Egg quality

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)

  • Mineral deficiencies or imbalance
  • Saline water
  • Diseases with ovary tropism
  • High temperatures
  • Mechanical damage during collection
Problem

Hairline cracks:
Very fine cracks that require efficient candling

  • % in production: varies with the age and the % of cracked of broken eggs
Causes
  • Old birds (> 50–60 weeks)
  • Mineral deficiencies or imbalance
  • Saline water
  • Diseases with ovary tropism
  • High temperatures
  • Mechanical damage during collection
  • Infrequent egg collection
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 deficiencies 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
  • Immature shell gland
  • Disrupted deposition of calcium in shell
  • Mineral deficiencies or imbalance
  • Saline water
  • Diseases with ovary tropism
  • Mechanical damage during collection
  • Infrequent egg collection
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

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

  • % in production: can rise to 2 % at start of layand later almost disappear unless there is an issue
Causes
  • Immature shell gland
  • Diseases with ovary tropism
  • Stress caused by frights and disruption
  • Crowding
Problem

Flat sided eggs:
part of the shell is flattened

  • % in production: < 1 %
Causes
  • Diseases with ovary tropism and avian encephalomyelitis
  • Disrupted egg deposition
  • Sudden increase of light during lay
  • Crowding
Problem

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

  • % in production: around 1 % is common
Causes
  • Old birds
  • Excess of Ca
  • Sudden increase of light during lay
  • Crowding
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 at the farm
  • Mineral deficiencies
  • 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