Key facts:
| Herd Size | Target Yield | Fat% – Protein% |
| 540 | 7,000 litres – 630kgMS | 4.70% – 4.30% |
| Breed | Farm System | Calving Pattern |
| Crossbred | Grass, GS, MS + blend + parlour (in-shed) feed | Spring Calved – 10 weeks |
Issue: Low milk solids – Achieving <90% of liveweight in Milk Solids
Intro: This farm is well situated in a great grass growing area. It has a well setup feed pad and uses a mixer wagon for mixing feed and feedout. Historically milk solids per cow have been around the 80-90% of liveweight mark on this farm. The herd has lots of potential so a target of 120% of liveweight was set. Given the feed and feed systems in place this is a fair target as very many other farms achieve this.
Tracker Analysis:
If we look at the historic data, in the three years 2019, 2020 and 2021, a fairly consistent result was achieved. Following previous results was viewed as the norm and was delivering the same results..
The gap between the actual and predicted milk solids is now easier to see. There seem to be three main points where we see a drop off in production.
- Initial fall from peak – In mid to late October after the last of the cows have calved milk drops off rapidly.
- Mid lactation – Christmas in NZ is mid summer. This has had a negative effect on production with quite a step down.
- End of lactation – This shows cows being dried off early
Discussion:
Over the many hundreds of spring calved herds on Tracker we see a large amount having dramatic drops post peak. Whilst the fall on this herd isn’t dramatic it does represent the single biggest factor for the loss of milk over the lactation.
If we review the milk components against the Tracker predictions we can see some significant trends.
The left hand chart shows the milk fat%. The first thing to note is that the fat is higher than the prediction at the start of the season. This is generally an indication of fat mobilisation from the cows back directly into the milk. Whilst some fat mobilisation is useful to help the cows reach peak milk, excessive mobilisation can lead to fatty liver which reduces the livers ability to process glucose.
For this herd, the mobilisation of fat seems to be moderate, but still flags opportunities to look at dry cow management. If we could help cows achieve higher dry matter intakes and higher energy intakes in the first few days and weeks of lactation then the cows would mobilise less body fat reserves. Body fat reserves are useful to draw on during mating to assist embryo survival.
By the end of October the milk fat makes a serious departure from the prediction. At the same time the milk protein does the same. Both these factors indicate a significant shortfall in energy. Tracker can confirm this for us. The right hand panel of the Tracker Dashboard provides the key metrics for that week.
If we look at the third week in November, we can see that the calculated actual dry matter intake is a whole kilo of dry matter below the target for that week. If we were looking at that week on that week it would trigger us to look carefully at what might be limiting intakes and correct them ASAP! Even better, we would have seen at the start of the month that production had fallen off the tracks and we needed to get back on track.
Changes in the grass quality at that time often result in a drop in energy, especially fermentable energy that powers the rumen microbes. It is highly likely that at that time that we needed to supplement more starch and sugar to fire up the rumen to burn the ration hotter and extract more energy. In turn this would have created more microbial protein helping support more milk protein.
Ultimately Tracker prompts us to question the nutrition and management of the herd so we can act to resolve issues quickly.
Result:
The chart below shows the result that the farm achieved in the next year.
They did a great job in understanding what the shortfalls were and correcting them. Focussing on dry cow management, dry matter intake and energy supply. Consistently delivering to the cows needs resulted in a 21% increase in output from the same cow numbers and similar level of inputs.
I am sure they will build further on this and fill the remaining gap of 30,000kgMS worth $217,500 (£108,000).
