Maize silage analysis key to balancing varied starch levels

Early maize silage analysis results are indicating varied quality, particularly when it comes to starch levels. Producers are therefore being urged to test forage stocks and adequately balance rations to maximise cow health and productivity.

Rob Fowkes, nutritional advisor at Quality Liquid Feeds, explains that he is witnessing two main scenarios across the farms he supports, which are maize silages with either low or high starch levels.

“There are health and productivity implications associated with both of these scenarios, be that ruminal acidosis from feeding too much starch, or reduced productivity due to poor rumen function from reduced levels,” he warns.

“For this reason, it’s critical that farmers get their maize silage tested to help them understand exactly what they’re working with. Rations can then be accurately balanced to drive cow health and productivity, while maximising the value of home-grown forages.”

For those with lower levels of starch, Rob recommends considering adding extra cereals to the ration.

“Imported whole maize is a very good option at the moment as it’s very competitively priced because of the high UK wheat price,” he explains.

“Another way to balance out low starch levels is to include sugar in the diet. For example, adding a molasses-based product, such as Dairy SugR, provides an economical source of carbohydrate, in the form of six carbon sugars.

“By including these six carbon sugars at 5-7% of the ration, overall efficiency, rumen function, and productivity will increase, which ultimately drive the bottom line.”

Liz Newman, northern nutritional advisor at Quality Liquid Feeds, explains there is huge milk from forage potential for those producers who have access to high starch maize. However, it must be balanced correctly.

“Higher starch levels in maize forage means higher propionic fermentation in the rumen which equals higher milk yields and milk protein. However, getting the fermentable metabolizable energy (FME) to effective rumen degradable protein (ERDP) ratio correct is essential to achieve this and minimise the risk of ruminal acidosis,” she says.

“For this reason, high starch maize silages need balancing with a higher degradable protein. One of the options is to include a ‘timed-release- protein’.

“Timed-release’ protein sources are unique, because the protein source is urea phosphate, which degrades at a similar rate to soya and rape within the rumen. This helps to increase rumen efficiency by supplying rumen micro-organisms with a constant supply of energy and non-protein nitrogen,” she adds.

“The key message here is to establish what you’re working with, and once you understand your starch levels, make changes to balance out the ration and ensure cow health and productivity is maximised.”

Increased ash readings

Stunted growth of maize plants meant that crops were chopped lower to the ground at harvest which has increased ash readings in forages.

“Ash carries unwanted microbes and bacteria which can cause heating of the TMR in the trough, reducing FME and rumen productivity,” explains Rob.

“Including a mould inhibitor, such as MycoCurb, within your molasses-based liquid feed can help reduce heating, keeping your ration cool and minimising the risk of producing mycotoxins,” he adds.