The proportion of home-grown protein. In other words: the quantity of home-grown protein divided by the quantity of protein in the ration. Managing forage production effectively offers plenty of benefits to dairy farmers. “Poor management of the entire process, from producing the best first cut of silage grass to presenting the forage at the feed fence, can make a negative difference of around €7 euros per bale. Harvesting quickly and cleanly, then preservation in airtight conditions is vital,” says Sjon de Leeuw, management and strategy advisor at PPP Agro Advies.
A dairy farmer’s business model all depends on its farm management. De Leeuw: “Feed rations account for the biggest expense on a farm. Farmers feel the financial implications of buying minerals, concentrates and other ingredients. But one area they do have some control over is the production of protein.”
As much as possible from your own land
It is important to aim for the maximum protein yield from your own land, as this logically reduces the dependence on protein from external sources. Quantity and quality are both equally important here, as well as maintaining the right energy to protein balance in the ration. Too much protein can have a detrimental effect on the animals, so every farm aims for the optimum protein content in the bales or silage.
Influential factors on protein
“In practice, I regularly see wide variations in how much home-grown protein is produced on farms. In some cases, one farmer harvests less than 50 per cent protein from their own land while another farmer gets more than 65 per cent – even though the number of cows and hectares of grassland are the same. This suggests that farmers who produce more protein on their own land manage forage production and feeding far better,” says De Leeuw. According to the advisor, contributing factors include the harvesting method, the time of harvesting and the way of preserving. To ensure good preservation, the speed of harvesting and getting the grass wrapped airtight as quickly as possible are essential.
De Leeuw: “And bear in mind that the optimum dry matter content is around 40 per cent. You can work with percentages of 50 or higher, but that increases the risk of heating. But what makes this complicated is that the protein in drier grass is generally more rumen-resistant, i.e., of better quality. But the friction between drier grass increases the risk of heating.” One of the causes of heating is a higher dry matter content combined with inadequately sealed material. This effect can be amplified by a low face removal rate of the silage. The lower the removal rate, the longer the period that oxygen can enter the silage mass. And if oxygen is given free rein, heating will inevitably occur. Feeding bales uses up the forage faster, so the risk of heating in the bale is considerably lower than in silage.
Different bales for optimal rationing
The protein content of grass harvested in summer is often lower than in grass baled in autumn. The differences affect the ration and how the cow utilises that ration. De Leeuw: “To get an optimal percentage of protein from their own forage, it is important to mark the bales obtained from different harvests and have them analysed. This information means you know what you have and where it is stored. To keep the protein content at the same level, various bales can be mixed to create the ration. Autumn grass is best suited for dairy cattle. Provided it has been harvested properly, it is palatable and combined with a bale with an appropriately low protein content. A low-protein bale on its own is more versatile and can also be fed to pregnant or dry cows at any time.”