Grass growth rates have plummeted on many farms and there are now a good few farmers in the midst of a serious grass deficit.

The forecast for the coming week is for the very high temperatures to continue for the week. This will do nothing for grass growth and some covers will probably go backwards.

The decisions on most farms is not whether or not supplement needs to be fed, rather how much and what.

I’m hearing some people talk about the drought continuing well into next month but there is no real basis to this, as scientific forecasters can only predict the weather for about seven days ahead.

The YR.no weather app is giving significant quantities of rain for early next week. The Met Éireann weather app shows some rain for Sunday night. It doesn’t forecast beyond Sunday 1 July at this time, so there is no reason to be overly pessimistic about the outlook and just manage the current situation on farms.

The main objective is to hold rotation length at 20 to 25 days. A 25-day round length on a 100-acre farm is grazing 4ac/day.

There are three or four main options for reducing demand. What to feed and how much of it to feed depends on each individual’s farm. When it comes to managing a drought, every farm is different.

Grazing silage ground

Grazing ground that was intended for second-cut silage is an option. Some farmers will zero graze this grass from outfarms. This is probably the cheapest supplement there is, but it could be an expensive supplement if the farm runs out of silage next winter.

One thing to keep in mind is that after a prolonged dry spell, grass growth increases. It usually compensates for the poor growth during the drought. So grazing some of the silage ground is an option.

Some grass fields are going to go backwards this week, so grazing them would be a better option than letting the grass wither away.

Feeding meals

This is the easiest option on the majority of farms. Feeding up to 5kg of meal is a simple option. It is expensive though as most dairy rations are costing in excess of €260/t.

In terms of reducing demand, it is only okay. There is always a trade-off between meal as a supplement and as a substitute. Meal acts like a substitute in spring and a supplement in autumn. Feeding 1kg of meal will not reduce the amount of grass eaten by 1kg, it is more likely to be 1:0.5 at the moment so you must restrict grass if you want to reduce demand.

The most amount of meal that should be fed is around 5kg/cow/day. Any more than this will increase the risk of stomach upsets in cows that are not used to being fed high levels of starch.

Feeding silage

Feeding silage is really only an option where silage quality is excellent, meal feeding is not practical or where more than 4kg or 5kg of feed is required. The problem with silage is that it is lower in energy and digestibility than grass and meal so cows won’t milk as well off it.

However, as a bulky feed it is excellent at reducing grass demand. Where to feed it is the next issue. Personally, I think feeding silage in the field that the cows are grazing is the best option but it depends on the numbers being fed. Feeding one or two round bales under the wire is a clean option and utilisation should be good in this weather.

A good-quality round bale of silage should have around 220kg of silage dry matter in it. One round bale in a 100-cow herd is 2.2kg of silage dry matter per cow, but there will be some utilisation losses when feeding out, whether at a feed face or in a field.

Feeding into a round feeder is an option, but the cows might be pushing and forcing at the feeder increasing the risk of injury or a hurt.

Feeding straights

Feeding straights such as soya hulls or palm kernel expeller is another option. These are concentrates that almost act like forages. They are low in protein but high in fibre and are a good supplement when forage is scarce.

Soya hulls is costing in excess of €220/t which doesn’t represent great value. Palm kernel at €190/t is better value. The nice thing about palm kernel is that cows regulate their own intakes. It is not very palatable so they won’t gorge on it.

Farmers in New Zealand feed PKE in portable troughs out in the paddock with ad lib access. The most amount of PKE that can be fed is around 6kg/head/day. Because it is not very palatable, some farmers in New Zealand will sprinkle molasses over it to get the cows to eat it starting off.

The most important thing is to do what is right for your farm. There are a lot of people talking about what their neighbours are feeding but soil type, stocking rate and average farm cover are different between farms.

Read more

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