Poultry Flashcards
Why is the poultry industry so important?
- Wide variety of species and systems
- Over 90 million broiler chicks placed in the UK and nearly 90 million broiler chickens slaughtered per month.
- 140,000 tonnes of chicken meat per month.
- 2.4 million commercial laying hen chicks placed in the UK. (Lot less as they have a longer lifespan than broiler chicks).
- 11.3 billion eggs produced in the UK in 2021
Why is the poultry industry important to vets?
- Commercial companies are very large and tend to have their own vets.
- But independent farms, particularly free range laying eggs, may use independent vets.
- Birds are rarely treated individually.
- Backyard poultry and very common and you are likely to come across them in practice.
- Individual birds are more visible.
- Important safety impacts with relate to the production system are food safety, disease control and environmental impact.
Why is the poultry industry unique?
- Contains the most intensively housed livestock in agriculture – the first animal based agri-business.
- Most highly mechanised.
- Requires high level of financial capital.
- Labour requirements are low.
- Individual bird performance has increased year on year bringing down the relative unit cost.
- Chickens are efficient converters of feed, but feed is most important unit cost.
Briefly describe broiler chicken production.
- Slaughtered around 5/6 weeks old
- Mostly loose housed, indoor barn
- Often white birds, with very large breasts and legs
Briefly describe laying hen production.
- Slaughtered 80-100 weeks old
- Mostly free range, with some barn and cage
- Mostly brown with a few white laying flocks in the UK
- Not as substantial build
What are the life stages of laying hens?
- Males and females grandparent flock
- Eggs
- Males and females breeding flock
- Eggs
- Day old chicks – a pullet
- Become the female only laying flock
- Produce eggs for sale
What are the life stages of broiler chickens?
- Male and female grandparent flock
- Eggs
- Male and female breeding flock
- Eggs
- Chicks
- Male and female table birds at 5-6 weeks
What are the life stages of turkeys?
- Male and female breeding flock
- Eggs
- Poults – day old chicks
- Chicks
- Male and female table birds at 18-20 weeks
What are the life stages of ducks?
- Male and female breeding flock
- Eggs
- Chicks
- Male and female table birds at 42-56 days old
Describe the laying hen market.
Major egg packers control the market and have developed brands. Mixture of contract production and company owned farms. Pullet rearing separate.
Describe the broiler chicken market.
Processors control the market. Nearly all contract production. Lots of further processing.
Describe the turkey market.
2 large integrators control the intensive market. Significant traditionally produced Christmas market. Lots of further processing.
Describe the duck market.
2 large integrated companies produce meat, 3 produce eggs.
Describe the laying hen breeding pyramid.
- 6 genetics companies
- Each with their own lines for different markets, for example, colonoy vs free range, white eggs vs brown eggs.
- 3 breeds of layer dominate the UK market – Hyline. Lohmann and Novogen
Describe the broiler chicken pyramid.
- 4 genetic companies
- Each with their own lines
- 2 breeds of broiler dominate the UK market – Ross (Aviagen) and Cobb (Cobb breeding company)
Describe laying hens furnished cage systems.
29%
- Stocking density: 750cm2 per hen (~13 birds/m2), 600 cm2 must be usable are (45cm high)
- Group size: 60-80 birds per cage
- Facilities: perch, nest box, scratch mat
- Access to outdoors: no
Describe laying hen barn systems.
- Stocking density: 9 birds per metre squared usable area
- Group size: 32,000 birds (RSPCA)
- Facilities: 1 m2 nest space per 120 birds, litter
material to dustbathe and forage in, perches - Access to outdoors: no
- Other information: some systems multi-tier/aviary, providing additional levels to use above the ground
Describe laying hen free range systems.
- Stocking density: 9 birds/m2 usable area
- Group size:16,000 birds (RSPCA)
- Facilities:1 m2 nest space per 120 birds, litter material to dustbathe and forage in,15 cm perch space per bird
- Access to outdoors: yes (from 21
weeks (RSPCA), adequate outside area, appropriate for the size of the flock (size
of the popholes: 2m per 1000 birds). - Other information: some systems multi-tier/aviary, providing additional levels to use above the ground
Describe laying hen organic systems.
- Stocking density: 6 birds/m2 usable area
- Group size: 2000 (Soil association), 3000 EU legislation
- Facilities: 120 cm2 per bird in a communal nest, 18 cm perch per bird, 50% of floor area solid covered with litter
- Access to outdoors: yes, from 12 weeks, 1000 birds per ha
Describe standard indoor broiler chicken systems.
- Large, closed buildings
- Temperature, artificial lighting, ventilation, food and water carefully controlled
- 25,000-50,000 birds
- Variable stocking density, depending on management on farm
Describe improved indoor broiler chicken systems.
- Natural daylight through windows
- Reduced sticking densities environmental enrichment, such as straw bales
Describe broiler chicken free range systems.
5%
Access to an additional outdoor range area for part of their lives via popholes in the side of the building
Describe broiler chicken organic systems.
- Must have access to range 2/3 of life
- Suggest use of enrichments like perches inside the house
Describe turkey standard indoor systems.
95%
- Reared on the floor of large, purpose built sheds or converted farm buildings
- Up to 25,000 birds may be housed in one building
Describe turkey pole barn systems.
Upper part of the house walls are open, allowing natural light and air
Describe turkey free range systems.
5%
Similar to indoor or pole barn systems but eth turkeys also have access to an outdoor range area
What are the stocking densities of laying hen systems in birds/m2?
Enriched cage = 13
Barn = 9
Free range (indoor) = 9
Free range (outdoor) =1
Organic (e.g. soil association) = 6
What are the stocking densities of broiler chicken systems?
Standard = 13-15 (33-39 kg/m2, assuming adult bird weighs approx. 2.5kg)
Improved indoor = 12 (RSPCA – 30 kg/m2)
Free range (indoor) = 11 (RSPCA – 27.5 kg/m2)
Free range (outdoor) = 1
Organic (e.g. soil association) = Fixed housing: 8 (21 kg/m2); mobile housing:12 (30 kg/m2)
Describe geese.
Mainly derived from the greylag goose/Anser anser but also from Anser cynoides may be kept.
- Annual moult
- Fully webbed front feet
- Tend to fee don land and eat forage
- Males and females tend to be the same colour
Describe ducks.
Domesticated ducks are derived from the wild mallard and the Muscovy duck.
- Moult twice
- Dimorphic plumage – multi-coloured with difference between the sexes
- Tend to feed on water
Describe indoor housing systems for ducks.
- Typically several thousand birds reared on the floor of a large building/barn
- Should have access to a water trough big enough to dunk their heads
Describe free range housing systems for ducks.
- Similar to indoor, but with access to an outdoor range area
- 2500 ducklings per hectare
Why is lighting important for poultry?
- Important for all poultry
- Extended day lengths to bring birds into lay
- Low light levels and dawn and dusk dimming to keep birds calm
What are the dark hours of day needed for poultry?
Broilers = 6 hours
Laying hens = 8 hours
Turkeys = 8 hours
What are the effects of intermittent and natural daylight on poultry?
To mimic natural rearing environment – intermittent lighting and dark brooders.
Natural daylight as they can see much more in the lower end of the wavelength spectrum and can detect up to 90-100 Hz of light flickering. So artificial light may affect behaviour.
What are the weights of laying and broiler chickens, ducks, geese and turkeys?
Lay hens = 1.9kg
Broiler hens = 2.3kg
Duck = male 5kg, female 3kg
Goose = 4.5kg
Turkey = female 7kg, male 10(-18)kg
When are broilers, ducks, geese and turkeys slaughtered?
Broilers = 32-40 days
Duck = male 84 days, female 68 days
Goose = 70 days
Turkey = female 110 days, male 130 days
What are the factors affecting the performance of poultry?
- Genetics
- Nutrition
- Sex
- Age
- Water quality and availability
- Temperature
- Environmental pollution, such as ammonia
- Stockmanship, such as management and use of enrichments
- Stocking density: indirectly through effects on the above
- Disease and welfare
What is the house temperature for laying and broiler chickens?
Laying = 17-25˚C depending on system of production
Broiler = not more than 3˚C above the outside temperature when the outside temperature exceeds 30˚C.
What is the humidity of laying and broiler chickens?
Laying = 40-60%, up to 70-75% for short periods
Broiler = must not exceed 70% when the outside temperature is below 10˚C
What is the light intensity in laying and broiler chicken housing?
Laying = at least 10 lux. Nest boxes less than 1 lux
Broiler = at least 20 lux. Photoperiod: at least 6 hours of dark each day, 4 of which must be continuous
What is the ammonia concentration in laying and broiler chicken houses?
Less than 20 ppm
What is the carbon dioxide concentration in laying and broiler chicken housing?
Less than 3000 ppm
Define thermal comfort zone.
Conditions in which a bird is likely to be able to maintain body temperature and not have to work excessively hard to do so by shivering (cold) or panting (hot).
Describe the anatomy of egg laying.
22-26 hours
1. Yolk released by the ovary
2. Enters the oviduct where fertilisation would take place
3. Albumen forms around the yolk in the oviduct
4. Held together by a thin membrane
5. Shell added by the shell gland in the uterus
6. Liad via the cloaca
Describe the characteristics of the eggs produced.
- Eggs for breeding – egg is an incubator for a chick for 21 days
- Eggs for eating are when the egg is not fertilised
- Pores in the eggs shell allow movement of water vapour and gas exchange
- The yolk is 33% lipid and 17% protein
- Albumen is 10% protein
What is beak trimming and the methods?
- Blunts the tip of the beak to make it less damaging
- It involves the removal of part (less than 33%) of the beak before chicks are 10 days old
- Methods: hot or cold blade, robotic, chemical, laser
- Welfare implications: acute and chronic pain, behaviour change
What are the issues of hot blade trimming?
- Possible formation of neurones
- Shorter beaks
- Scar tissue
What are the advantages of infrared trimming?
- No open wound
- Reduction in operator error
- Gradual change in beak shape
- Reduced stress
- Reduced feather pecking
- Improved feather conditions
- Improved feeding behaviour
What is the legislation on beak trimming?
Infrared method must be used and the tip of the beak falls off 10 days after treatment. There is a move to ban beak trimming, which is considered a mutilation.
What are the production and welfare concerns of broiler chickens?
- Rapid growth rate – heart defects and lameness
- Space allowance and facilities – performance of normal behaviour of mating, space and environmental enrichment
- Foot pad dermatitis/pododermatitis/hock burn
- Breeding flocks – mating injury and hunger
How is lameness assessed in poultry and the consequences of lameness?
Assessed by gait scoring
Lameness is painful and reduced production – birds may not be able to reach food, reducing growth and increasing mortality
What is the solution to lameness is heavy birds?
Heavy birds simply cannot hold their weight: broken limbs, rickets.
Solutions: breeding and keeping active by enrichments and perches
What is foot pad dermatitis/hock burn?
Lesions on the feet and legs. Possible caused by poor litter quality.
Use wood shavings, maintain dry litter for good drainage or litter replacement or appropriate ventilation to control humidity.
What is the consequence of high humidity?
Wet litter and increases heat stress as it makes it more difficult for birds to thermoregulate
What is the consequence of poor air quality?
Poultry houses are dusty. Total maximum 5.5 mg/m3 and 84.5 mg/m3
When is a substance classed as hazardous to health?
Defined as dust of any kind when present at a concentration in air ≥ 10 mg/m3 8-hour of inhalable dust (COSHH).
What is the consequence of dust and ammonia?
Ammonia levels are often high (particularly when litter is wet)
Combination of dust and ammonia: particularly prone to respiratory diseases, such as infectious bronchitis, mycoplasma, infectious Coryza
Why is ventilation important?
- Minimum ventilation must supply fresh air for oxygen and remove sufficient carbon dioxide, moisture and aerial pollutants.
- Rule-of-thumb, minimum ventilation for all classes of poultry is 2 m3 air per second per tonne of feed consumed daily.
What are the stages of red jungle fowl courtship behaviour?
- Feather ruffling
- Waltzing
- Crowing
- Tidbitting
- High step advance
- Wing-flapping
Why is feed restricted in broiler chickens?
Broilers are selected for fast growth and weight gain. This can lead to lameness, reduced reproductive performance, and high mortality. So, feed is restricted in order to achieve:
- Good reproductive performance
- Good health and low mortality of the female breeder
- Satisfactory growth of the offspring
What are the consequences of restricting broiler chicken feed?
Chronic hunger; contravenes five freedoms (freedom from hunger)