There are three classes of stock when it comes to feeding dairy cows for the winter. The first is the spring-calving cow in late lactation, the second is the dry cow calving in spring and the third is the freshly calved cow. The quantity and quality of the feed offered will vary depending on what animal is being fed.

Winter feed plans for this winter are different than normal because forage is scarce. While the last few weeks have been excellent for grass growth, fodder deficits still remain, particularly in the intensive dairy regions of the south and east. Even where enough silage is available, preserving stocks to build up a buffer for next year should be the objective. Therefore, reducing the amount of forage in the diet is important on all farms this winter.

Late lactation

Maintaining grass in the diet of the late-lactation cow for as long as possible reduces overall feed costs, increases milk yield and lactose percent and reduces the amount of silage being fed. However, grass should never be grazed in the autumn if it is at the expense of grass to be grazed in the spring. Unless the stocking rate is low and the over-winter growth is high, then grass grazed after mid-November is not worth it as you won’t have enough grass in early spring for freshly calved cows that need the grass more.

To know how much grass you can afford to graze in autumn you should do a grass budget for spring and autumn. Feeding 3kg or 4kg of meal with grass will extend the rotation length and grazing season. But cows should be on a 12-hour grass allocation and allocated a total diet of 15-16kg DM/day in late lactation. Otherwise, meal intake will go up but grass intake won’t change.

When cows come in off grass and are going to be milked on in the shed, the amount of concentrates being offered should depend on the quality of the silage and how much milk you expect to get from the cows. A bit like grazed grass, you don’t want to use up all the good-quality silage in the autumn at the expense of having good-quality silage for freshly calved cows in the spring. Effectively, when feeding spring-calving cows, having quality feed is more important in spring than it is in autumn.

In my view, feeding 3kg or 4kg of meal along with reasonable-quality silage to a late-lactation cow is an economic way of feeding her. The crude protein content of the meal should be around 18%, providing a dietary crude protein level of around 15-16%, but this presumes that the crude protein of the silage is high, at greater than 13%. Good-quality silage made from surplus bales is generally high in crude protein.

One of the biggest considerations when it comes to late lactation feeding should be body condition score (BCS). There is no point in stripping condition off cows in autumn to harvest more milk only to have to put it back on again in the dry period. How long to milk cows on for in late lactation depends on BCS and calving date. Later-calving cows in good BCS can be milked on for longer. Generally, mature cows will need to be dry for eight weeks while first-calving cows will need to be dry for 10 weeks.

After a difficult year, the temptation will be to milk cows on for longer this year, especially where silage is scarce and meal is to be fed anyway. I already hear some farmers questioning the wisdom of feeding meal to a dry cow when they could be feeding it to a milking cow. While there is no problem with this per se, the risk is that BCS will suffer and this will cause a lot more problems next spring.

Dry cows

Generally speaking an all-silage diet will provide the nutritional requirements of a dry cow for maintenance, BCS gain and the growth of the calf inside her. Table 1 outlines the supplementation required if silage quality is poor or BCS is low.

In a lot of cases this year, silage will be supplemented with meal, not because BCS is low or quality is poor, but because silage is scarce. The thing to remember when feeding meals to stretch silage is that the silage must be restricted. There is no point in feeding meal on top of silage if you don’t reduce the amount of silage being offered. Otherwise, the overall diet of the cows will increase and while BCS will improve you won’t have saved any more silage and will be left with a hefty meal bill.

So you need to work out how much silage you are feeding. If feeding round bale silage, weigh a sample of bales and get the silage analysed for dry matter. Really dry silage like haylage has a dry matter of over 40%. Reasonably dry bales are closer to 30% dry matter while typical first-cut pit silage has a dry matter content of about 20%. However, a lot of pit silage made this year will be higher in dry matter.

A typical round bale will have a dry matter content of about 180-220kg. If feeding 12kg of silage per cow this will feed between 15 and 18 cows for 24 hours. If feeding 10kg of silage and 2kg of fodder stretcher ration it will feed between 18 and 22 cows for 24 hours. If feeding pit silage you need to work out how much silage is in a grab. A typical 5ft shear grab holds about 200kg of silage.

You can work out how much silage a grab holds by measuring the size of a typical block in m3. Tine grabs will carry more silage than the internal dimensions of the grab because some silage sticks out. Divide the capacity by 1.3 to get to tonnes freshweight and then multiply by the dry matter percent to convert to tonnes of dry matter. Divide by 1,000 to get kg of dry matter.

Autumn calving

Feeding the autumn-calving cow over winter is a totally different ball game to feeding the spring-calving cow over winter. The nutritional requirements of this cow are totally different. To satisfy the energy and protein requirements of a freshly calved cow almost half the diet should be in the form of concentrates, with the other half coming from good quality forages.

The typical autumn-calving cow requires a dry matter intake in early lactation of about 20kg/day with an energy intake of about 0.95 to 1UFL/kg of dry matter fed. This should support a peak milk yield of between 30 and 40 litres per cow per day. The important thing when formulating such diets is to maintain balance between what the cow needs and what is provided in the forage. Less meal is required when forage quality is good.