Egg Production Flashcards
Important anatomy of the egg
- chalazae holds yolk central (important w.r.t. Turning in incubation)
- air sac older the egg, larger the air sac
Classes of eggs
> class A - small air cell - very clean - no abnormalities >class B - odd shape or size - dirty - broken out and pasteurised before use > class C - industrial, NON FOOD - shampoos and soap
Can eggs be washed?
- no not in this country NO EGGS can be washed
- minimise risk of salmonella spread
What does the red Lion mean?
Flock always vax against salmonella
How are eggs pasteurised
- egg to be heated to 64.4* for 2.5mins
- destroys all pathogens without affecting any good qualities of the egg
- egg cooled to below 4* then packed
How does egg colour reflect welfare?
- brown eggs from brown hens pdf cannabilism
- White hens not (in US use these)
- in UK beak trimming needed
Food safety risks
- campylobacter broilers
- salmonella layers
> salmonella enteritidis, salmonella typhimurium
> rod g- bacterium (enterobacteriaceacae) - transmitted by rodents and wild birds
Pathogenesis salmonella
- feacal oral
- can be via URT
- conjunctiva maybe
- colonisation of digestive tract and invades and multiplies in enterocytes and tonsillar lymphoid tissue
- attachment through fimbrial appendages (abx = fimbrial blockers)
- gut damage and diarrhoea
Are there salmonella control programmes?
2 national control programmes
- layer
- broiler
Outline salmonella control in broilers
- samples taken at chick placement
- samples taken within 3w birds being sent for (slaughter?? missing from lie)
Salmonella control in laying flocks
- test as day old
- test within 2 w of lay/before transfer to laying farm
- test q15w (first test within 22w)
Campylobacter
> c. Jejuni
- campylobacter g- thermophilic, obligate microaerophilic bacterium
- ubiquitous in temperate environments
- likes birds d/t ^ core body temperature
Pathogenesis of campylobacter and interventions to v ?
- colonises mucus overlying epithelial GIT cells
- multiple intervention strategies
- each time a carcasse tx to remove or destroy campy (physcial/chemical not UK) numbers will be reduced
1* production interventions to reduce campy
- investigate biosecurity
- hygiene barriers, fly screens, water Tx
- review rapid on-farm campy test
- investigate motivational drivers of biosecurity compliance (£££)
Transport interventions
> Esp at thinning
- crate washing and drying
- novel crate and disinfection methods
Processing intervention
- lactic acid wash turkey and chicken
- new water spray
- sonar and steam
- rapid chilling
Retailer intervention
- leak proof packages
- consumer education
- investigate impact of modified atmosphere packing
- consumer attitude and behaviour
- on-pack best practice preparation and cooking etc.
Catering interventions
- undercooked liver pate and parfait
- best practice toolkit
What makes up an egg
- water, fat and protein
