Start next year’s silage budget now
April is upon us and silage season is just around the corner. Have you calculated your requirements? Firstly, you should calculate your feed stock being carried over from last year. As a rough guide, length X width X height in feet, divided by 50, will give you total tonnes in the pit. This is a rough guide; it is the dry matter of the silage that will determine volumes.
Why should you try to calculate accurate silage requirements? As I advised here a few weeks ago, grass silage production is getting more and more expensive every year. Unfortunately, its quality can be variable, depending on weather, cutting date and grassland management/reseeding policy. Too much poor or average silage in the pit may in fact increase overall beef production costs.
First cut grass silage typically costs a farmer about €25 per tonne, or €250 per acre, when you include reseeding, liming, fertiliser, weed control and contractor charges.
By all means make sure that you produce more silage than your requirements, but try not to go overboard. Build in a 15% to 20% safety valve to provide for a longer winter due to poor weather, poor growth etc.
Remember that 300 tonnes of silage sitting in your pit will cost you in the region of €7,500 to produce, or 400 tonnes costs €10,000.
So how much silage do you require? Firstly, you should construct a table like the example below. Fill in the relevant details, and do a simple calculation of your requirements.
How much will each type of animal eat? The following guidelines are based on a silage of 20% dry matter.
Dry suckler cows will typically consume 45-50kg of silage per day. The amount will depend on whether you are feeding straw or not.
Sucklers with calves will consume 50-55kg of silage per day, along with some concentrates to provide sufficient milk production.
Weanlings will eat about 2% of their own body weight in dry matter, of which silage will usually make up 80%. For example, a 300kg weanling will eat 6kg of dry matter, and 75% of this equates to 22kg of fresh silage per day.
Stores will typically consume mostly silage during winter feeding, perhaps 80%-85% of their total feed intake. For example, a 500kg store will eat 35-40kg of silage daily. Finishers may not be so dependent on grass silage for winter feeding, because they may have access to alternative forages such as beet or maize. On a finishing diet, depending on breed and sex, an animal will consume 2% to 2.5% of their body weight in dry matter. During this period, total intake may be split 50/50 forage and concentrate. For example, a 600kg bullock will eat 12-15kg of dry matter, which equates to approx 25-35kg of fresh silage daily.
* Independent dairy and beef nutrition consultant Brian Reidy, Premier Farm Nutrition, can be contacted at brian@pfn.ie. (Last week’s article by Brian carried an incorrect author’s name).
