Small Organisms with a Great Effect—Live Yeasts in Cattle Feeding.

It is unquestioned that live yeasts have a positive influence on the rumen microbiota, but what should be considered when using them?

What are live yeasts and their benefits?

There is a wide range of yeast products on the market. In addition to live yeasts, there are various types of inactivated yeasts. In dairy cattle feeding, live yeasts in particular were found to have positive effects on rumen health and milk yield. Live yeasts are very small, single-cell microorganisms which, in the field of feed additives, are categorized as probiotics. In the EU, only live yeasts based on the strain Saccharomyces cerevisiae are used in ruminant nutrition. Field trials with live yeasts always show positive effects on the following parameters:

• Stabilization of the ruminal pH value and reduction of the risk of acidosis

• Increase of feed digestibility and feed intake

• Reduction of health risks such as mastitis or abomasal displacement

• Improvement of milk yield and milk components

How do live yeasts effect the rumen environment?

Through their metabolic activity, live yeasts can reabsorb oxygen from the rumen and thereby promote the growth of cellulolytic and lactate-consuming bacteria. This stabilizes the rumen pH and improves feed digestibility, ultimately leading to an increased feed efficiency. In addition, live yeasts produce micronutrients which support the animal’s metabolic processes.

What characteristics should live yeasts have?

Some criteria can be used to differentiate between the live yeasts that are available on the market. These should be considered for an effective use. One of the most important criteria is a sufficient dosage of CFU (colony forming units) /animal/day. CFU is a unit of measurement and describes the number of active, living yeast cells. A high dosage allows a rapid and reliable effect on the rumen microbiota. Studies show that increasing dosage levels linearly improve rumen and performance parameters. The daily CFU intake in dairy cows should not be lower than a value of 4x10¹⁰ CFU/animal. Besides a high dosage, storage and feed stability as well as a fast activity of the live yeasts play an important role.

Which live yeast combines all these criteria?

The live yeast product Biosprint^® (MUCL 39885) particularly stands out for its effective mode of action, which is especially due to a high dosage level. In dairy cows, Biosprint^® is recommended at 2x10⁹ CFU/kg dry matter. With an average dry matter intake of 20 kg per day, at least 4x10¹⁰ CFU are therefore available to the animal. This makes Biosprint^® one of the highest-dosed products in the dairy sector. Numerous activity and stability tests confirm the high quality of Biosprint^® and prove its usability in mineral feed as well as its stability in the TMR.

With the right dosage, success is only a matter of time!

In a field trial, Biosprint^® was compared with a competitor product and a preceding control group with no added yeast. Biosprint^® and the competitor product were dosed according to the manufacturer's recommendation. The trial showed that better effects on feed efficiency can be achieved with the higher CFU dosage of Biosprint^®. In this case, this means that the animals supplemented with Biosprint^® required less feed to produce the same amount of milk. The increased feed efficiency was confirmed by a fecal wash using a ‘Nasco Digestion Analyzer’. In this test, overall, less fecal residues with also a smaller particle size distribution were detected in the Biosprint^® supplemented group. This indicates an increased fiber digestibility.

Figure 1: Feed efficiency of a group supplemented with Biosprint^® [4.5x10¹⁰ CFU/h/d] compared to a competitor product [1.0x10¹⁰ CFU/h/d] and a preceding control group (without yeast supplementation).

Always keep an eye on the proper dosage!

The question of what CFU content your own mineral feed contains can be clarified quite simply by looking at the bag tag. All of the ingredients are always indicated there. If a mineral feed contains live yeasts, information on the strain used as well as on the dosage amount can be found in the section ‘zootechnical additives’.

One kilogram of mineral feed contains 400x10⁹ CFU. With a dosage recommendation of the mineral feed of 100g/h/d, the animals daily receive 40x10⁹ CFU. This corresponds to the necessary minimum dosage of live yeast of 4x10¹⁰ CFU per animal and day.

Don’t leave your success to chance: take a look at the composition of your mineral feed and talk to your feed consultant! For more information, please feel free to contact us.