Natural moulting in poultry
Before poultry obtain their adult plumage, they undergo a number of natural moults at several stages of their life. The first moult starts when the chick is about 6–8 days old, when the down is replaced with feathers. This moult will usually last until the bird is 4 weeks old.
Male birds moult before females. Feathers are first lost from the head and neck, then the breast, and finally the tail and wings. Moults can be partial (occurring on particular parts of the body) or complete.
The extent of moulting depends on the breed and individual bird. The length of the moult varies, occurring over a few weeks or a few months.
Moulting in pullets
Before pullet hens (young hens less than 1 year old) start to lay eggs, they will go through 1 complete moult as a chick and then 3 partial ones. These partial moults generally occur at 7–9 weeks, 12–16 weeks and 20–22 weeks. The stiff tail feathers grow during the final moult.
Moulting in adults
Adult birds will normally moult once a year. Some may moult twice in 1 year and in rare occasions, once in 2 years.
The first adult moult will usually occur at 16–17 months, depending on the time of year the hen started laying. During the moult, egg production ceases while the bird builds up its nutrient reserves. This is the most important moult for producers.
Moulting in cockerels
Cockerels (male chickens or roosters) also moult. While undergoing a moult they are nearly always infertile because they lose weight and their reproductive physiology is in a resting phase.
Take care to ensure cockerels do not lose more than 25% of their body weight while moulting as this can lead to sterility.