Lely Vector feed quality research

Cows are selective eaters and search for the best. Therefore we strive for high-quality feed. However, various factors have an influence on feed quality. In this research, performed by Lely Farm Management Support, we investigated, among other things, whether we could quantify the extent of feed losses in the feed kitchen.

Management, Cow health, Feeding


Input is output, therefore a good harvesting and ensiling process are the basics. Thereafter it is recommended to have a clean and tidy face of the pit at any times with an correct feeding speed. Good quality feed in the feed kitchen is very important for every single cow fed by a Lely Vector. The definition of good-quality feed is as follows: for grass silage, a DM% of between 35 and 45; for maize silage, a DM% of between 32 and 35. The silage should be tasty and smell pleasant and the temperature of the feed should be <59°F higher than the ambient temperature during ensiling. Earlier research has proven that the temperature in feed rises when standing in the feed kitchen for longer than five days, when heating was already present. These temperature increases can cause undesirable feed losses. To what extent feed losses occur due to temperature increases has not been proven. Therefore research has been carried out on seven dairy farms in The Netherlands. 


The purpose of this research was to quantify the extent of feed losses in the feed kitchen, how these losses affect the rations of the milking cows and how they can be prevented. On each farm the ensiling and unloading management was investigated. In addition, a single grass silage block and maize silage block were set apart in the feed kitchen for five days in a row. These blocks were measured for temperature and feed samples were taken for feed value research. 


The results have shown that heating in silage can be seen as one of the greatest sources of feed losses. After five days, the silage blocks, where heating was present, had a significant (P=0.00) temperature increase at a depth of 20 inches of 33.8°F in the grass blocks and 36.86°F in the maize blocks (Figure 1). Due to heat, lower feed values for dry matter and energy and a higher NH3 fraction have been shown. As a result, a higher butyric extent is seen in the heated grass blocks and a lower starch content is seen in the heated maize blocks (Figure 2). The changes in the feed values have not been proven to be significant (P>0.05). However, heated silage causes lower energy and protein contents in the rations for cows. In the worst case, heating can lead to 188.50 lbs less FPCM per day for an average herd of sixty cows.

Figure 1 and 2

Prevent heating

The presence of heating is influenced by the ensiling and unloading management of each farm. Therefore a recommendation for farmers and Lely advisors is to pursue a good ensiling and unloading management. This means: harvesting at the correct DM%, using silage additives when needed, packing the silage with enough weight, covering the silage so that it is airtight and pursuing a high feed-out rate. In this way good-quality silage is formed and feed losses in the feed kitchen are reduced. 

Presence of heating

So, when is heating present? Heating is present in the silage pit when the difference between the silage temperature and the ambient temperature during ensiling is 59°F or more. Heating is present in the feed blocks when the difference between the temperature of the upper and the lower layers of the block is 50°F or more. This can be detected using a silage/hay thermometer that is 20 inches long, or a simple cooking thermometer that is at least 4 inches long.

How to deal with heated blocks

When heated feed blocks are present in the feed kitchen, it is important that these feed blocks are used up as quickly as possible. This can be achieved by setting up these blocks as preferred blocks. This is done via the hand-held device as shown in the picture below. 


Secondly, it is possible to fill the feed kitchen more times per week to prevent heated blocks from standing too long in the feed kitchen. 

In addition, it is important to keep the feed kitchen clean and tidy. Feed residue needs to be cleaned up every day and when the feed kitchen is filled up with new feed. In the worst-case scenario, with a lot of heating, the feed kitchen needs to be cleaned up every day.

At the end remember it is better to prevent than cure, good harvesting and ensiling management are key to good quality silage.

Lely Farm Management Support