Grass silage is not feeding out as well as expected on many dairy units to date this winter, with a number of producers not seeing the milk in the tank they would expect from their home produced feed.

That is the stark warning from Philip Ingram, ruminant technical manager at Cargill who said that although silage analyses look good on paper, with energy and protein above average, many producers have been disappointed at milk produced from such analyses.

“Milk yields don’t seem to be on target on many dairy units,” says Dr Ingram. “Intakes are reported to be good, but cows are not milking as well as we’d expect. Despite tweaking the ration, cows are still lacking that ‘spark’ to get the milk really flowing.”

He said that fibre – described by NDF, ADF and Lignin on forage analysis reports – is generally high this year. Fibre is the major component in forages and makes up a high proportion of the cow’s diet, but it is also the hardest nutrient to digest being much harder than protein, oil, starch or sugar.

“As well as being relatively difficult to digest, there is a big variation in the digestibility of fibre depending on factors like the time of harvesting, grass variety and weather condition. The digestibility of fibre from forages is the single biggest factor in determining whether or not the diet meets expectations.”

He also pointed out that while silages always and inevitably vary every year, the more digestible silages that can lead to acidosis, can be anticipated if silages have high digestibility figure. In this scenario, a buffer can be used and the situation rectified fairly easily.

However, Dr Ingram said the issues causing concern this year are not quite as easy to decipher in that the silage analyses (always a must on a regular basis) are not resulting in the feed value many would be expecting.

And although silage analysis is an essential first stage, the proof of the pudding is in the eating and – as is this year’s situation has shown – some fine tuning is needed.

"Always analyse – then moderate if required as the analysis isn’t foolproof," said Dr Ingram.

His conversations this season are around the lack of performance from what looks like, on analysis, decent quality silage, with the thinking being that the fibre isn’t releasing the energy it should be.

NDF includes all fibre – lignin that’s not digestible and cellulose and hemicellulose that is. Even two silages with the same lignin and NDF analyses may be different in digestibility as the tiny links that hold the plant together (structure) can vary in strength due to factors like variety, harvest, agronomic conditions. This seems to be the case this year in that they are not releasing the energy expected and therefore need a helping hand with an enhanced rumen buffer. As a result, Dr Ingram recommends improving fibre digestibility to release the feed value of the diet and promote milk yields.

“Products such as Equaliser Fibre+ can be very valuable in these situations,” he adds. “This product was developed specifically to create a better rumen environment for the fibre digesting microbes, and to boost their digestive capacity.

“It was a successful addition to rations in 2018 where forages lacked quality and were high in NDF. Although the 2019 forages have better protein content than the previous year, they may still need ‘help’ when it comes to releasing the energy from the NDF and ADF contents.”

Equaliser is a strong rumen buffer that has a buffering capacity 2.65 stronger than sodium bicarbonate and a proven track record of stabilising rumen pH. The addition of the fibre efficiency additive Amaferm – in the case of Equaliser Fibre+ helps to maximise fibre and energy utilisation in diets with high fibre forages.

“Including this product in diets has been shown to increase fibre digestion by around 30% and milk production by an average of 4.8%, giving a good return on investment,” adds Dr Ingram. “It helps to release the potential of home grow forages cost-effectively.”