A lot of winter herds will be nearly finished calving by now.

Grass will soon disappear out of diets and thoughts will turn to the winter feed plan for these cows.

Given the 20% increase in concentrate costs over the last number of months, the conversation on a winter milk supplier’s lips at the moment is that of the stark increase in feed costs facing into the winter albeit with a higher milk price.

Concentrate feed is the largest variable cost for winter milk farms.

While average cost is around 6c/l to 6.5c/l, there is considerable variation around the average (4.5c/l to more than 12c/l) at farm level.

Fresh cow diets should promote high milk solids production and good body condition to improve fertility

Creating a winter feed plan that delivers the best economic return has always been well debated but never more than now. The plan needs to take into account available forage quality, herd milk yield and calving pattern (proportion of stale versus fresh cows).

Fresh cow diets should promote high milk solids production and good body condition to improve fertility, while ensuring stale cows are fed appropriately for their yield maximising feed efficiency at a whole herd level.

Should you feed more concentrate in a high milk price year?

While 1kg concentrate has enough UFl (the net energy value of a feedstuff) for 2kg milk on paper, this response to marginal feed is never seen in practice.

Feed responses appear better with low dry matter digestibility (DMD) silage, due to lower initial dry matter intake

Why? Extra concentrate reduces forage intake (substitution) and lowers whole diet digestibility (associative effect), so total UFL increase is less than the extra concentrate UFL fed.

The scale of this effect depends on cow type, days in milk, etc. Feed responses appear better with low dry matter digestibility (DMD) silage, due to lower initial dry matter intake (DMI), but total feed cost per litre will be higher.

For a given herd situation, breakeven concentrate feeding rate will not change too significantly due to a ±4c/l base milk price swing; milk response rate determines the economics to a greater extent.

What are the cow’s requirements?

When it comes to diet formulation, Table 1 outlines what the typical autumn calving cow requires at differing daily milk output levels.

A DMI of 20kg to 22.5kg is required to meet nutrient demand. Quality forage is essential; target at least 60% of DMI as forage (13kg to 14kg per day). Balance of DMI as concentrate.

High UFL energy per kilo promotes good milk solids and body condition

Energy is the first limiting nutrient for milk, diet UFL per kilo is constrained by the need for fibre in diet. Meet the target UFL per kg with high-quality forage and high-energy concentrates.

High UFL energy per kilo promotes good milk solids and body condition. Ensure you provide enough total PDI (protein) for target production. To maximise efficiency of energy and protein utilisation for milk production it is important to match the PDI and UFL ratio of the diet.

When the diet is balanced for protein fractions (PDIN and PDIE are similar) total crude protein level can be reduced to 15.5% (from the standard 17.5%) as a result, saving on feed cost. For example, a diet with 0.94UFL per kilo should have 94g to 97g PDI.

A total diet NDF (fibre) target of 30% to 36% will maintain rumen health and avoid acidosis, 24% to 28% should come from forage; silage DMD and intake achieved dictate overall diet NDF.

However, excess NDF (>40%) from poor forage sources or straw reduces DMI and milk yield. Use quality digestible fibre sources if forage intake/quality is limited.

Are you buying the correct quality ration?

Winter rations are often solely purchased on crude protein content where rather they should be bought on the basis of quality ingredients.

High crude protein rations are not necessarily better quality; high energy content is needed too. Excess protein is wasted if energy is lacking, but too low protein can reduce feed intake also.

Choose high energy (0.94+ UFL per kg as fed) rations, then pick the level of protein to suit the forage. As can be seen in Table 2, two rations with equal crude protein can have very different performance potential due to their energy (UFL) content.

Premium 18% contains many moderate-to-low UFL ingredients (soya hulls, maize gluten, sunflower, wheatfeed). Although the crude protein is 18%, the UFL value is only 0.89 per kg as feed. This is a poor-quality ration for milking cows. Super 18% uses good-quality ingredients in the main (barley, beet pulp, soya bean meal, maize, distillers).

The UFL value in this case is 0.97, making it a premium ration for milking cows.

The value of this milk is often greater than the difference in purchase cost between the rations

Super 18% would be expected to support an extra 220 to 260 litres of milk per tonne fed, depending on silage quality and feeding levels.

The value of this milk is often greater than the difference in purchase cost between the rations. This shows that feed quality cannot be decided based on crude protein content. Ensure when buying winter concentrates that they have a UFL value of 0.94 or greater per kg fed.

What level of concentrate does the diet require?

Firstly, make sure forage available on the farm is analysed through an approved laboratory and use the results accordingly. The benefits of higher DMD silage are well-proven; improved forage intake, more milk solids and milk from forage, better rumen health and lower concentrate feeding levels.

Milk output

Table 3 outlines the concentrate feeding levels required for different levels of milk output depending on the silage quality available.

For example, the typical 600kg cow will require 7.5kg of concentrate to produce 30kg of milk whereas that requirement would be 10.0kg should the silage be 65 DMD.

Typically, every five-unit drop in DMD will need 1kg to1.5kg extra concentrates to compensate for the lower energy level.

Where silage quality is poor, forage intake levels will reduce, therefore it’s important to monitor NDF levels in the diet and where shortfalls are identified extra fibre sources should be fed.

There are significant challenges in meeting energy requirements in these situations.

What about the relative value of alternative feeds?

Farmers should not only weigh up the relative value of the feed but also the labour and fixed costs attached to feed-out before deciding to purchase alternative feeds.

The labour and fixed costs that shall be incurred are often discounted at farm level.

Table 4 outlines the value of feedstuffs when compared to barley and soya at €270/t and €420/t, respectively.

All wet feeds and forages must be discounted to allow for losses, reducing the relative value by the same percentage.

Assuming silages (maize and whole crop) are ensiled, losses of 10% should be discounted from the table above. Feeds such as brewers’ grains should be discounted by 10%, while fodder beet should be discounted by 15% to allow for tare losses and additional labour.

Analyse performance for your herd feed plan

Farmers should check the milk yield distribution for their own herd using winter milk recording data before setting their feeding strategy for the coming winter.

Following analysis of milk recording data for a high-yielding herd (8,000kg) with 40% of the herd calving in the autumn.

The yield distribution for every cow in the herd in January and February was plotted on a graph with yields ranging from 15kg/day to 43kg/day.

The average yield for the herd was 27kg.

This high-yielding herd has 9% of cows over 35kg.

Therefore, 86% of daily milk output comes from the standard base cow within the herd.

The strategy to ensure the best economic return should be to ensure the basis of the diet is formulated to a herd level and not that of the “best” cows based on the herd’s own performance. Individual high-yielders can be managed as sub group thereafter.

What about the Johnstown Castle winter milk diet?

For the Johnstown Castle winter milk herd, the aim is to have a good-quality base diet that will work well for high-yielding and lower-yielding groups alike. This simplifies feeding in the yard.

The parlour is used to top up the high-yielding group with additional concentrate. The feed ingredients used for the basic milking diet are:

  • 9kg DM of good-quality grass silage (74% DMD).
  • 5kg DM of high-quality maize silage (33% starch).
  • 3kg of a high protein (23% crude protein) coarse blend fed as part of the forage mix (this contains barley, soya bean, beet pulp and distillers’ grains).
  • This diet provides enough nutrients for approximately 20kg high solids milk as a base level.

    Lower-yielding cows receive a further 2kg parlour ration. Fresh cows receive up to 6kg additional parlour concentrate bringing their daily dry matter intake to 21.5kg on average. This covers the fresh group with enough energy and protein for a group average milk yield of 31.5kg, which is our target for December/January.

    Parlour concentrate

    Parlour concentrate is formulated for high energy at 18% crude protein equivalent and contains full minerals and vitamins.