Water is essential for birds. If water uptake is too limited, both digestion and metabolic functions are impaired. However, excessive water intake has a negative influence as well, especially on the litter quality.

As breeders in production but especially in rearing are restricted in feed intake, they will try to drink more then necessary for optimal functioning. As a result, the manure and litter will become wet, which has a negative influence on bird performance, leg and foot pad quality and climatic conditions in the house.

It is recommended to restrict water intake for the birds, both in rearing and in production. Water restriction should focus on limiting the water intake towards the optimal level for the birds to function. Although especially in hot climates water restriction is not applied commonly, water restriction is possible in all climates, although it should be used with care.
There are two possible ways to restrict water, either by allowing the birds to drink for a certain period of time, or to allow the birds to drink a certain quantity of water. In both cases, careful registration of the water intake must be applied.

- Give water at the same time as feed is given, as the birds need water to digest the feed.
- Make sure that per kg of feed at least 1.6 liter of water is used in rearing, and minimum 1.8 liter of water in production.
- The maximum amount of water under normal climate conditions should not exceed 2.0 liter of water per kg of feed in rearing, or 2.2 liter of water per kg of feed in production.
- If water is restricted by shutting of the system after a certain amount of time, normally water is given for approximately 4 hours (depending on the drinking system). If water restriction in time is applied, a control on the total amount of water used must be implemented.
- Bell drinkers allow birds to drink faster than cup drinkers do, and birds drink faster on cup drinkers than on nipple drinkers. As the amount of water that birds is important, drinking time has to be adjusted to the system used, to ensure that birds drink the quanity that they need.
- Some watering systems spill more water than others. When a system spills more water, the water to feed ratio has to be increased, as the birds need a minimum of water going through their intestines.
- If climatic conditions can not be controlled fully, give an additional amount of water at the end of the light period, for instance during 1 hour.