Water for calves

Water accounts for 70–75% of a calf’s body weight and is an essential nutrient. Calves perform best when fresh drinking water is available from birth.

Back to: Feeding dairy calves

Water is fundamentally important to rumen development and the optimal growth of young calves.

  • It is needed to support the rumen microbial population and promote good rumen development and function
  • All calves must be provided with fresh, clean water from birth
  • Fresh water should be provided in addition to milk or milk replacer
  • Providing water as well as milk replacer can increase growth rates by 38% and starter intake by 31%
  • Calves drink 1 litre/day of water during their first week of life, increasing to nearly 3 litres/day by 3–4 weeks of age
  • Providing warm water (16–18˚C) during cold weather may stimulate starter intake

In hot weather

Particularly in temperatures above 25°C, the calf drinks more water to maintain hydration and normal body function.

Quality and cleanliness

Site the water supply to avoid contamination from muck and to prevent spillage that would wet the bedding. Remove any feed or bedding from water sources daily and keep water buckets outside pens to reduce water spillage onto bedding, as shown in the picture below.


During periods of scours, dehydration results in reduced feed intake, feed conversion and growth. Scouring calves drink more water, so must be provided with continual access to water.

Useful links

Calf management guide

If you would like to order a hard copy of the Calf management guide, please contact publications@ahdb.org.uk or call 0247 799 0069.