Weaning times vary from farm to farm, with the availability of shed space, waste milk and cash often dictating the age at weaning, according to Sue Bryan, head of technical at feed company NWF agriculture.
However, Ms Bryan said farmers should look for just one sign to prompt weaning– the sign the calf gives you.
“It tells you by the amount of concentrate it eats,” added Ms Bryan, who said the aim should be for calves to be eating 1.5kg of concentrate/day prior to weaning.
Speaking at UK Dairy Day this week (14 September), Ms Bryan said these first few weeks were a critical stage in the animal’s life, with rumen development ultimately driving milk production in the heifer’s first lactation.
She advised farmers to feed plenty of roughage alongside milk such as straw to promote rumen papilla.
Ms Bryan said recent research compiled by Trouw Nutrition showed an additional 1g weight gain at weaning equated to four extra litres of milk in the first lactation.
With this in mind, she said instead of looking to cut costs by weaning earlier, farmers should capitalise on the phenomenal feed conversion rates (FCRs) in young animals, with FCR from milk close to 1:1.
“A calf will grow at three times the weight of a bull. The feed conversion at that stage is phenomenal and we need to exploit it.”