Hard to believe that we’re already a month into 2021. Been a nice change though, to have the cold dry days after all the rain at the end of last year.

Nevertheless, could just do with it warming up a bit now, so we can start to get some slurry on and grass growing. Hopefully a bit of slurry might deter the geese as well, as we’re having to go out to move them on from our grass reseeds a couple of times a day!

Last week NMR released its APR (Annual Production Report) for the year to Sept 2020, and we finally achieved a goal that has eluded us for the last few years, as we got our herd average combined milk solids above 1000kg. Although this is only around 4% higher than last year, we had been in the 940-960kg range for the last five or so years and were beginning to think that we’d reached some sort of limit.

So, what has changed in the last 18 months? Well firstly the herd as been getting a bit older lately as we’ve reduced our replacement rate from around 40% a few years ago down to only 20% last year.

This is partially a result of better genetics helping us to more robust longer lasting cows, but also in a large part a long-term consequence of using the mastitis vaccine, so we are now having to make fewer culling decisions as a result of severe cases of mastitis or high cell counts.

As cows tend to produce more milk solids with each consecutive lactation, as shown in the table, having more older cows will definitely have an effect in increasing average milk solids (See table below)

2018 2020

Heifers 790 860

2nd lact 990 950

3rd lact 1010 1060

4th+ lact 1080 1150

Average combined kg of butterfat and protein by 305 DIM

However, what is more noticeable is that pretty much across the board there seems to be an increase in milk solid production when we compare 2018 to 2020.

In order to explain what has happened, I first want to go back a couple of years to when Lactalis, who purchase our milk, introduced a banded incentive scheme whereby milk with %protein above 3.3 received an additional 0.2ppl. As our protein was generally around 3.25-3.27% we had a discussion with our nutritionist, Donald Lawson of Premier Nutrition, about possible ways to boost the protein level with a view to getting the premium.

The solution we came up with was to add Rumen Protected Methionine (RPM) to the mineral package given to the fresh and high yielding cows. Methionine is normally the most limiting of the amino acids in cows’ diets, and the literature showed that supplementation should increase both butterfat and protein levels.

Unfortunately, in our case these higher levels of milk solids seem to have been expressed as increased milk volume as opposed to increased constituent levels so, for the most part, we haven’t managed to get the protein premium. That said it did get us above our target of 1000kg of solids by 305 DIM so we can take that win.

But then to paraphrase the old saying goes 'milk solids in the tank is vanity; but money in the bank is sanity', so do the finances stack up for adding RPM to the diet? Well, the 50kg of extra milk solids equates to around 690 litres of extra milk (4%BF; 3.25%P) which would give an extra £150 in margin per cow after concentrate costs.

This is balanced against the daily cost of RPM of 12.2p/cow for the first 250 days of lactation which comes to a total of £30.50 per cow. Therefore, everything else being equal, we see a five-fold return on investment.

As we go forward with clear feed price increases on the horizon, especially with regards to protein, and little sign that the milk price will move up to compensate I think finding opportunities like this to optimise the cows’ performance will become increasingly important, as we seek to maintain margins.