Offering calves chopped straw alongside starter pellets and avoiding feeding long straw in racks pre-weaning is the best way to maximise concentrate intakes and growth.
That’s according to Alex Bach from the Department of Ruminant Production of IRTA in Spain, who was speaking at the Mole Valley Farmers Calf Conference in Exeter on 12 June.
Dr Bach highlighted a trial that provided calves with 80-100g of straw chopped to 2.5cm, along with pellets. This increased starter pellet intakes by 30%, from 860g to 1,140g a head, compared with offering pellets alone. As a result, the calves grew better.
“That’s a very nice, very cheap and very effective thing to do. You feed pellets to calves and in a separate bucket you feed straw or poor-quality hay chopped to 2.5cm. They will not eat a lot of it, but your concentrate intakes will increase greatly and your gain will increase dramatically,” Dr Bach explained.
Any chopped grass forage of more than 65% neutral detergent fibre that is not a legume can have the same effect. This can include barley straw, oat straw or poor-quality ryegrass hay.
Dr Bach said the improved performance seen in the trial was partly because of the increase in rumen pH. This is due to the removal of acid from the rumen, which allows the animal to grow more.
The “toothpick effect” of the chopped straw also cleans the rumen papillae, which thins the keratin layer and increases the ability of rumen papillae to absorb nutrients, he said.
He stressed that providing long straw was a “disaster”, as the rumen of the young calf was not able to digest this type of forage and it did not provide the toothpick effect. Consequently, he strongly advised against providing racks of straw or any other forage to calves.