Yeast culture in feed piles on calf liveweight
FEEDING a yeast culture to early weaned calves can increase liveweight gain and boost returns by up to £8 a calf, according to one researcher.
Harper Adams University College researcher Simon Marsh told delegates at the BSAS conference, York, that milk was one of the main calf rearing expenses. "This is why much emphasis is placed on weaning calves at 5-7 weeks and encouraging concentrate intake. But the concern on antibiotics in feed has led to a focus on whether yeast cultures can be used instead to enhance calf performance," said Mr Marsh.
When tested in a college trial, feeding 10g a calf of Diamond V yeast boosted daily weight gains of Limousin x Holstein calves fed modest amounts of milk. "Only four litres of whole milk a day was fed and calves had free access to an 18% protein concentrate."
The reason for the extra gain was that feeding yeast tended to stimulate feed intakes. Bulls gained an extra 12kg and heifers 15kg more by 12 weeks, compared with animals fed no yeast.
Responses were achieved at a cost of £1 a calf for additional concentrate, which equates to an extra return of £8 a calf, assuming a value of 85p/kg liveweight, he said.
"But similar studies at other research centres have not shown this benefit of feeding yeast to calves." Mr Marsh believed one reason could be the low milk intake, as control calves in the study failed to achieve their target weight within 12 weeks.
He believed yeast could be easily included by mixing in concentrate. "We also added it to milk, but it is not soluble." *