As we head into a wet winter, here are five top tips to make the most of brassicas while minimising environmental risk.
1. Introduce brassicas slowly
Introduce stock to brassica gradually on full stomachs to avoid digestive upsets. Start with two hours a day, gradually increasing over seven to ten days to unrestricted access.
2. Provide a run-back and provide protection
A wide-access run-back should have been factored in when the crop was drilled. This could be the grass headland or access to an adjoining field. Run-backs are essential for animal welfare and crop utilisation. Also, always provide shelter, such as a hedge or area they can get out of the wind.
3. Strip grazing
Long, narrow breaks are best to enable all stock to access the crop at the same time and prevent localised poaching. The fence should be moved daily.
Start strip grazing at the top of the hill and work your way down to reduce run-off and environmental risk.
Double fencing is also advisable. A fence at the feed face can be looped around one end of the field in a U and used to make a second fence line behind.
When stock is moved, the first fence line can simply be wound up. This eases stock movement.
4. Feed plenty of fibre
Brassicas are generally low in dry matter at about 12-15% DM so fibre needs to be provided to provide scratch factor and promote rumen function. Fibre should make up about 20% of intakes.
Straw will be adequate for dry cows, whilst better quality silage will be needed for growing animals. Bales should be put out ahead of grazing.
Avoid driving tractors onto the field during the winter to limit poaching. Always provide drinking water.
5. Provide appropriate minerals
Brassicas tend to be high in glucosinolates, which can negatively affect iodine and vitamin E uptake. They are also low in copper, iodine, phosphorous and magnesium so it’s important to provide these minerals.
Bolusing every animal is advisable to ensure they get the right dose. A mineral bag can also be cut open over the top of a silage or straw bale to provide minerals with every bite.
Brassica seed: Growers' guide