Grass advice: If the grass account runs out your bank account will suffer
A welcome stretch in the evenings is helping to dry things up a bit. There has been a lot of rain and sleety showers this week, so ground became saturated fast.
The 10-day forecast is looking dry so we must get a plan in place to get cows out again full-time as soon as possible.
The spring rotation planner is useful to help us stretch out the remaining area left to graze, but I think the grass budget is even more important.
There are two accounts we need to focus on in spring; the business bank account and the grass bank account.
If the grass bank account runs out, the business account will suffer hugely.
Setting up a grass budget is very simple, and if you haven’t done so already you need the following:
- Grazing area hectares;
- Cow numbers – weekly;
- Grass allocations;
- Projected growth rates until at least May 1.
Managing Average Farm Cover
Once you have entered the above information, set grass allocation to full intakes (16-18kg DM per cow).
This will usually drop the Average Farm Cover (AFC) excessively (<350kg by ‘magic’ day) so we then go and start to reduce grass allocation to stretch out the AFC until the beginning of the second rotation.
As we are behind on the target area grazed to date, we will not supplement now but rather graze on for a few weeks to get a good proportion of the farm cleaned off and back growing at a reasonable level.
If growth rates are below what we have projected, we can see weeks in advance how fast the AFC is dropping and whether or not we need to adjust supplements to stretch out this feed.
Balancing growth rates and intakes
It is difficult to get a balance between maximising grass growth rates and keeping a predominantly grass diet from 21-30 days pre-breeding.
If we feed silage for a period greater than a few days within this 21-30 day pre-breeding period, it will negatively impact on first service conception rates.
Through knowing what your farm typically grows, you can set up a grass budget and then use weekly walks to see how this year’s growth compares.
The target farm cover by ‘magic’ day is circa 400kg (9-10 times daily demand, so this will vary between farms).
Set this as the target in your wedge for your farm’s typical ‘magic’ date (e.g. April 20) and if you have to increase supplements, do it hard and fast so that the deficit is corrected long before breeding begins.
Cows need to be on a rising plane of nutrition from now to the planned start of mating.
Monitoring cows Body Condition Score
Have you body condition scored (BCS) the herd to identify any under-conditioned cows?
A good time to BCS cows is after you come back from a discussion group meeting; having compared your herd to another, it will be easier to score the cows. Target BCS is 3.0 by May 1.
Slurry applications and grazed grass
Farms in the south will no longer follow grazed paddocks with slurry (unless you can apply some parlour washings straight after grazing).
Northern farms will continue to follow cows for another seven-to-10 days with slurry, as lower growth rates will allow this to happen.
Check soil sample results before applying, to make sure you are targeting deficiencies in Phosphorous/Potassium. If residuals are poor on some paddocks, do not apply any slurry or you will have no chance of cleaning out fully next time.
High yielding herds
For autumn/winter milk herds turning cows out to grass now, focus on reducing silage first of all and then bringing down concentrate levels when cows are out full-time.
Initially, in-parlour feeding rates should stay the same. If cows are getting meal in the wagon (e.g. 2-4kg), this can be pulled as soon as you stop feeding silage.
One area to be careful of is where cows are being turned out onto low grass covers and are receiving high levels of meal with finely-chopped silage – the lack of structured fibre becomes an issue.
Train cows on low pre-grazing covers (500-1000kg) and then increase pre-grazing covers, as silage is removed from the diet.
Spring grass has a high Neutral Detergent Fibre (NDF) percentage – usually 40-45%. Good silage will be 45-50% NDF, so the argument of feeding straw to cows because grass ‘has no fibre’ is hopefully now well put to bed!
If cows’ dung is very loose post-turnout, then you are either feeding too much meal or your meal is too high in highly-degradable ingredients such as maize.
Cows’ dung will become looser in the second rotation, owing to the lower grass Dry Matter, higher grass growth rates and lush, leafier grass.
Focus on quality protein ingredients
The average Crude Protein (CP) requirement of a dairy cow’s diet is 16%. With grass CP at 19-25%, this allows us to easily drop concentrate CP content to 14% when we have grass in the diet.
Focus on the quality of protein ingredients, rather than the protein percentage.
Soyabean meal and distillers’ grains are two excellent protein (and energy) sources. If some silage is to remain in the diet short-term, the 14% ration will still meet the cows’ protein requirements.