Factors Influencing Feed Consumption In Chickens

Factors To be considered In Poultry Feeding

1. Feed must contain all essential nutrients in right amounts and proportion as required.

2. Different standards per age/breed should be followed.3. Palatability of the ingredients. 4. Unlike ruminants, poultry completely depend upon the

dietary sources for all nutrients (essential AAs., vit. B groups & vit. K).

Factors To be considered In Poultry Feeding

5. Include agro-industrial by-products to minimize cost of the ration.

6. Optimum level of ingredient inclusion as many of ingredients have a deleterious effect at higher levels.

7. Optimum Ca:P ratio for different purposes.

Factors Affecting Feed Intake

Factors Affecting Feed Intake:

1. Type of Bird2. Age of Bird3. Growth / production rate4. Energy Content of Feed5. Particle Size of Feed6. Water Availability to Birds7. Health Status of Birds/Diseases8. Ambient temperature9. Stress10. Fiber content of the feed

1- Type Of Bird

Meat producing birds Egg producing birds Dual type birds Hybrids-Breed cross or strain crosses Fancy or ornamental birds

2- Age of Bird

Nutrient requirements are related to both body weight and the stage of maturity.

In later stages feed intake will increase gradually because bird requires feed for maintenance and production purposes and bird has to overcome the stress of egg/meat production.

3- Growth / Production rate

The growth of meat type birds is rapid as compared to egg type birds, so, feed intake will be more and fast in meat producing poultry.

Feed consumption in layer birds will increase as chicks becomes growers and grower becomes layers.

4- Energy Levels In The Ration

Energy level feed intake Energy level feed intake

5- Particle Size of Feed

It is inversely proportional to the feed consumption.

Birds tend to eat larger particle size as chickens has the ability to pick the larger cereal grains.

The feed consumption will improve as the particle size is reduced to medium by mash, pellet and crumble preparation compared to whole grain.

6- Water Availability to Birds

Water is the most essential although the requirement value cannot be easily determined as with other nutrients.

The water requirement of the meat producing birds depends upon:1. Environmental temperature 2. Relative humidity3. Composition of the diet4. Growth rate

Cont. …

Meat birds drink at least twice as much water as the amount of feed consumed on a weight basis.

Cont. …

Actual water consumption relative to feed intake varies depending on environmental temperature and dietary factors. – Increasing dietary crude protein increases water intake and water :

feed ratios (Marks and Pesti, 1984) – Crumbled or pelleted feed increases both water and feed intake

relative to mash diets, but water: feed ratios stay relatively the same (Marks and Pesti, 1984)

– Increasing dietary salt and other osmotically active Minerals increase water intake (Marks, 1987)

7- Health Status of Birds/Diseases

Healthy birds --------- Normal feed consumption Sick birds ---------------feed consumption will be less

8- Ambient Temperature

Poultry have increased energy requirements to maintain normal body temperature in cold ambient temperatures and the opposite in hot ambient temperatures.

The process of digesting food produces body heat, and the amount of heat produced will vary according to the nutrient composition of the diet. This is called the heat increment of the diet.

Cont. …

In cold temperatures it may be desirable to formulate a diet with a higher heat increment and the opposite in hot temperatures.

9- Stress

Stress has adverse effects on reduced feed intake. Elevation of the stress mounting an immune response is

compromised by hormones associated with the stress response causes reduced absorption of specific nutrients.

Cont…

Nutrient absorption and gut motility reduced substantially during the stress response .

Acute stress may cause a momentary decrease in feed intake with minimal impact on performance.

Cont..

Chronic stress will have a marked and persistently detrimental effect on nutrient absorption and utilization.

Chronic stress can be influenced by three environmental stressors: 1. Heat stress.2. Poor air quality.3. Poor litter quality.

10- Heat Stress

Heat is removed from the body by insensible heat loss . The degree of heat stress endured by a bird is dependent

upon several factors, including1. Body size 2. Growth rate 3. Ambient temperature 4. Amount of convective heat loss influenced by air speed

11- Poor Air Quality

Adequate ventilation reduces air moisture, dust, ammonia, and carbon dioxide and brings in more oxygen.

High air moisture – Decreases evaporative cooling and thus adversely affects feed intake

in sensitive heat load. Excess air dust – Causes Inflammation of the respiratory system, which depresses feed

intake.

Cont..

Excess ammonia– Not only irritates pulmonary tissues, but it also is a metabolic stressor

that causes depressed feed intake. High levels of carbon dioxide or low oxygen levels in the air – Results in depressed metabolic rate that ultimately causes depressed

feed intake.

12- Poor Litter Quality

Poor litter quality is also a medium of many of pathogens that challenge the health status of the flock.

13- Fiber Content Of The Feed

Presence of large quantity of higher polysaccharides like cellulose and lignin in chicken diet increases bulk in feed.

Lignin and Cellulose cannot be digested by chicken. The efforts to convert the polysaccharides in to mono or

disaccharides will result in tremendous increase in food energy for chicken.