Grass silage

Properly assess the protein quality

To ensure stable milk production and animal health, farmers should be able to correctly assess their silages. Special silage mediums during the silage preparation have become indispensable for highly productive animals and a well-functioning operation.

Protein degradation with various degrees of severity takes place during silaging. This has consequences for the nutritional value. The amount of bypass protein (UDP) and usable protein (nXP) declines while the amount of NPN compounds rises. There are also conversion and degradation processes within fraction A, the NPN compounds. If the fraction still consists mostly of free amino acids, there may be a more or less severe breakdown into ammonia and biogenic amines, depending on the process.

Please note our documents on the protein requirements of cows, which are available for download:

Unfavourable protein value
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Protein degradation is always negative, especially the increase of harmful ammonia in the silages. If the ammonia content is too high, this has a negative effect on the palatability of the silage. Too much ammonia can also mean that there can be no complete build-up of bacterial protein and that the transport to the liver through the blood won’t function optimally. This problem can increase particularly if the energy supply is too low. Ammonia is converted into urea in the liver and discharged through the kidney. When the content of soluble N increases in the blood, the liver and kidneys have to detox more. This may lead to problems with the animal’s health. It is also possible that the urea contents in the milk will increase. The ammonia can also rise in the rumen and cause sensitive damage.

Proteins and energy
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The protein utilisation and energy supply are closely related. Both have to be synchronised with each other in the composition of rations. If the energy supply is appropriate, the ammonia in the rumen – which is released from the NPN and the protein that is degradable in the rumen – is developed into microbial protein. If there is an imbalance, however, for example because the energy intake is inappropriate or the proportions of NPN and quickly degradable protein (fraction A and B1) are high, less microbial protein is built up. The result: the ammonia content in the rumen increases, is passed into the intestine or travels through the rumen wall into the blood circulation. It is then converted into urea in the liver. Since this process takes a lot of energy, there is the risk of an increase of both substances in the system.

This leads to metabolic disorders and the resulting diseases (e.g. laminitis, hypomagnesemia, ketosis). Additionally, the animals’ excretion thins out and may turn into diarrhoea, which in turn causes problems in hygiene. The reduced nutrient intake due to inflammatory processes in the intestines also has a negative impact on animal health.

The quality of the silage along with the energy and nutrient values thus have a direct effect on the health of the animals. The scope of the nutrient degradation and losses influences the efficiency of the microbial protein synthesis in the rumen. To utilise the reserves in this area, the right evaluation of the silage is an important place to start. The quality of the silage continues to be assessed on the basis of raw nutrients, but this is not enough. Grass silages should also be tested in respect to their fermentation quality and protein values, which is the only way to properly evaluate the quality and energy density. If these analyses are skipped, there is a risk of overestimating the generated grass silage in terms of its suitability as feed. And this can negatively affect the health and performance of the animals.

Siloferm and protein quality
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Organic silage mediums control the fermentation process and reduce losses. The use of Siloferm during fermentation, for example, specifically prevents the unwanted degradation of the nutrients. The density and composition of the nutrients mostly stay intact, which means that more energy is consumed with the staple feed.

Additionally, the unwanted enzymatic degradation processes towards NPN are reduced to a minimum. Grass silages treated with Siloferm thus have a pure protein content that is nearly comparable with the original material. They are also consumed more easily because of their improved palatability. The cows give more milk and it becomes much more easy to balance out the ration.

The same applies to BioCool. The nutrient quality, energy density and palatability are retained during the output, which also affects the efficiency of the microbial protein synthesis in the rumen. If the silage doesn’t have sufficient aerobic stability, however, the nutrient quality and energy density decline and the feed intake is reduced. The yeasts responsible for the reheating also disturb the digestive process in the rumen. Using BioCool actively prevents these processes: The treated silages have a significantly lower amount of yeasts. The animals’ energy supply is ensured, which promotes the microbial protein synthesis in the rumen and provides more nXP.