There is sufficient quality grass available to feed calved cows from next February through to the commencement of the second grazing rotation in early April, and that
Every cow calves down with the optimal Body Condition Score (BCS),i.e. BCS 3.25 to 3.5.
The time to set the correct foundation to achieve these key targets is right now, and a “ten day” delay in the current decision making process will probably make the difference between failure and success.
Whether we realize it or not, grass growth is nose-diving towards an almost stand-still position in late November.
Decades of data on grass-growth rates for the late November to early February period shows that very little grass grows on most farms. In some winters, on some dairy farms, there is no growth in the grass carpet from housing time in late autumn to let-out in early spring.
Therefore, if you want to have grass in spring, you must carry the optimum amount for your farm through the winter from this autumn.
Financially, it is calculated that each extra day a milking cow is at grass full-time in spring is worth €2.70 (€945/week for 50 cows), and is nearly twice as valuable as the benefit gained from grazing in the autumn period.
On average-stocked dairy farm platforms (2.5 cows/ha) with reasonably compact spring-calving (> 75pc calving in the first six-weeks), the Average Farm closing cover (as measured on the 1st of December)should be at least 600Kg DM/ha.
On higher stocked dairy farms with highly compact spring calving and/or with a portion of autumn calvers, the closing cover could arguably be as high as 700kg DM/ha.
In order to achieve these target closing covers, then the area available for grazing in the first rotation in spring would have to be closed sequentially, following grazing from early October. Furthermore, 60% to 70% of the area should be grazed out by the first week of November.
It goes without saying that every paddock should be targeted to achieve a good clean-out (grazed down to 4cm), with the dung pat areas grazed out (allowing maximum tillering to take place in the dormant period, leading to enhanced grass growth the following year).
The spring-calving dairy cows milk production mechanism must be closed down overwinter for renewal to prepare for the next lactation. Essentially, there can be no compromise on managing her to achieve the correct body condition score at calving.
A mature cow needs at least eight full weeks of a dry period and first-calvers needs 10 weeks or more dry (she is still growing and maturing).
During a normal dry period, when cows are fed ad-lib on well preserved silage of 68 to 70 Dry Matter Digestibility (DMD), they will gain 0.5of a BCS or thereabouts. Unless these cows are dried off on time at a BCS of 2.75 or greater, they won’t reach the target calving BCS of 3.25.
Of course, they can be fed concentrates in the dry period, but this requires extra cost, inconvenience and a careful management strategy which often fails or brings additional problems such as difficult calvings or compromised cow-health.
A tried and trusted management tool is to dry the thin and vulnerable cows a little earlier.
Ideally, in October, all cows should be put carefully through the crush and their individual BCS determined and recorded. As with the management of grass, by measuring and recording cow BCS, corrective management decisions can be made on time to achieve the calving BCS target for every cow (and they all count).
The clock is already ticking and counting down to spring, but it is not too late yet to alter the path towards getting grass and cow body condition right for spring.
Relook at your grass closing plan, and revise it if necessary and put a sensible plan in place for drying off your cows. Remember an adjustment of “ten days” or more at this stage could make the difference between an average and a highly successful outcome on your farm next spring and for the Dairy year of 2019.
Tom Murphy, is a Teagasc Adviser in Galway/Clare