Egg Hygiene Flashcards
What are the top 4 producers of eggs?
- China
- India
- Indonesia
- USA
Where does egg formation begin?
ovaries - begins as a yolk by the rapture of follicles to release
What are the 5 places in the female reproductive system that develops the egg?
- infundibulum - yolk, sperm fertilization
- magnum - albumin
- isthmus - shell membrane, shape determined
- uterus (shell gland) - albumin, shell, cuticle pigment
- vagina/cloaca - egg is laid (egg has pores and can be contaminated)
When are hens able to lay eggs? How long does this take?
4-5 months
25 hours - lays an egg every 25 hours from 4-5 months to 18 months
What are the 3 major structures of eggs and their proportion?
- shell - 11%
- albumin (egg white) - 58%
- yolk - 31%
What makes up the egg shell? Why are eggs prone to contamination if they have a shell?
calcium carbonate
has small pores —> Salmonella commonly makes it through
What is the shell membrane? Air cell? Chalazae?
membrane that covers the albumen
formed by contraction of the contents of the egg during cooling and loss of moisture (not present in freshly laid eggs)
twisted cords that keep the yolk suspended in the albumin at the center of the egg
What is the vitelline membrane? Germinal disc?
membrane encapsulating yolk
part of the yolk where fertilization takes place
What is yolk rich in? Why?
high cholesterol = concentrated food for embryo if egg is fertilized
What are the major chemical compositions of eggs? Which are especially high in shells, albumen, and yolk?
- water = 77%
- protein = 12%
- lipids = 10%
- carbohydrates = 1%
SHELLS = minerals
ALBUMEN = protein (fat-free)
YOLK = lipid (fat)
What are the 2 major sources of egg contamination?
- microbes in reproductive tract before the shell forms around the yolk and albumen (vertical transmission) - Mycoplasma, Salmonella pullorum
- bacteria on the shell due to cloacal opening - enteric bacteria and viruses (Salmonella)
What bacteria are the most common bacterial pathogens affecting eggs?
- Salmonella***
- Mycoplasma
- E. coli*
- Chlamydia*
- Campylobacter*
- Coryza
- Ornithobacterium
- Gallibacterium
- Spirochets
What viruses are the most common viral pathogens affecting eggs?
- Infectious Bronchitis virus
- Avian Influenza virus
- Newcastle Disease virus
What syndromes commonly result from egg contamination?
- egg drop syndrome
- swollen head syndrome
- avian encephalomyelitis
- laryngotracheitis
- fatty liver hemorrhagic syndrome
- cage layer osteoporosis
What are the 9 steps eggs take farm to consumer?
- production
- collection
- cleaning
- sorting and handling
- grading
- packaging
- processing
- storage (refrigeration)
- distribution and shipping