Poultry Nutrition

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Poultry Nutrition
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Contents

• Digestive System
• - Structure of digestive tract
• - Functions of digestive tract
• Nutrition requirements of poultry
• Energy, protein, vitamins minerals
• Importance of water
• Feed intake factors
• -Feed form - pellet v/s mash
• Diet formulation
• - Rations for broilers
• - rations for layers
• Odds n ends
• Welfare codes

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• Feed accounts for over 70 of the cost of
  producing poultry meat and over 60 of egg
  production costs.
• The poultry digestive system is relatively simple
  and short, but extremely efficient.

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Food Conversion

• Poultry are extremely efficient feed converters
• There have been huge advances made through
  selective breeding
• Example
• - Broiler food conversion is 1.7 (it takes
  1.7kgs of feed to put on 1kg of body weight gain)

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Structure of digestive tract
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Structure of digestive tract
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Digestion

• Digestion - The process of breaking down complex
  nutrients into a simpler organic compounds, so
  they can pass through the membrane of the gut
  into the blood (absorption).
• The digestive tract is the tube which extends
  from the mouth to the cloaca / anus and is lined
  with mucus membrane.
• Process in digestion may be grouped as
  mechanical, chemical and microbial.

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Digestion in Poultry

• Poultry have a monogastric digestive system
• In poultry the digestive tract differs from
  mammals in a number of ways.
• In poultry the lips and the cheeks are replaced
  by the beak and teeth are absent (do have tongue)
  but no chewing of food.
• Food is coated with saliva in the mouth and
  passes down the oesophagus.

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Sustainable food

• Poultry meat is the most environmentally
  efficient of all meat proteins
• Improvements in poultry production yields and
  efficiency have resulted in major environmental
  benefits and reduced some land use change impacts
• Poultry meat consumption contributes just 1 of
  total UK greenhouse gas emissions
• Soybean meal is the most nutritionally and
  environmentally efficient protein crop for
  inclusion in poultry feed and other livestock
  feeds globally.

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• Crop
• - a diversion of the oesophagus
• - pear- shaped sack
• - function to store food
• - filled and emptied by peristalsis
• - Food can by-pass the crop when lower parts of
  the digestive tract are empty
• Salivary amylase continues to act on starch
• Mainly lactobacilli adhere to the crop wall
  microbial fermentation products are lactic and
  acetic acids

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• Proventriculus or glandular stomach
• produces hydrochloric acid and pepsinogen
  (enzymes)
• Minimal own movement so food passes through
  quickly by oesophageal contractions
• Gizzard
• Muscular organ, with internal ridges, and a hard
  internal surface
• Rhythmic contractions to grind food with moisture
  into a smooth paste (i.e. mechanical digestion)
• Presence of grit in the gizzard (although not
  essential) has been shown to increase the
  breakdown of whole grains by 10
• Proteolysis occurs in the gizzard
• Thus the proventriculus and gizzard are
  equivalent in function to the mammalian stomach

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• When ground sufficiently small, digest-a pass
  into small intestine
• Reflux between gizzard and intestine can occur
• Pancreatic juice containing enzymes and bile
  flows into the small intestine (for digestion of
  proteins, fats and carbohydrates)
• The small intestine is where most of the
  breakdown of food occurs and the nutrients are
  absorbed (major absorptive site is at the
  jejunum)
• Surface specially adapted for absorption by
  folding and the presence of villi

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• Caeca
• 2 long blind sacs where the small intestine joins
  the large intestine
• Function as absorptive organs
• Not essential organs (as surgical removal causes
  no harmful effects)
• Cellulose-digesting bacteria on surface mix with
  digest-a by peristalsis, this leads to
  fermentation, with the production of volatile
  fatty acids (VFAs)
• Experiments with poultry have shown that
  cellulose in cereal grains is not broken down by
  microbial activity to a great extent (so it is
  unlikely that the VFAs contribute much to
  satisfying the energy requirements of poultry)

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• The ceaca are emptied by peristalsis into the
  relatively short colon (or large intestine)
• Main function of the colon is to transport
  digest-a to its termination at the cloaca
• Faeces and urine are excreted together from the
  cloaca
• the cloaca combines the function of the rectum
  and bladder
• Overall passage of food through the digestive
  system ranges from 2-24 hours
• It is fastest in growing and laying chickens

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Nutrient Requirements of Poultry
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Nutrient Requirements of Poultry INTRODUCTION

• Housed livestock are entirely dependent on their
  compound feed containing the correct amounts
  proportions of nutrients
• They have no access to herbage or soil, or
  sunlight

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Nutrient Requirements of PoultryENERGY

• Energy is assessed using the Metabolisable
  Energy (ME) system
• Energy is first used for maintenance of normal
  body functions
• Amounts above this are used for production, i.e.
  eggs or growth
• Excessive energy supply leads to undesirable fat
  deposition
• ME content of rations generally in the range
  11-13 MJ/ME/kg

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Nutrient Requirements of PoultryPROTEIN

• Protein is required for body development in
  growing birds, and a good proportion is also
  required by layers as eggs contain 13-14
  protein
• Protein Quality
• 2 most important amino acids are lysine
  methionine (LM).
• Cereals (wheat, maize) are a poor source of the
  correct amino acids
• Soya bean is the best vegetable protein source
  (although poor for meth, so cannot be used as the
  only source)
• Animal protein (fishmeal) is the richest source
  of LM
• Synthetic amino acids are added to feeds to
  improve protein quality
• Sunflower meal is high in methionine (but high
  fibre content limits its use)

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Nutrient Requirements of Poultry VITAMINS

• Sources of vitamins may be naturally occurring,
  or synthetic forms

Vitamin Function Source
A Growth, resistance to disease Green veg, maize, fish liver oil, synthetic
D (in the form of D3 ) Utilises Ca P properly vital for bone and egg shell Sunlight, fish liver oil, synthetic
E Deficiency affects nervous system, also for hatching eggs Cereals, Will be destroyed by bad storage or overheating
K Blood clotting (deficiency haemorrhaging Green foods, Lucerne meal, synthetic
B group (incl. Biotin, Choline folic Acid) Optimum growth, metabolism of carbohydrates, feathering, hatchability, red blood cells, biotin prevents fatty liver syndrome. Cereals, synthetic
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Nutrient Requirements of PoultryMINERALS

• Calcium and phosphorus
• Necessary for bone formation (assoc. with leg
  weakness) and egg shell
• Calcium to phosphorus ratio should be 21
• Animal derivatives are the richest in calcium
  when compared to plant sources, although all
  foods have some calcium content
• Phosphorus in cereals may be in a form that is
  poorly absorbed, so supplements may be needed
• Absorption of Ca P requires vitamin D3 and
  manganese
• Di-calcium phosphate or fishmeal can be added to
  the diet as an extra source

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Nutrient Requirements of PoultryMINERALS
MINERAL FUNCTIONS
Manganese Involved with calcium metabolism Good hatchability of eggs Shell strength To promote bone formation Source Wheat, Limestone and manganese sulphate
Iron, Copper and Cobalt Essential for formation of haemoglobin
Iodine Associated with poor hatchability Source usual feeds but especially fishmeal
Common salt (sodium chloride) Essential for protein digestion Excess salt causes thirst and wet droppings (max 0.5 in diet) Excess or deficiency seriously affects productivity (both growth and egg production).
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• Calculation of Nutrient Requirements
• Energy
• Amino acids
• SEE HANDOUTS FOR CALCULATIONS

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Water

• Access to fresh clean water at all times is
  absolutely essential in intensive livestock
  production systems
• poultry must have a constant water supply to
  maintain efficient production
• Young chicks or birds in hot weather can die in
  only a few hours if water is absent
• Water consumption of the flock should be
  monitored and recorded daily
• A change in water consumption is a crucial early
  indicator of a health problem, or heat stress

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Approx. Daily water consumption

• Water consumption increases with bodyweight (i.e.
  age)
• SEE HANDOUT - TABLE OF BROILER WATER CONSUMPTION

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Drinker Management

• Check position and height of drinkers
• Check drinkers for water daily (nipple drinkers
  can be dry
• without you noticing)
• Leaky drinkers create wet litter management
  problem
• Protect pipes from freezing
• Clean and disinfect water
• equipment between crops

Nipple drinker
Bell drinker
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Feed Enzymes

• Incorporated into poultry diets for the following
  reasons
• Enzymes act on cereal proteins within the birds
  digestive tract, complementing the birds own
  digestive enzymes
• Safe, non-toxic to man, no harmful residues
• Granular or liquid forms
• Granular can be included in vitamin/mineral
  premix
• Heat conditioning during pelleting damages
  enzymes, so must be added afterwards
• Benefits efficiency of feed utilisation
• Can partially act as a replacement for antibiotic
  growth enhancers (all are now banned in EU since
  Jan 2006)

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Factors affecting feed intake

• The energy concentration of the ration is an
  important characteristic, because if it is
  increased/decreased poultry will tend to adjust
  their intakes to provide a constant energy
  intake.
• Appetite is influenced by contractions of an
  empty crop (physical receptors)
• Layers have a specific appetite for calcium
• Poultry seem to have the ability to select for a
  balanced diet (i.e. meet their energy and protein
  requirements) when offered a range of feeds
• Learn food preferences from previous experiences

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Factors affecting feed intake

• Physical form of food Pellet v mash, fine
  particles in the feed
• Environment temperature, humidity, ventilation,
  light
• Equipment
• feed space per bird,
• trough position - base height level with birds
  back (reduces spillage)

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Feed equipment

• Type of feeder
• Pan feeder
• Chain feeder (trough type)
• Look up suppliers of poultry
• equipment
• www.bigdutchman.com
• www.vencomatic.com

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Practical Feeding

• Layers and broilers generally fed ad-lib
• Broilers generally fed starter, grower
  finisher rations
• However, broiler breeders are restricted on low
  energy and protein diets, to control bodyweight
  (as fast growth is undesirable)
• Broilers fed crumbs (smaller pellets) for chicks,
  then pellets. Layers usually fed mash (coarse
  ground grains)
• Poultry rations are complex so few farms mix
  their own diets, and also the competitiveness of
  feed companies ensures lowest possible cost.
• Farms must follow the detailed programme
  suggested by the breeding companies for their own
  strain of birds

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Feeding

• SEE HANDOUTS nutrient requirements
• Note in poultry diets there must be a correct
  ratio between metabolisable energy (kcal/kg) and
  crude protein of the diet, which varies depending
  on age or type of bird
• 1 MJ 240 kcal (kilo-calorie), and 1 kcal
  1000 calories

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Diet Formulation

• Necessary to have all info so far up to date
  costs of ingredients
• A diet has to be formulated that is
• of minimal (or, at least, favourable) cost
• satisfies all the nutrient standards given
• Stays between the min max inclusion rates for
  any ingredients
• Represents uniform content throughout batches

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Diet Formulation

• Because the possible range of ingredients is so
  large, an enormous number of calculations are
  involved in working out all the options
• Feed companies will use computer software to do
  this efficiently and quickly!!!

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A few notes on diets

• Cereals usually make up 50-75 of a poultry diet
• Cereals supply a high proportion of starch (the
  lowest cost form of dietary energy)
• Cereals may supply up to 50 of the protein
  required, however the quality is poorer
  (deficient in essential amino acids), so oilseed
  meals (e.g. soya-bean 50CP) and fishmeal are
  used as protein concentrates
• Max inclusion rate for fat (source of energy) is
  6
• Above this level feed is sticky (machinery cant
  work with it) and it can be difficult to form
  hard pellets

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Feeding plan Layers
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Feeding plan Broilers
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Grain Balancer Rations

• A technique that can be used for poultry is the
  addition of whole wheat to the diet
• e.g. Broilers
• when fed at up to 30 of diet it costs 3.5p less
  to rear a broiler to 49 days, with no loss of
  feed efficiency
• makes a cheaper ration, can be scattered on floor
  to occupy the birds, but need separate storage
  bin

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Mycotoxins as contaminants of feed

• Mycotoxins are the toxic metabolites of fungi
• Over 200 types are known
• Responsible for significant financial loss to the
  poultry industry
• decreased growth rate, food conversion
  efficiency, livability, reproductive potential
• Feed importers may test deliveries for presence
  of mould, silos should be cleaned regularly
• Feed additive look up www.alltech.com
  Mycosorb

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Welfare Codes

• Feed Water Provision
• SEE HANDOUT

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• The condition of the droppings is a good guide to
  state of health

Wet droppings Nutritional abnormality or general infection
Green droppings Liver (bile) disorder
White droppings Kidney infection
Red droppings Indicate presence of blood may be due to coccidiosis or an acute bacterial infection
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Conclusions

• You just never know when these lecture notes may
  come in handy... livestock feed companies and
  nutrition companies are a major employer of Ag
  graduates.

Total deliveries of feed compound and other processed animal feedstuffs by NI feedstuffs manufacturers in 2012 Total deliveries (in Thousand Tonnes)
All cattle (beef, dairy and calves) 1190.6
Poultry 692.8
Pig 165.4
Sheep 75
NI Animal Feed Statistics 2012, DARD