The importance of weighing calves to monitor performance and the value of Estimated Breeding Values (EBVs) are two of the key subjects being considered on the Orkney monitor farm.
During a visit to Millburn Farm, run by Steven Sandison, Quality Meat Scotland (QMS) chairman Jim McLaren was updated on the key messages emerging from the business’ monitor farm experience.
Millburn in the parish of Harray, on Orkney’s mainland, extends to 230acres while a further 100 acres is taken on a seasonal let basis. The farm is mostly down to permanent and temporary grass with about 20 acres of rough razing and 30 acres of barley, some of which is kept for feeding cows, but the majority is sold. Stocking consists of 100 Simmental cross and Saler cross cows with Saler, Simmental and Charolais bulls all being used.
The performance of the 2013 calf crop has been under careful scrutiny, said facilitator Graham Scott.
“Since the last meeting two new bulls have arrived on the farm – a Salers and a Charolais. The fact there is still a Charolais bull on the holding, rather than another Simmental, was very much influenced by the community group’s recommendations at the previous meeting during which resounding support for the performance of Charolais bulls was expressed,” said Mr Scott.
All of the weaned calves not earmarked for replacements have been sold and only
replacement heifers have been retained, with several replacement Salers purchased to add to the herd. Scanning has revealed that of 110 cows, only six were found to be empty.
The weaning weights of the 2013 born calves were on average 18.2kg heavier than in 2012. In terms of gross output, these 93 calves weighed only one tonne less than the 102 animals in 2012. At Millburn’s 2013 average sale price of £2.59/kg, this 18.2kg equates to a £47.14 per head increase.
“Although we will have to wait until November 2014 to compare the 2013 figures with QMS data for similar farms, it would be expected that Millburn would at least be above average as was the case in 2012,” added Mr Scott.
Given that the 93 calves in 2012 were produced from considerably fewer cows than the 102 in 2013, the decision to run fewer cows with the bull in 2012 may prove astute.
On comparing the data from the two years in terms of breeds, it was found that the increased weaning weights were primarily down to the Charolais steers and heifers, the average weaning weights of which increased by 24kg and 31kg per head respectively.
“Identifying why the overall weaning weights had increased from the previous year, it was generally accepted by all that it was due to the better growing season. Allied to the perceived increase in quality and quantity of grass was the fact that the farm was running at a lower stocking density,” observed Mr Scott.
The birth weights of the spring 2013 born calves were all recorded at calving using a hoof measuring tape. This made it possible to calculate with some confidence the daily liveweight gain of the calves after they were weighed at weaning. In all cases the Charolais outperformed all other breeds, underpinning the community group’s support for the breed.
The monitor farm community group has also been looking at whether the calves perform in line with the EBV figures of their sires and the performance of the offspring of three Charolais bulls was scrutinised.
Detailed records were taken of which calves needed assistance at calving in terms the use of ropes, calving jack or the need for a caesarean. What was found was that for calving ease, the EBVs of the bulls did mirror the actual level of intervention required.
A similar result was found for birthweight. The bull with the EBV for the lightest calves did produce the lightest calves and the heaviest calves were from the bull with the EBV for the heaviest calves.
However, the results looking at bull’s EBV figures for 200 day weight were less convincing. A number of possible factors for this were considered, including the fact that daily liveweight gain of the cattle was used as the benchmark, rather than 200 day weight which is strongly influenced by the milking ability of the mother.
In general, it was agreed by the community group that the exercise had shown EBVs to be of value and proved successful, even with a small sample size of calves. Furthermore, the EBVs had proven to be correct for what were viewed to be the two most important criteria for Millburn.
The community group believes there is further potential for Millburn to improve on the weaning weights and daily liveweight gains. This could be achieved by: selecting replacement heifers from proven cows (cows that have had at least three calves); selecting bulls with better EBVs for 200 day weight and further tightening the calving period (though this could be difficult as the bulls are currently only in for nine weeks).
The Orkney monitor farm is funded by Skills Development Scotland, run by NFU Scotland and supported by Quality Meat Scotland. The next meeting will be held in late January. Further information is available from the monitor farm facilitators George Baikie and Graham Scott of SAC Consulting, a division of Scotland’s Rural College (SRUC). They can be contacted on 01856 872698
Caption (L-R): QMS Chairman Jim McLaren joins monitor farmer Steven Sandison on his Orkney farm.