Forced molting

Forced molting, sometimes known as induced molting, is the practice by some poultry industries of artificially provoking a flock to molt simultaneously, typically by withdrawing food for 7–14 days and sometimes also withdrawing water for an extended period. Forced molting is usually implemented when egg-production is naturally decreasing toward the end of the first egg-laying phase. During the forced molt, the birds cease producing eggs for at least two weeks, which allows the bird's reproductive tracts to regress and rejuvenate. After the molt, the hen's egg production rate usually peaks slightly lower than the previous peak, but egg quality is improved. The purpose of forced molting is therefore to increase egg production, egg quality, and profitability of flocks in their second or subsequent laying phases, by not allowing the hen's body the necessary time to rejuvenate during the natural cycle of feather replenishment. The practice is controversial. While it is widespread in the US, it is prohibited in the EU. Commercial hens usually begin laying eggs at 16–20 weeks of age, although production gradually declines soon after from approximately 25 weeks of age. This means that in many countries, by approximately 72 weeks of age, flocks are considered economically unviable and are slaughtered after approximately 12 months of egg production, although chickens will naturally live for 6 or more years. However, in some countries, rather than being slaughtered, the hens are force molted to re-invigorate egg-laying for a second, and sometimes subsequent, laying phase. Forced molting simulates the natural process where chickens grow a new set of feathers in the Autumn, a process generally accompanied by a sharp reduction or cessation of egg production. Natural molting is stimulated by shortening day lengths combined with stress (of any kind). Before confinement housing with artificial lights was the norm, the Autumn molt caused a seasonal scarcity of eggs and high market prices.