Organic beef herd shows promise in growth rate study
By Wendy Short North-east correspondent
ORGANICALLY-REARED calves from the beef suckler herd at the ADAS High Mow-thorpe research centre have put in a creditable performance compared with conventional animals.
During summer grazing last year, daily liveweight gain in the organic animals averaged 0.78kg, compared with a 0.97kg/day increase in the conventionally-reared animals. Both groups were born in spring 2001.
The difference in weight gain can be explained by the lack of flexibility of grazing on the organic grassland, which makes up just a small proportion of the farm, says ADAS head of farming Neil Pickard.
"I think it occurred because there were more options for grazing the conventional cows, so they produced a bit more milk. There were also stocking rate differences.
"But I am not worried about these slight discrepancies. They are on an 18 month-two year system, so there is no need to push for fast growth rates in the early stages. I am expecting them to catch up later."
The 25 organic Limousin cross cows and their Limousin-sired calves have remained healthy throughout the study, which is being carried out with support from Marks & Spencer.
No special vet attention has been needed and neither have any animals received large inputs of concentrates.
However, calves were given creep access to 2kg/head/day of rolled beans for 65 days during housing. They were also offered ad-lib silage.
Winter daily liveweight gains for organic cattle averaged 0.56kg, compared with 0.68kg among conventional calves. Organic calf bodyweights at turnout this summer were 264kg, with conventional calves weighing 313kg. *
Organic Limousin-sired calves weighed 264kg at turnout, compared with 314kg for conventionally reared animals, says Neil Pickard.
• Growth rates good.
• Little concentrate fed.
• Minerals essential.