Feeding takes about 70% – 75% of the total cost of production of a poultry business. The success of a poultry business is determined by the quality and not the quantity, per se, of the feed given.
Though, quantity of the feed really matters but the efficiency of the quantity is enhanced by the quality of the feed. Poultry birds are very sensitive animal; the quality of the feed they eat determines their output. Also, what they eat is determine by some factors; these factors are: - Species
- Age and
- The purpose of production – whether the birds are kept for meat or egg production.
Poultry require array of nutrients to enhance their physiological development and productivity. Poultry birds need a steady supply of nutrients like: energy, protein with essential amino acids, essential fatty acids, minerals, vitamins and, most important, water. Poultry birds obtain energy and required nutrients through the digestion of natural feedstuffs, but minerals, vitamins and some key essential amino acids (lysine, methionine, threonine and tryptophan) are often offered as synthetic supplements. Below is the comprehensive guide to poultry feed and feeding; showing all the required nutrients and respective sources.
Take a look…
Energy
Energy is very important to poultry birds; they need energy to enhance their productivity. At times, energy supply takes about 60% of the feed composition depending on the type of animal and production and phase purpose. Poultry birds derive energy from simple carbohydrates and fat majorly. Grains are the major source of energy in poultry feed; they are maize, rice, millet, sorghum, oat etc. Maize is considered the best energy provider and the standard for energy requirement for poultry feed. Maize contains no anti-nutritional factors that tend to reduce the digestibility of the feed in the birds’ system. Unlike other energy source like sorghum that contains an anti-nutritional factor called Tannin. However, sorghum can be used to formulate poultry feed but it must not be the sole source of energy in the feed. Poultry birds cannot digest and utilize some complex carbohydrates, such as fibre, because of the simple nature of their stomach.
Poultry birds eat primarily to satisfy their energy needs, provided that the diet is adequate in all other essential nutrients. The energy level in the diet is therefore a major determinant of poultry birds’ feed intake. When the energy level changes, the feed intake will change, and the specifications for other nutrients must be modified to maintain the required nutritional intake. For this reason, the dietary energy level is often used as the starting point in the formulation of practical diets for poultry. Different classes of poultry need different amounts of energy for metabolic purposes, and a deficiency will affect their productivity.
Protein and amino acids.
Protein is another major nutrient needed in relatively large quantity by poultry birds. Protein plays major role in the growth and development of poultry feed. The function of dietary protein is to supply amino acids for maintenance, repair of worn out tissues, muscle growth and synthesis of egg protein.
Poultry birds need 20 amino acids to perform optimally and enhance their physiological development. Ten of these are either not synthesized at all or are synthesized too slowly to meet the metabolic requirements, and are designated as essential elements of the diet. These amino acids have to be supplied in the diet. From a physiological point of view, all 20 amino acids are essential for the synthesis of various proteins in the body. The essential amino acids for poultry are: lysine, methionine, threonine, tryptophan, isoleucine, leucine, histidine, valine, phenylalanine and arginine. In addition, some consider glycine to be essential for young birds.
Cysteine and tyrosine are considered semi-essential amino acids, because they can be synthesized from methionine and phenylalanine, respectively. Of the ten essential amino acids, lysine, methionine and threonine are the most limiting in most practical poultry diets. Poultry do not have a precise requirement for protein. However, an adequate dietary supply of nitrogen from protein is essential to synthesize non-essential amino acids. The amino acid requirements of poultry are influenced by several factors, including
- Production level,
- Genotype,
- Sex,
- Physiological status,
- Environment and
- Health status.
For example, high levels of lean meat deposition require relatively high levels of lysine. High levels of egg output or feather growth require relatively high levels of methionine. Common sources of protein in poultry diet include: fishmeal, soybean, soybean meal, maize gluten meal, cottonseed meal, groundnut cake etc.; these are rich sources of protein in animal feed. Some contain anti-nutritional factors like whole soybean and cotton seed; the anti-nutritional factors are always denatured through heat treatment before inclusion into poultry diet.
Fats and fatty acids
Fat is another important component of animal feed; they are needed in the diet to provide energy, enhance feed palatability and reduce dustiness. Also, because of the greater energy density of fat compared with carbohydrates and protein, poultry diets usually include fats to achieve the needed dietary energy concentration. Fat takes about 3 - 5 percent of the whole diets. Poultry do not have a specific requirement for fats as a source of energy, but a requirement for linoleic acid has been demonstrated. Linoleic acid is the only essential fatty acid needed by poultry; linoleic acid’s main effect in laying birds is on egg size, it increases the egg size. Common sources of fats and oil includes: Palm oil slurry, groundnut cake etc.
Minerals
Minerals are another cogent component of animal diet; though, needed in minute quantity. They are needed for the formation of the skeletal system, for general health, as components of general metabolic activity, and for maintenance of the body’s acid-base balance. Calcium and phosphorus are the most important minerals for poultry birds; they are classified as macro-minerals, along with sodium, potassium, chloride, sulphur and magnesium.
That are needed in relatively higher quantities unlike other minerals; they aid in egg shell formation and strengthen the bones of the bird. Macro-minerals are elements required in the diet at concentrations of more than 100 mg/kg. Calcium and phosphorus are necessary for the formation and maintenance of the skeletal structure and for good egg-shell quality. In general, 60 to 80 percent of total phosphorus present in plant-derived ingredients is in the form of phytate-phosphorus.
Under normal dietary conditions, phytate phosphorus is poorly utilized by poultry owing to the lack of endogenous phytase in their digestive enzymes. It is generally assumed that about one third of the phosphorus in plant feedstuffs is non-phytate and is biologically available to poultry, so the phosphorus requirement for poultry is expressed as non-phytate phosphorus, rather than total phosphorus. A ratio of 2:1 must be maintained between calcium and non-phytate phosphorus in growing birds’ diets, to optimize the absorption of these two minerals. The ratio in laying birds’ diets is 13:1, because of the very high requirement for calcium for good shell quality.
Dietary proportions of sodium (Na), potassium (K) and chloride (Cl) largely determine the acid-base balance in the body for maintaining the physiological pH. If a shift occurs towards acid or base conditions, the metabolic processes are altered to maintain the pH, with the likely result of depressed performance. Birds exposed to heat stress consume more water, and are better able to withstand heat when the water contains electrolytes. The replacement of part of the supplemental dietary sodium chloride with sodium bicarbonate has proved useful under these conditions or the inclusion of coconut water in the drinking water. Trace elements like: copper, iodine, iron, manganese, selenium, zinc and cobalt; function as components of larger molecules and as co-factors of enzymes in various metabolic reactions. These are required in the diet in only very small amount. Sources of Minerals are: Liver, Oyster shell, sea food etc.
Vitamins
Vitamins are also essential in poultry birds’ growth and production. They are classified as fat-soluble (vitamins A, D, E and K) and water-soluble (vitamin B complex and vitamin C). All vitamins, except for vitamin C, must be provided in the diet. Vitamin C is not generally classified as a dietary essential as it can be synthesized by the bird. However, under adverse circumstances such as heat stress, dietary supplementation of vitamin C may be beneficial. The metabolic roles of the vitamins are more complex than those of other nutrients. Vitamins are not simple body building units or energy sources, but are mediators of or participants in all biochemical pathways in the body.
Water
Water is the most important, but most neglected nutrient in poultry nutrition. Water has an impact on virtually every physiological function of the bird. A constant supply of water is important to:
- Aid digestion of feed;
- Aid absorption of nutrients;
- Aid the excretion of waste products; and
- Aid the regulation of body temperature.
Water constitutes about 80 percent of the body. Unlike other animals, poultry eat and drink all the time. If they are deprived of water for even a short time, production and growth are irreversibly affected. Water must therefore be made available at all times. Both feed intake and growth rate are highly correlated with water intake. Precise requirements for water are difficult to state, and are influenced by several factors, including ambient conditions, and the age and physiological status of the birds. Under most conditions, water intake is assumed to be twice the amount of feed intake.
Drinking water temperatures should be between 10 and 25 °C. Temperatures over 30 °C will reduce consumption. The quality of water is equally important. Quality is often taken for granted, but poor water quality can lead to poor productivity and extensive economic losses. Water is an ideal medium for the distribution of contaminants, such as chemicals and minerals, and the proliferation of harmful microorganisms. Water quality for poultry can be a major issue in arid and semi-arid regions where water is scarce. In particular, underground water in these areas can have high levels of salt. Saline drinking-water containing less than 0.25 percent salt is tolerated by birds, but can cause sodium toxicity if water intake is restricted.
This is the breakdown of poultry feed and importance of different components of the feed. This guides in poultry feed formulation and manipulation; feeding poultry birds is very important and helpful to the productivity of the birds, provided the right quality and quantity are attained.
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