EGG QUALITY · How to identify eggshell quality defects and the causes. · How to identify internal quality defects and the causes.
EGGSHELL QUALITY Problem
Causes
Cracked/broken eggs: large cracks and holes % in production: increases with the age of the hen. 1–5 % of total production
Old birds (> 50–60 weeks) Mineral deficiencies or imbalance Saline water Diseases with ovary tropism High temperatures Mechanical damage during collection
Hairline cracks: very fine cracks that require efficient candling % in production: varies with the age and the % of cracked of broken eggs
Old birds (> 50–60 weeks) Mineral deficiencies or imbalance Saline water Diseases with ovary tropism High temperatures Mechanical damage during collection Infrequent egg collection
Star cracks: fine cracks radiating outwards from a central point of impact % in production: varies with the age, 1–2 % of the total production
Old birds (> 50–60 weeks) Mineral deficiencies or imbalance Saline water Diseases with ovary tropism High temperatures Mechanical damage during collection Infrequent egg collection
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
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
Sandpaper or rough shell: eggs with rough texture areas unevenly distributed over the shell % in production: the incidence should be < 1 %
Diseases with ovary tropism and avian encephalomyelitis Disrupted egg oviposition or egg retention Sudden increase of light during lay Water shortage
Misshapen eggs: shell marred by flat 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
Immature shell gland Diseases with ovary tropism Stress caused by frights and disruption Crowding
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