Budgeting fodder supplies this winter – Baled silage
By Don Morrow, Beef & Sheep Development Branch, CAFRE
Baled silage represents a significant proportion, and in some cases all, of silage stocks on many beef & sheep farms. The question often asked at his time of year is “How much feeding is there in a bale of silage?”
There are two aspects to this question – quantity and quality.
Quantity - There is a considerable variation in the weight of bales – a lot of this variation will be due to water content. Baled silage can vary from 18 percent dry matter (DM) to more than 40 percent. Assuming the same size and packed equally tightly (chopped bales will be more tightly packed), the data in Table 1 summarises possible weights and dry matter content of a range of bales.
Table 1. Effect of dry matter on weight and feeding days of baled silage
| Dry matter | Overall weight | Dry matter weight | Cow feeding days |
|---|---|---|---|
| 18% (wet) | 715kg | 129kg | 10 |
| 25% (average) | 600kg | 150kg | 12.5 |
| 40% (dry) | 400kg | 160kg | 15 |
In other words a heavy wet bale of silage may contain 20 percent less dry matter than a dry bale. Water has a very poor feed value! The feeding days calculation assumes that cows are fed to appetite and all the bales are properly preserved – mouldy bales will reduce feed intake and increase wastage.
Quality - As with clamp silage there can be a considerable variation in the feeding quality of baled silage. As the grass becomes more mature its feeding value is reduced. The data in Table 2 demonstrates the effects of cutting date on silage quality assuming that the silage is ensiled in good condition and well preserved.
Table 2. Effect of cutting date on silage quality
| Typical quality | ||
|---|---|---|
| Cutting date | Energy (MJ/kg DM) | Protein (% DM) |
| Early e.g 20 May | 11.5 | 16 |
| Mid e.g 10 June (average) | 10 | 14 |
| Late e.g 25 June | 9 | 9 |
This means that a 25 percent DM bale cut in late May will have 150MJ more energy that one cut in late June. This is equivalent to the energy contained in 35 kg of concentrate (currently worth about £5.50).
Contamination: Given the poor silage making conditions for late first and second cuts soil contamination is likely to be more common. Soil contamination increases waste and the likelihood of listeriosis especially in sheep.
When buying bales
Consider the quality and dry matter content of the silage. High dry matter, late cut bales will last longer when fed but have a lower feeding value in terms of weight gain and may suit feeding dry cows best.
Damaged bales will have more waste and an increased possibility of listeriosis.
Better quality bales are more expensive but this can be worth it in terms of feeding value if they are for feeding to store or finishing cattle. If you’re buying a large number of bales from the same batch it could be well worthwhile getting a sample analysed before agreeing a price.
Baled silage - safely gathered in – but what is their feeding value?
