Poultry Husbandry Egg production systems

History of the laying hen Wild junglefowl – approx 60 eggs/year 1960’s – commercial egg laying breed produced approx 200 eggs/year Now approx 320 eggs/year

Egg Production Systems

Cleaning and Disinfection of Poultry Houses Cleaning and Disinfection of Poultry Houses  Insect Control  Operations prior to cleaning –Water tank, pipes and nipples –Clean and de-scale –Rinse twice with clean water –All the equipment – nests feeders drinkers –Entire Ventilation system –Litter removed

Washing  Washed, disinfected  Rodent control  Assessing disinfection effectiveness –Visual exam –Bacteriological –Resting Period

Good Brooding Conditions  Day old to POL (point of lay) is critical time. –Success in rearing house – success in the laying house –E.g. delay in growth at 4-5wks will reflect in bodyweight at 16 weeks and then in mean performance – e.g mean egg weight

Temperature and Humidity  Raise house temp to 28-31°C –Heat losses incurred from contact with the litter very important in first few days –2 gas brooders or 2 radiant heaters advised for 1000 birds –Temperature and relative humidity should be uniform throughout the building

Feeding Technique  The feeding techniques between weeks are designed to: –Avoid the build up of the fine particle residues –Rapid feed intake –Feeding times and rapid intake

Targets in rearing  To produce a uniform flock and a weight which is compatible with the intended age at sexual maturity  To obtain the correct weight at 4 weeks to secure frame development  To achieve steady growth between 4 and 16 weeks with a good development of the digestive tract

General principles of lighting programmes during rearing  Chickens are sensitive to changes in duration of light:- –it will influence the age of sexual maturity –It will influence feed consumption

Lighting Programme and Growth  In addition to the influence of growth light will effect:- –Progressive growth of the digestive system –Gradual adaption to a body clock (e.g. anticipation of a dark period) –Lack of night time energy supply when dark periods are too long

Table Egg Production Systems The Laying Phase weeks

Welfare – the 5 freedoms What ‘natural behaviours’ do hens exhibit in the wild? Foraging for food by exploratory pecking and scratching over distances Preening and dust bathing Use trees for roosting at night (perches) Seek out a secluded spot for laying and build a nest Congregate in small groups with a complex social order (hierarchy)

Behaviours include: Dust bathingPerchingInvestigationNesting Comfort and grooming behaviours All laying birds still have strong desire to display normal behaviours:

Welfare of Animals Act (Northern Ireland) 2011 Welfare of Farmed Animals Regulations (Northern Ireland) 2012 Legislation

Caged Production

Welfare Regulations for hens in Conventional Cages  From 1 Jan at least 550sq.cm. cage area per hen (previously 450 sq.cm)  Cages are fitted with claw-shortening devices  From 1 Jan 2003 no such cages may be built or brought into service  Existing cage systems prohibited from 1 Jan 2012  Minimum requirements for feed space,water space, cage height and slope of floor are specified See DARD regulation document or welfare code of practice

DEVELOPMENTS WITH CAGES – The ‘Enriched’ cage is the only cage system option permitted from 2012 Increase area / hen – 750 cm 2 Provide perching spaces – 15cm per hen Provide nest boxes in each cage Provide litter (dust bath) in each cage Abrasive strip to control growth of claws (“a claw- shortening device”) Thicker wire in floors ( wire of standard floors damages feet) See DARD regulation document or welfare code of practice for spec

Enriched vs. Conventional cages EnrichedConventional Minimum space Nest Litter Perches Trough Height Inspection 550 cm2 per hen Total = 2000 cm2 750 cm2 per hen (600cm2 + nest box) X X 90 cm between tiers 35cm from floor to bottom tier 35 to 40cm 45cm (20cm nest box) 10cm per hen 12cm per hen 15cm per hen X

Egg production performance (cages)  Laying cycle – 16 to 74 weeks of age  Egg output – 335 eggs per bird  Mortality – 4%  Feed intake grams per bird per day  Downgrades – 8%

LAYING PHASE- Egg production in cages Advantages of cages for egg production Increased no of eggs harvested compared to deep litter or free range Increased no of eggs harvested compared to deep litter or free range Reduced food consumption as high stocking density allows high temperatures to be maintained Reduced food consumption as high stocking density allows high temperatures to be maintained reduced labour - easy to mechanise feeding, cleaning and egg removal reduced labour - easy to mechanise feeding, cleaning and egg removal Cleaner eggs - soiled eggs get a lower price Cleaner eggs - soiled eggs get a lower price Lower mortality - less cannibalism, lower levels of disease, no mortality from foxes Lower mortality - less cannibalism, lower levels of disease, no mortality from foxes

Better control of intestinal parasites No litter costs No litter costs Higher stocking density - lower capital costs Higher stocking density - lower capital costs Ease of management of stock Ease of management of stock No contact with wild fowl or rodents - lower risk of salmonella, Gumboro disease, Newcastle disease & Avian Flu. No contact with wild fowl or rodents - lower risk of salmonella, Gumboro disease, Newcastle disease & Avian Flu. BUT Confined environment Not natural for bird Not natural for bird Laying cages have been clear focal point of anti-intensive farming lobby Welfare advantages

Sudden drop in food intake indicates a problem Compare egg production with standard graph Compare egg production with standard graph Is egg size on target Is egg size on target Monitor downgrades Monitor downgrades Limit food wastage Limit food wastage Record mortality Record mortality Management points

Alternative systems of egg Production Definition: Alternative systems means alternatives to cages for lying hens. The alternative systems are sometimes called colony systems as the total flock of hens is kept in one large colony

Tiered / Barn

Tier system - Barn System Achieves a high stocking density by using the vertical space in a building while improving bird welfare in comparison to cages Commercial tiers are three tiers highCommercial tiers are three tiers high Perches and nest boxes are providedPerches and nest boxes are provided Provision of litter for 1/3 of floor areaProvision of litter for 1/3 of floor area

Egg production performance (Tier/Barn)  Laying cycle – 16 to 74 weeks of age  Egg output – 325 eggs per bird  Mortality – 6%  Feed intake grams per bird per day  Downgrades – 10-12%

Welfare advantages Freedom of movement Freedom to stretch wings Freedom to stretch wings Nest boxes provided for Nest boxes provided for egg laying egg laying Perches provided 15cm/hen) Perches provided 15cm/hen) Freedom to dust bathe if Freedom to dust bathe if litter provided litter provided

Welfare Better than in cagesBetter than in cages Hens travel greater distancesHens travel greater distances Leg bones strongerLeg bones stronger NestingNesting PerchingPerching Freedom to stretch wings / fly short distancesFreedom to stretch wings / fly short distances

Disadvantages in Comparison with cages Floor laid eggs on litter and slats - high labour Fewer eggs harvested - approx 7 eggs/hen/yr lost Fewer eggs harvested - approx 7 eggs/hen/yr lost More difficult to mechanise egg collection More difficult to mechanise egg collection Hygiene of eggs poorer i.e. more soiled eggs because laid in nest -- downgraded Hygiene of eggs poorer i.e. more soiled eggs because laid in nest -- downgraded Extra energy cost of activity - slightly higher feed intakes Extra energy cost of activity - slightly higher feed intakes Higher capital costs Higher capital costs

Tier system - get a lot of aggression and feather pecking due to unstable social order. Beak trimming may be necessary Hens in tiers were found to be less aggressive than caged hens - but hens in group pens without a perch were more aggressive than caged hens

Free Range

Free range  Protection from: –Adverse weather conditions –Predators –Risks to health  Access to: –A well-drained lying area at all times.

Egg production performance (free-range)  Production cycle – 16 – 74 weeks of age  Egg output – 325 per bird  Mortality – 6-10%  Feed intake – 125 grams per bird per day  Downgrades – 12%

Free range systems House interior can be in deep litter or tiered If no litter in house can still dust bathe outside - but only where soil is dry enough Welfarist’s regard free range as the ideal in comparison with other options. Free range eggs are perceived to have a healthy eating image in the mind of the consumer

Welfare Advantages As for tiered or deep litter - only also access to pasture Welfare Disadvantages Lack of control of environmental temp - exposure to low temperatures - high feed intakes Lost eggs lower egg production - due to low temperatures high labour costs

Parasitic diseases Contact with wildfowl and rodents Predators can give high mortality Requires land Lot of aggression and feather pecking high cost of eggs Most difficult to control length of day in the lighting programme

Pop holes  Pop holes must be - –Along the entire length of the building –35 cm high and 40 cm wide (at least) –2 m total per group of 1,000 hens (at least)

Example of a poorly managed range

First Poultry Jungle Fowl

Breeding Objectives  Breeding programmes are based on maintaining separate pure lines “grandparent stock” (generally of the same breed), and then crossing them in a controlled manner to produce hybrid offspring. Selection for improved performance is carried out continuously within the pure lines.  Traits such as egg weight, egg numbers and feed efficiency are assessed. Also: shell colour & shell strength, resistance to disease.  Commercial breeding company example

Breeder Lines (4 yrs)  Pure Lines (genetic improvement /pure lines (thousands)  GGP (Great grandparent stock) (tens of thousands)  GP (Grandparent stock) ( )  Parent Stock ( )  Broilers  Processing ( )  Consumer ( tonnes) Source, McKay 2008

Breeding objectives eggs  Commercial layer- Objectives  To improve: - Bone strength - Egg numbers - Reduced skeletal defects - Peak for longer - Better egg quality later in cycle - Improved body conformation - Improved skeletal durability - Reproductive defects, in terms of diseases, prolapse and double yokers - More disease resistance- (EDS Egg drop syndrome)

Table egg Production  Breeds –White Leghorn (Italian origin) –Rhode Island Red (USA) –Light Sussex (England)

White Leghorn

Rhode Island Red

Light Sussex

Sources of further information  (Farm animal welfare council, makes recommendations for government to consider when writing legislation)         – NI Code of recommendations for the welfare of laying hens can be downloaded online