First week mortality is an indicator of day old chick quality at the hatchery. Hatchery hygiene is one of the parameters to maximize chick quality (other than setting the eggs at the correct program in terms of temperature, humidity, ventilation and turning, which is more accurate with sealed single stage incubators than with multistage machines, that cannot be cleaned and disinfected every 18 days).
But chick quality equally refers to hatching egg management ( egg storage, egg hygiene (no dirty eggs in the setter) , avoiding hair line cracks during egg transport, etc).
You can get a good chick out of a good egg; you can never get a good chick out of a bad egg!
