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Egg quality

  • How to identify eggshell quality defects and the causes.
  • How to identify internal quality defects and the causes

Problems and Causes

Problem

Cracked/broken eggs:

  • Large cracks and holes
  • % in production: increases with the age of the
    hen.
  • 1–5 % of total production
Causes

Old birds (> 50–60 weeks)

Problem

Hairline cracks:
Very fine cracks that require efficient candling

  • % in production: varies with the age and the %
    of cracked of broken eggs
Causes
Problem

Star cracks:
Fine cracks radiating outwards from a central
point of impact

  • % in production: varies with the age,
    1–2 % of the total production
Causes
  • Old birds (> 50–60 weeks)
  • Mineral de#ciencies or imbalance
  • Saline water
  • Diseases with ovary tropism
  • High temperatures
  • Mechanical damage during collection
  • Infrequent egg collection
Problem

Shell-less eggs and thin shelled:
no shell or very thin shell, very easy to break

  • % in production: varies 0.5–6 %.
    High levels possible with pullets in early maturity
Causes
Problem

Sandpaper or rough shell:
eggs with rough texture areas unevenly
distributed over the shell

  • % in production: the incidence should be < 1 %
Causes
  • Diseases with ovary tropism and
    avian encephalomyelitis
  • Disrupted egg oviposition or egg retention
  • Sudden increase of light during lay
  • Water shortage
Problem

Misshapen eggs:
shell marred by $at sides or body checks (ribs or
grooves)

  • % in production: can rise to 2 % at start of lay
    and later almost disappear unless there is an
    issue
Causes
Problem

Flat sided eggs:
part of the shell is flattened

  • % in production: < 1 %
Causes
Problem

Pimples:
small lumps of calci#ed material on the eggshell

  • % in production: around 1 % is common
Causes
Problem

Pinholes:
small holes in the eggshell

  • % in production: < 0.5%
Causes
  • Old birds
  • Mineral deficiencies or imbalance
  • Damage caused by hen or sharp objects in
    cages or collection conveyor
Problem

Mottled or glassy shell:
appears mottled at candling

  • % in production: not usually undegraded unless
    the condition is obvious. Incidence varies
Causes
  • High humidity in the layer house
  • Mineral de#ciencies
  • Crowding
  • Diseases with ovary tropism and infection
    bursal disease in parent stocks

Albumen quality

Yolk quality

Problem

Blood spots:
blood spots on the surface of the yolk

  • % in production: incidence varies, 1–2 %
Causes
  • Deficiencies in vitamin A and K
  • Fungal toxins
  • Continuous light programs or intermittent
    light periods
  • Fright and disruption
  • Avian encephalomyelitis
Problem

Meat spots:
brown colored, pieces of tissue of the ovary or
partially broken-down blood spots

  • % in production: 1–3 %
Causes
  • deficiencies in vitamin A and K
  • Fungal toxins
  • Continuous light programs or intermittent
    light periods
  • Fright and disruption
  • Avian encephalomyelitis
Problem

Pale yolks:
the egg yolk doesn’t have the expected color

  • % in production: incidence varies based on the
    issue
Causes
  • Gut health issues
  • Mycotoxines
  • Liver damage
  • Oxidation of the added pigments
  • Wrong mixing of the pigments

Key Points

  • Internal and external egg quality is a powerful tool to address production issues.
  • A certain percentage of defects is considered normal.
  • Correct egg management is the best way to improve internal and external egg quality.

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