Buying feed – need to know
Consider getting your feed tested and checking that it's safe for your livestock.
When sourcing feed supplies there are a couple of key issues worth considering before securing a seemingly cheaper feed: feed testing and commodity declarations, so you know exactly what you are getting. This will ensure that the feed value is high enough, and hence give you value for money and peace of mind that it is safe to feed.
1. Get the feed tested
Testing of feed sources for key nutrients is even more crucial when the costs are high and the source is new. For example, in 2006–07, when canola hay was last cut widely and fed to stock, FeedTest values ranged from 4.1 to 13.1 in energy value as MJ ME/kg DM (megajoules of metabolisable energy per kilogram of dry matter), and protein ranged from 4% to 27.2% crude protein.
This represents a fourfold range in energy value and an even wider range for protein content. The lowest values represent a low-grade feed that would be unable to sustain stock, and the high end represents high-quality feeds similar to good grain. Even small ranges in quality can mean large cost differences.
There are other nutritional considerations, such as fibre and intake potential. For example, some fodders that are high in fibre or water can limit intake and the ability of stock to eat as much as they need to. The main feed components that can be tested are energy, protein, fibre and dry matter.
Because energy is the main requirement of livestock, knowing the metabolisable energy (ME) values of different feeds is critical to working out how much you need to feed and the best value (as cost of energy) to buy. A feed analysis report will report on ME, expressed either as MJ ME/kgDM or as megajoules per kilogram of dry matter (MJ/kgDM). ME is the amount of energy in the feed that is available for sheep to use. It involves measurement of energy excreted in faeces and urine, and exhaled as methane.
Proteinis measured as the crude protein (CP), as a percentage of dry matter. Protein contains nitrogen, and this is used to estimate the protein content of feeds. A portion of the nitrogen in feed is nonprotein nitrogen (nitrates, ammonia and urea); crude protein is a measure of both this and the feed protein (amino acids). Crude protein values give a good indication of whether a particular feed will satisfy the protein needs of an animal.
Fibre is measured and reported as neutral detergent fibre (NDF) and acid detergent fibre (ADF) as a percentage of dry matter. NDF is a measure of all the fibre (the digestible and indigestible parts) and indicates how bulky the feed is. ADF is a measure of the proportion of feed that is indigestible to stock (mainly cellulose and lignin). Feeds with a high ADF are low in energy. If both NDF and ADF are reported and the ADF represents a high proportion of NDF, this means that most of the fibre content in the feed is indigestible to stock.
All measurements of energy and protein are made on a dry matter basis, so feeds of different moisture contents can be compared. Dry matter is the amount of feed left after all the water in the sample has been removed by oven drying. It is expressed as a percentage of the original sample. Knowing the dry matter percentage enables you to work out how much to feed to meet the energy requirements of the stock.
Other components of a feed analysis
Digestibility is provided on a feed analysis report as a percentage of dry matter — either DDM (digestible dry matter) or DMD (dry matter digestibility), depending on the company doing the analysis. It is the percentage of the dry matter actually digested by the animal. High-quality feeds will have a figure above 65%. Feeds below 55% are of poor quality — even if sheep are given free access, they will be unlikely to maintain their live weight if this feed is supplying all of the diet.
Digestibility of organic matter is expressed as a percentage of dry matter. It is a measure of the digestibility of the organic component of the feed. It takes into account the inorganic component (referred to as ash), such as sand, dirt and clay, that may be present in the sample.
Ash is reported as a percentage of dry matter. It is the inorganic material — sand, dirt and clay — present in the sample that is not used by the stock.
Fat is expressed as a percentage of dry matter and is a measure of the lipid content of the feed. If the diet of sheep is too high in fat (greater than 5%), intake will be reduced.
Water-soluble carbohydrate is reported as a percentage of dry matter. It is a measure of the total naturally occurring sugars in the feed. Sugars are a highly digestible source of energy for rumen bacteria and therefore sheep.
Note that not all companies test and report on the same components. Metabolisable energy, protein, NDF and dry matter are key components to have tested.
When sourcing feeds, ask for the feed analysis before you buy. If a test is not available, it may be possible to get a sample and send the test off yourself before deciding whether to buy. If you buy feed without a test, it is still worth taking a sample and getting a test done so that you can fine-tune your rations and assess whether all requirements are being met.
A number of companies (listed below) do feed tests and can provide follow-up advice if needed. Their websites will provide details about how to sample, costs involved, how to access sampling kits and payment methods:
- FEEDTEST®, Werribee
Phone: 1300 655 474
- Livestock Logic, Hamilton
Phone: 03 5572 1419
- Feed quality services, NSW DPI, Wagga Wagga
Phone: 1800 675 623
- Quality Testing; (hay), Wimmera Mallee
Phone: 0429 200 670
- Hunter Group, Shepparton
Phone: 03 5833 3999 (option 5)
- BR&C Agents, Barham
Phone: 03 5453 1296
2. Check that the feed is safe for livestock
When sourcing feeds, particularly new sources, or fodder from failed or harvested crops not originally intended for livestock, we recommend that you obtain a commodity vendor declaration form. This will provide some background about the feed source, including whether it has been sprayed or treated with a chemical that is still within a withholding period (WHP), export slaughter interval (ESI) or export animal feed interval (EAFI).
A commodity vendor declaration can be downloaded from the Meat & Livestock Australia website.
For feeding and managing sheep through droughts see:
- Drought feeding and management of sheep guide (PDF - 2.7 MB)
- Drought feeding and management of sheep guide (WORD - 307.3 KB)
This resource also includes information on stock containment and water supplies.