Finding the appropriate farm stocking rate is crucial in order to take full advantage of your cow’s genetic potential, grow and utilise as much grass as possible, and run a profitable dairy enterprise.
This was the topic of discussion at a recent joint signpost programme held by Teagasc and Dairygold at a farm walk held on the farm of Tom O’Connell in Gurteen, Co. Cork.
The clamping down on regulations in the dairy industry from the prospect of a further change in derogation, the nitrates banding, and the new fertiliser database, have all coincided to squeeze the life out of farmers.
With struggling grass growth rates, unpredictable weather conditions and tough springs being prevalent issues, it has never been more important to know what optimal stocking rate you should be running on your farm.
Farm performance
O’Connell’s herd produced just under 500kg/milk solids last year on a milking platform of 2.3 cows/ha and a whole farm stocking rate of 3.3 cows/ha.
This year, however he is hoping for better cow performance as he tries to unlock the herd’s genetic potential by farming at an optimal stocking rate.
The cows’ milk yield last year was 5,499L/cow at 3.82% milk protein and milk fat at 4.79% with a somatic cell count (SCC) of 178,000 cells, while feeding 1,217kg of meal/cow.
In 2023, O’Connell spread 164kg nitrogen (N)/ha across the whole farm with an N balance of 161kg/ha and nitrogen use efficiency (NUE) of 29%.
The herd’s economic breeding index (EBI) is €240 with the milk sub-index at €69 and the fertility sub-index at €111.
O’Connell’s land has great soil fertility, with 92% of the farm having a pH of over 6.2, 99% of the farm being in index three and four for phosphorus (P) and 86% of the farm is index three or four for potassium (K).
Appropriate stocking rate
He is currently stocked at 2.3 cows/ha on the whole farm and 3.3 cows/ha on the milking platform, which has not improved the performance of the herd, as poor weather conditions and grass growth have hindered that.
O’Connell is milking 320 cows and grows about 14.5t DM/ha, is constantly reseeding, has optimal soil fertility and has 60% of the farm incorporated in clover.
He was traditionally constantly growing 15t DM/ha but that been a struggle over the last number of year. This was put down to poor growing conditions and is the reason O’Connell feels he has to reduce his stocking rate even further.
In order to do this, O’Connell feels he has to reduce his cow number by a further 10 cows to have a whole farm stocking rate of 2.2 cows/ha.
The farmer sets a high demand of 20kg/DM/cow to try and fulfil the herd’s potential of 550kg of milk solids.
On the day, there was a chart presented, which predicted how much extra silage you need to produce a certain amount milk solids/cow according to the farm stocking rate.
It was based around O’Connell’s system growing around 14t DM/ha, while feeding 1t of ration and showed attendees how much extra bales of high quality will be needed at certain stocking rates to achieve a certain amount of solids.
The amount of extra bales required is as follows:
480kg MS/cow 500kg MS/cow 520kg MS/cow 550kg MS/cow 3.0 cows/ha -2 -1.5 -1 0 3.2 cows/ha -1 -0.5 0.3 1.2 3.4 cows/ha 0 1 1.4 2.4 3.6 cows/ha 1 2 2.4 3.4 3.8 cows/ha 2 3 3.5 4.2
Teagasc’s Nora O’Donavan, told Agriland that O’Connell starts calving on January 25, with half of the herd calved by February 8.
“Tom has such a good compact calving system, with the majority of the cows coming into their peak in April where grass growth rates are only around 30kg DM/ha.
“If he pulls his calving start date back by a week later, there will be less cows at peak milk before grass growth is matching demand,” O’Donovan said.
The problem for O’Connell, is that during April, he takes out paddocks for reseeding meaning he could be heavily stocked 4 cows/ha during this period when cows are reaching their peak.
O’Donovan went on to say that “recent studies show that the modern genetics of cows have shown to have a higher intake requirement early in the season”.
O’Donovan claimed that the farm’s out-blocks are performing very well, with good grass growth rates and the blocks are able to contract rear extra heifers.
The out-blocks seem to be performing as well as the milking platform, which is a rare achievement. Many farmers tend to neglect the soil fertility and growth performance of their out-blocks.
The performance of these out-blocks ensures silage reserves for O’Connell, as he ended up with extra silage in the yard at the start of spring this year.
O’Donovan advised farmers who need to add extra storage to “consider reducing their number before investing”.
“I would pull my cows back before investing, because once you’ve invested, you’re tied into it,” he added.