To formulate a ration, one must first determine the nutritional needs of the animal. This will be influenced by the age, sex and type of animal as well as the production system to which they are destined.

Ration composition

Once the nutritional specifications are decided upon, it is the task of the nutritionist to determine the mixture of feeds that will be used to achieve the required spec. There are many factors which can influence the combinations of ingredients that the nutritionist will use. The main one, however, is cost. The general objective is to create a ration that meets the nutritional requirements of the animal at the lowest cost.

You get what you pay for and what may appear to be a good value ration may not actually give your animals what they require. When buying ration, it is important to get quoted the overall nutrient content of the feed. This should inform you of the energy (UFL), protein PDI, crude protein (CP), crude fibre (CF), vitamins and minerals in your meal.

Ingredients

If you know the ingredients in your ration, then you can calculate its nutritional value using our What's in your Ration? tool, from the Irish Farmers Journal'sToolBox.

This handy tool gives information on a range of feeds including barley, wheat, maize grain, soya bean meal, citrus pulp, beet pulp, soya hulls, rapeseed meal, maize gluten, maize distillers, sunflower meal, palm kernel and wheat feed.

The tool provides information on each feed type, giving a brief description of the feed, the DM%, UFL/kg DM, PDIE/kg DM, CP% and CF%.

Nutritional terms

  • Dry matter
  • Dry matter (DM) is expressed as a percentage of the total weight of the feedstuff. The DM% accounts for all material remaining in the feed with the water moisture removed. All of the nutrients that the animal requires are in the DM portion of the feed, so we must take this into account when calculating feed values. Most feed values are expressed in relation to DM.

  • Energy
  • The common way to measure net energy is in units of feed for lactation (UFL). UFL is measured on a per kilo dry matter basis, and so is expressed as UFL/kgDM. A high-energy ration should be 0.94UFL/kg

  • Protein
  • Protein can be measured in a number of ways. Traditionally, crude protein (CP%) values were used, but it is now known that this measurement does not give a accurate indication of the amount of protein available to the animal. CP is calculated from the total level of nitrogen in the feed, which does not reflect what is absorbed by the animal.

    The most accurate way to determine the protein value is by using PDI values, which are expressed as PDI/kgDM.

  • Fibre
  • Crude fibre (CF) is the total amount of fibre in a feedstuff and is expressed as a percentage of the total weight. The digestibility of fibre varies from feed to feed, so some fibre sources provide more energy than others.

    Find out What's in your ration here