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How to boost rumen function at grazing for more milk solids.

Whist the cows may be happy to be out, a change to lush, lower fibre grass is a challenge for the rumen. The resulting loose, liquid manure isn’t just a hazard for milkers, it is a sure sign of lost milk production and/or milk quality. Loose manure suggests poor rumen function, especially if gas bubbles and undigested fibre are seen. Over time, acidosis can also be a risk.

The change in diet from winter TMR to spring grass has a major impact on the rumen, the rumen microbiota and feed digestion. Trials have proven that improving fibre digestion and stabilising the rumen pH with the rumen specific live yeast Levucell SC can help, increasing milk yield and quality.

Live yeast trials at grazing

Studies have shown the benefits being achieved with Levucell SC at grass. An early study in Northern Ireland* showed a +2.3kg/cow/day improvement in cows fed the rumen-specific live yeast during the transition from winter diet to grazing. (*Donaldson et al, 2000)

Kevin Gleeson and Anne Sugrue in Co. Tipperary run 147 mainly spring calving Holstein cows between a Lely A4 Robot and a herringbone parlour. They took part in a trial over four months, from May to August 2019.

The trial involved 55 robot-milked cows, 27 of which received Levucell SC (1X1010 cfu/h/d) TITAN with their 5kgs of 14% cereal based dairy nut, while the remaining 28 received no additional supplementation.

Trial Results

The results impressed: cows supplemented with Levucell SC produced on average 0.5L more milk per day with significantly higher fats and proteins than non-supplemented cows. The table below shows the difference in milk yield and quality between the two groups

Milk performance at grass	Control	Levucell SC
Milk yield (kg/d)	28.70	29.22 (+0.52)
Milk protein (%)	3.39	3.43
Milk fat (%)	3.97	4.14

The additional milk solids versus the cost of the yeast gave a return on investment of 6:1"

Once we saw the difference we put our other herd onto Levucell SC. It didn’t take long for these cows to start presenting much cleaner.”

How Levucell SC can help

Levucell SC is a rumen-specific live yeast strain (Saccharomyces cerevisiae CNCM I-1077) selected by Lallemand and INRA in France for its ability to increase fibre digestion and stabilise rumen pH. This reduces the risk of SARA (Sub Acute Ruminal Acidosis) that can lead to reduced milk quality, lower milk solids, and poor cow health.

Levucell SC can be added to minerals, blends, compound feeds, or farm rations.

Pellet Stability

Like many other biological feed additives such as vitamins and enzymes, live yeast is sensitive to external stresses such as heat, moisture, pressure or contact with certain chemicals or trace elements.

One of the challenges of including a live yeast in supplementary feed for grazing is that the pelleting conditions (hjeat/moisture etc.) needed to make these higher fibre pellets can harm/kill live yeast. To avoid this, the yeast must be protected to ensure stability during pelletisation and also during storage.

Levucell SC TITAN is the only live yeast on the market to benefit from a patented method of micro-encapsulation called TITAN.

Pellet stability trials

Benchmarking studies performed by recognised, independent institutes have demonstrated the higher stability of TITAN versus other non-coated yeast sources (see figure 1).