Optimising Feed Efficiency

by Martin Mulholland, Greenmount Campus, CAFRE

The average dairy herd in Northern Ireland is yielding 7000 litres per cow per year. Over the winter 60% of the cows yield less than 25 litres. These cows have lower response rates to concentrates than fresh calved, high yielding cows. On farms where there are adequate stocks of good quality silage, concentrate feeding to late lactation and lower yielding cows could be reduced by 30 to 90 tonnes over the next 3 months, especially on farms where diet feeder wagons are used. This is a saving in feed costs of £5,000 to £15,000. These savings can be made through a combination of grouping cows according to milk yield and / or adjusting feed allocation between the forage wagon and the milking parlour. At a time when returns from dairying are being squeezed, take the opportunity to reduce your costs of production.

Image 1. Total mixed ration feeding systems are an excellent method of feeding high yielding cows

What is your feeding strategy?

Are you feeding in parlour or out of parlour? Is your TMR partial or full TMR? Are you feeding a flat rate, feeding to yield, or feeding for peak yield? Are you grouping your cows? There is no shortage of different concentrate feeding strategies available. Hence it is not too surprising that confusion can arise and that the typical farmer over feeds, just to be sure!

Total mixed ration (TMR) feeding systems are an excellent method of feeding high yielding cows. Diet feeder wagons provide a consistent forage / concentrate mix, allow the mixing of forages, and provide the opportunity to feed high levels of concentrate. The accuracy of allocating silage and meal should allow greater feed efficiency. However, this does not appear to be the case on most Northern Ireland farms using feeder wagons.

Are you over feeding low yielding and under feeding your high yielding cows?

By their very nature, most dairy farmers try to feed their best cows right! The focus is placed on the fresh calved, high yielding cows in the herd. But how much attention is given to feeding the rest of the herd? The spread in daily milk yields of the typical autumn-winter calving Dairy Benchmarking farm, yielding 7000 litres per cow per year, is displayed in Figure 1 below. In January, 33 cows are yielding between 20-25 litres, while only 14 cows are yielding over 35 litres daily.

Figure 1. Spread of daily milk yield in a 7000-litre herd over the winter months.

The average daily milk yield works out at 23 litres per day over the winter with 60% of the herd yielding 25 litres or less as summarized in the Table 2 below. What is the spread of milk yields in your herd? Are you milk recording? Can you use milking parlour software to tell you?

Table 2. Typical spread of milk yields over the winter months in a 100 litre herd producing an annual yield of 7000 litres

Options to reduce diet costs

How can you allocate concentrates using a diet feeder wagon within your herd to avoid over feeding the lower yielding and late lactation and lower yielding cows? Some of the options include:

• Separate groups of low and high yielding cows;
• Reducing the quantity of concentrate feed through the diet feeder;
• Increasing the quantity of concentrate fed through the milking parlour to high yielding cows.

Table 3 shows the total winter feed use implications of three feeding strategies. These examples are based on an adequate supply of good quality silage (11.5 ME, 14% CP, 30% DM, Intake value 105) for a 100 cow 7000 litre dairy herd with the spread of milk yields as shown above. The rations in each example are formulated to provide the highest yielding cows in the herd the same concentrate allocation.

Where it is feasible to batch the cows into two groups, cows yielding below 20 litres can be fed in the parlour only. The higher yielding cows can be fed a partial TMR with 6.0 kg of meal in the wagon and topped up in the parlour to yield. The total concentrate use over a 6 month winter for this herd would be 105 tonnes.

However, the most common TMR feeding system used in practice is one batch of cows fed a partial TMR for the average yield. Good quality silage consumed at a dry matter intake (DMI) of 11.0 kg with 6.0 of a good quality meal through the wagon will support the average 23 litre yield. Most farmers feed a minimum level in the parlour to all (including low yielding) cows. A minimum feed of 1.0 kg per milking adds an extra 22 tonnes of feed over a 6 month winter. This feeding strategy would increase concentrate feed use over a 6-month winter by 53 tonnes.

On some farms the TMR ration for the whole herd is based on the requirements of the highest yielders in the herd. With the same silage, the top 10% of cows need 12 kg per day. The total 6 month concentrate feed use for the whole herd in this example would be 216 tonnes, an extra 111 tonnes.

Table 3. Implications of various feed strategies on the feed use for a 6-month winter

Optimise Feed Efficiency

Greenmount Dairy Benchmarking data indicates that feed efficiency has declined over recent years. Compared with the 2007-08 winter, the economic outlook for milk production is very different. In the expectation of high milk prices last winter, many dairy farmers were content to feed cows very generously. Cutting feed levels indiscriminately across the whole herd can lead to short and long term problems in terms of lower milk quality, impaired fertility and reduced milk output. However, on many farms there are options, as shown in this article, to more effectively target expensive concentrate feed to give the most economic response – fresh calved and high yielding cows. To improve your winter feed efficiency; contact your local CAFRE Dairying Development Adviser or Martin Mulholland on 028 9442 6750.

This article was first published in the January 2009 issue of United News. It has been reproduced here with the kind permission of the author Martin Mulholland. Martin Mulholland is a Senior Dairying Technologist with the College for Agriculture, Food and Rural Enterprise (CAFRE) based at the Greenmount Campus in Northern Ireland.

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