Hatchery Management Guide

Chick Pull and Processing

Chicks are ready to be taken off when most of them are dry and fluffed up, with a few (about 5%) still having some moisture on the backs of their necks. A common mistake is to allow chicks to spend too long in the hatchers so they dehydrate excessively. Dehydration of chicks may result from incorrect adjustment of setting time for egg age or excessive weight loss during incubation. Similarly, if they are “green”, e.g., not yet ready, check setting times and also check for opportunities for the eggs to have become cooled down in incubation, Reducing the rate of development.

Upon pulling chicks, they have to be separated from their debris, graded into first quality and culls, and counted into boxes. Some hatcheries carry out additional operations such as:

    • Sexing, primarily using feather-sexing with broilers but also Vent sexing with breeding stock
    • Vaccination, sprayed or injected, using hand or automatic vaccinators
    • Beak conditioning
  1. During processing, chicks must be held in a controlled environment that prevents overheating or overcooling. They must not be overcrowded in the boxes or while on conveyers. To reduce weight loss from the chicks, maintain the correct humidity in the chick holding areas. Aim for 23 °C (73 °F) with a relative humidity of 65 - 70%.
  2. Automated equipment has been developed to improve chick handling while reducing the number of staff involved.
  3. Avoid rough handling of chicks in manual operations and when equipment is used. Equipment must be correctly and regularly maintained.
  4. Clean all equipment thoroughly after each hatch. All chick contact areas such as conveyers and carousel must be easily accessible for cleaning.
8.1 Feather Sexing Broiler Chicks

Broiler chicks in the feather sexable - slow feather format, can be feather sexed at day old as illustrated below.

In the non-feather sexable - fast feather format, both males and females will show the same pattern of feather development illustrated by the diagram below relating to females.

8.2 The Hatch Window

The hatch window indicates the number chicks hatched after the eggs have been transferred from the setter to the hatcher.

If the eggs are hatching too early, the chicks become susceptible to problems such as dehydration. Dehydration of chicks this early could lead to increased 7 and 14 day mortality and poor broiler performance. If the chicks are hatching too late the result could be poor hatchability, chick quality problems, increased pipped eggs and live embryo unhatched eggs.

Factors affecting early hatch include:

  • Extended pre-heating periods
  • Setting eggs too early. Too many hours of incubation
  • Incorrect setter/hatcher temperature and humidity
  • Hot spots inside the setter and hatcher
  • Incorrect ventilation
  • Seasonal temperature changes effecting the hatchery environment
  • Too many fertile eggs in the hatcher
  • Egg size

Factors affecting late or delayed hatching include:

  • Setting eggs too late
  • Incorrect setter/hatcher temperature and humidity
  • Incorrect ventilation
  • Seasonal temperature changes effecting the hatchery environment
  • Eggs which have been stored for long periods
  • Eggs which have stored at too low a temperature
  • Incorrect setting patterns in multi-stages machines
  • Disease and fertility problems

The bar graph above indicates eggs which were in the top, middle and bottom positions in the setter and then transferred to the hatcher.

Ideally, no more than 25% of the total hatch should be hatched 23 hours before pull and more than 75% of the total hatch should be hatched 13 hours before pull.

This bar graph indicates the correct number of chicks hatching spread over the 23 hours prior to pull. The number of chicks hatched in each hatcher basket / tray should be even throughout the hatcher.