1. Milk preparationMost calve rearers use milk powders to rear calves as opposed to whole milk. To reduce labour, it is essential that the milk preparation area be well set out and suitable for use. Milk replacer needs to be fed to calves at 38-42°C, so most calf rearers have put water heaters into their milk preparation areas. There is a wide range of water heating products, including electric, gas-powered and solar-powered heaters.