The past rain season came as a huge relief to all – nature and animals included. But although the veld is abundant it’s important to remember that its nutritional value decreases drastically in autumn when grass begins to produce seeds. This happens because the plant moves easy digestible carbohydrates to the roots and the stems and leaves are left with a high percentage of lower digestible roughage.
Roughage is generally measured as neutral detergent fiber (NDF). Apart from the fact that the NDF of natural grazing increases from about 55% to 75%, lignification also increases. Lignin is completely indigestible and also binds to NDF which also decreases the digestibility of NDF. Furthermore, NDF also lowers the intake of grazing, which results in a decrease of total energy – a double whammy!
Along with the increase in percentage of lower digestible carbohydrates, a decrease in the percentage of protein also takes place. Protein from grass is mainly broken down to ammonia in the rumen by microbes. Ammonia is necessary for the digestion of NDF and a shortage can lead to the demise of microbes, low NDF digestibility and lower energy provision for the animal.
The question is thus what to do with winter grazing. Firstly, it is important to maximise fiber digestion by supplying urea containing licks. Urea is completely broken down in the rumen to ammonia which is crucial for the growth and increase of fibre digesting bacteria.
Secondly, it is important to provide for the micro and macro mineral needs of the animal. These nutrients should be standard in all winter licks, especially sodium, chlorine, calcium and phosphorus.
Maintenance licks as supplement on good quality grazing should be sufficient for the needs of adult dry animals in winter.
The Winterlek 40 from Sernick Veevoere is an excellent lick for cattle on winter grazing and can be supplemented at 500 to 700 grams per day to medium size cows and 600 to 800 grams per day to larger frame cows.
For sheep, the Sernick Veevoere Wolskaaplek is a multipurpose lick for all sheep breeds and can be supplemented at 100 to 150 grams per day for dry ewes and wethers on winter grazing for their maintenance needs.
Thirdly, the physiological stage of the animal should be taken into account. Maintenance lick for young, growing animals as well as pregnant or lactating animals will not be sufficient in winter. These animals need additional energy and protein in the form of production lick. Sernick Veevoere has various production licks that are tailored to the needs of livestock farmers. For example, the Presisie Lakterende Ooilek is ideal for pregnant and lactating ewes and can be given at 200 to 500 grams per day per ewe in winter, depending on the condition of the veld as well as the animals.
It is important to note that excess urea is toxic to ruminants and that the prescription on the bag descriptor should be read carefully before feeding.
The choice of lick and the amount per animal per day is dependent on various factors of which the condition of the grazing and animal is the most important. Contact your local Sernick Veevoere technical advisor for specific recommendations.