Feed too much starch and cows can skate on the edge of sub acute rumen acidosis, but keep the ration too tame and milk output and cow fertility can suffer.
This is exactly the problem that dairy farmer, Neil Parkhouse, faced. Neil farms at Treveor, Gorran in Cornwall and his herd of 600 cows is milked three times a day. Cows are housed all year around and have averaged around 11,300 litres/cow/year, although yields have dropped back slightly as Neil has sought to maximise the returns from his milk contract.
“We supply milk to Dairy Crest at Davidstow and so we are paid on a compositional basis,” he explained. “As such it is in our interests to improve fat and protein levels, even if this means a slight reduction in yield.”
Whilst yields have dropped back slightly to 11,100 litres/cow/year, fat has increased from 3.55 per cent to 4.1 per cent, which has more than made up the difference financially.
Herd performance is excellent, with a calving index of 384 days and an average days in milk of around 150 excluding culls. Neil has a strict culling policy for fertility, with a ‘three serves and their out’ approach keeping calving patterns tight.
Cows are fed a mixed ration to provide M+34 litres and then topped up to yield throughout of parlour feeders, with the maximum supplementation of concentrate being capped at 9kg/cow/ day. Despite a single TMR ration, cows are managed in three groups – highs, lows and heifers – and cows are typically dried off giving around 28 litres/day.
“Cows are typically eating 19-20 kg/DM of mixed ration each day and we are really trying to push forage intake,” Neil said.
The ration comprises grass silage, maize silage, straw, soya, molasses, home grown barley and rape extract. Neil takes four cuts of grass silage each year and focuses on quality rather than quantity with each cut. Megalac is fed for energy and cows are on a mineral pack, which includes Actisaf® live yeast.
“We added Actisaf® on the advice of our Mole Valley Feed rep, Dave Higman, and Mole Valley’s senior nutritionist, Dr. Robin Hawkey, as we were seeing a few issues with sub acute rumen acidosis,” Neil explained.
“We work on a vet contract and have used eCow boluses to monitor rumen pH in the past, which showed some problems with rumen pH falling below 5.8 and spiking quite badly after feeding time. We tried adding a chemical buffer to see if that would help address the problem, but it didn’t really help so Dave suggested we tried feeding Actisaf® instead of the buffers. Actisaf® definitely worked – rumen pH settled down and both dung scores and cudding scores improved.”
As a result, Actisaf® is now a core component of Neil’s mineral pack and is there to stay. “Actisaf® definitely took the edge off the SARA issues that we were witnessing within 3 or 4 weeks of starting to feed it. What’s more, milk yields improved by around 1 litre/cow/ day as well,” Neil concluded. “We were impressed and it is now something that we always include in the ration.”