Maximum gain with this diet
ADAS researcher Tim Harrington says a daily liveweight gain of 0.7kg for dairy heifers over 10 months can be achieved by offering ad-lib untreated barley straw. This should be offered alongside a supplement containing at least 16% protein, such as maize gluten.
At 9-10 months (230-240kg) this should be fed at 3.5-4kg a head a day (or at 3kg a head a day plus 0.5-1kg of soyabean meal to improve protein quality). At 13 months (300kg) the supplement fed should be stepped up to 4-4.5kg a head a day, through bulling up to 4.5kg a head a day, and up to 5kg a head a day post service until safely in-calf (to meet a growth rate six weeks before and after service of about 0.8kg a head).
From 4-10 months he says growth should be restricted to about 0.65kg a head a day by offering good quality ad-lib straw plus 3kg a head a day of concentrates.