton and perform various metabolic functions in the body. Minerals are classified into two groups based on their level of requirement.

Macro or major elements are minerals required in relatively large quantities which are calcium, potassium, magnesium, sodium chlorine and sulphur.

Micro or minor elements are required in small quantities. These are iron, zinc, copper, molybdenum, selenium, iodine, manganese, cobalt and fluorine. The major minerals in poultry feeding are calcium and phosphorus.

Read Also: Digestive System of Poultry

The common sources of minerals include:

Bone meal, Oyster shell, Limestone, Di calcium phosphate, Common salt, Wood ash, Green grass, etc.

The micro minerals are usually incorporated as pre-mix in which form they contain most of the trace minerals in the right proportion required by the various classes of chicken.

5. Vitamins

Vitamins are organic compounds not synthesized by the body but are essential for normal growth and good health. They are required in small amounts. There are thirteen vitamins required by poultry. They are fat-soluble and water-soluble vitamins.

Fat-soluble vitamins include:

Vitamin A, D, E, K

Water soluble vitamins include:

Thiamine (B1), Riboflavin (B2), Pyridoxine (B6), Pantothenic acid, Nicotinic acid

Biotin Folic acid, Cobalamine (B12), Ascorbic acid

Some of these vitamins are available in green feeds, grains and animal proteins.

All are available in synthetic form (vitamin premix).

6. Feed additives

Anti-oxidants: examples include ethoxyquin or butylated hydroxytoluene at the rate of 112g per tone of feed to prevent oxidation of vulnerable vitamins, especially vitamin A.

Coccidiostats: These are usually introduced at prophylactic levels in broilers’ diets according to the recommendation of the manufacturers. It is completely withdrawn towards the end of the fattening period.

Recommended Nutrient Allowance for Poultry under Tropical Climatic Conditions

Table: Nutrient allowance for poultry under tropical climatic conditions

Nutrients	Chicken ration	growers ration	Layers ration	Broiler starter	Broiler finisher
Crude protein (%)	19.5	15.0	16.5	22.0	20.0
Crude fibre (%)	5.0	6.0	5.0	5.5	5.5
Metabolizable energy(kcal/kg)	2700	2650	2600	850	2900
Calcium (%)	1.0	0.80	3.20	1.0	0.80

Phosphate (%)	0.45	0.50	0.50	0.70	0.50
Sodium (%)	0.15	0.10	0.15	0.15	0.12
Vitamin A (iu)	5000	3500	4000	5000	3500
Lysine (%)	100	0.65	0.70	1.30	1.10
Methionine (%)	0.40	0.30	0.35	050	0.40
Tryptophan (%)	0.20	0.15	0.18	0.25	0.20

Feed requirement and body weight of Broilers

Table: Feed requirement and body weight of Broilers

Age (weeks)	Average weight/bird (Kg)	Feed requirement/ 100 birds (kg)	Feed requirement cumulative/100 birds
1	0.036	10	10
2	0.080	18	28
3	0.140	21	49
4	0.200	26	75
5	0.350	39	140
6	0.510	52	166
7	0.90	58	224
8	1.5	67	286
9	2.1	67	358
10	2.5	71	424

Growth rate, feed intake and floor space requirement of pullets

Table: Growth rate, feed intake and floor space requirement of pullets

Age week	Body weight(g)	Feed/bird/Day (gm)	Floor space cm2/ bird
1	45	10	232
2	90	16	232
3	126	22	232
6	270	44	464
10	427	63	0.10
15	652	69	0.18
18	780	75	0.30
20	850	79	0.30

Note: An average layer would consume 100gm of feed per day or up to 130gm for heavy breeds.

In conclusion, the fowl is a simple stomach animal and digestion starts in the mouth, ends in the small intestine and nutrients are absorbed through its wall.

The caecum is for digestion of fibre and water absorption, while the large intestine is for absorption of water and storage of faecal matter.

The energy required by poultry is supplied from carbohydrates, lipids and sometimes proteins.

Essential amino acids are those amino acids that cannot be synthesized by the bird and must be provided in the diet. In poultry, lysine, methionine and tryptophan are the critical amino acids because they are the most limiting amino acids in feedstuff.

Minerals are classified into macro or major and minor or micro-elements. Those minerals required in large quantities are the major or macro minerals while those required in small quantities are the micro or minor minerals. Vitamins are required by poultry and they are either fat or water-soluble.