Having a shed full of hay at the end of the season may make you feel good, but will the quality of the hay actually meet the needs of the class of livestock you are aiming to feed? Hay which has been cut too late in the season has excess levels of NDF (Neutral Detergent Fibre) and low levels of protein and energy. This renders the hay or silage as low quality and is only suitable for maintenance of adult stock.
Silage is an excellent way of conserving fodder early in the season and minimising potential losses when trying to conserve feed when the possibility of weather damage is high. Always cut early for quality, before the plants mature as silage is expensive to make and should be targeted and utilised as a high performance fodder.
The quality of hay or silage is determined by three main parameters. These are: Neutral Detergent Fibre (NDF), Megajoules of Metabolisable Energy (MJ ME) and Crude Protein (CP). A feed analysis is needed to determine these factors. A feed test is an important management tool for any producer wether you are selling the hay or utilising it for your own livestock.
Many would be familiar with the terms MJ ME and CP but some may not understand NDF. NDF is a measurement of the fibrous bulk of a feed and determines the animal’s intake of dry matter. High NDF feeds have low forage intakes and Low NDF feeds have high forage intakes. Sheep and cattle require a certain level of fibre to keep the rumen functioning. NDF values below 30% can result in possible rumen health issues such as acidosis. NDF values above 50% will decrease forage intake.
When comparing feeds you not only need to know the quality but also the nutritional requirements of the animal and the aim for feeding i.e maintenance or weight gain.
If you had good quality hay or silage testing at 10.5 MJ ME, 12% CP and 50% NDF and poor quality hay or silage testing at 8.5 MJ ME, 7% CP and 65% NDF and we were feeding 20 kg lambs, their intakes on the two types of feed determined by the NDF value is 480gms and 360gms respectively.
This means that lambs on the good quality feed would be consuming 5.3 MJ ME and lambs on the poor quality feed would be consuming 3 MJ ME. A 20 kg lamb requires a minimum of 5 MJ ME per day and a minimum of 14% CP. This means without additional supplementation or access to good quality feed the lambs on the poor quality hay or silage will not be able to reach growth targets.
Quality hay and silage drives production. If you need poor quality fodder for stock maintenance or for a fibre source, there is always plenty of straw around or someone else who will be trying to sell off their poor quality hay. If you are cutting your own hay and silage, cut early for quality, as quality is often hard to buy.
Written by Tiffany Bennett, Livestock Consultant, Rural Solutions SA.
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