Rethink heifer grazing strategies to achieve higher performance and reduce costs
Following a challenging, late spring and now short or no supply of forage and straw stocks on many farms, grazing your youngstock is a sure-fire way to reduce costs and improve performance.
Grazing youngstock, however, isn’t quite as easy as opening the gates and letting them go. Careful consideration of stocking rates and rotational grazing will increase the performance and productivity of the land, leading to greater Dry Matter (DM)/ha.
If grazing is well managed, you should be able to achieve 0.8-1kg DLWG through the summer period for most heifers. Any animal from four months of age upwards can benefit from grazing through increased performance and reduced rearing costs.
Getting stocking rates right in the early season is key to maintaining grass quality throughout. Grass growth peaks between late April and May – this is when its quality is at its best and early turnout is always best in order to take advantage of this. Although this year has been challenging, it’s important to turn your stock out as early as grazing conditions allow. Calves and heifers should grow with the grass, they should not be turned out into high grass covers as this will lose its quality later in the season.
Having higher stocking rates throughout April and May will allow more of the youngstock’s allocated grazing platform to be available for making first cut silage. This means an increase in the tonnes of DM/ha grown. The suggested stocking rates based on cattle weights can be found in Table 1, below. Use these figures to base your heifer grazing platform on.
By adopting a paddock grazing method for heifers, you will produce more tonnes of DM/ha, whilst simultaneously achieving higher DLWG and kg of growth/ha. The grass allocation can be easily managed by matching grass supply to demand – using a platemeter is key to knowing your grass availability and covers. The estimated DMI/day for heifers grazed using a paddock system can be found below, in Table 2.
Pre-grazing covers should be targeted at 2800-3000 kg/ha, with post-grazing covers targeted at 1,500-1,600kg/ha (as seen in Table 3). It is crucial to get the post-grazing residuals down in order to maintain grass quality later into the season and to allow the land to achieve its growth potentials.
When paddock grazing youngstock, it is advised to set up paddocks for 3-7 day periods. Shorter breaks work best and allow you to run a shorter rotation, but, this is all dependant on the management and numbers used to justify paddock sizes.
Daily Allocation of
Grass: Working out your own requirements
The length of rotations changes in accordance with grass growth, areas of surplus grass need to be identified and removed to produce silage. Through adopting short and regular grazing blocks, it is much less likely that unpalatable grazing areas will develop during the season. You must however, bear in mind the DMI of concentrates if they too are being fed.
Feeding at Grass
Supplementary concentrate feeding is only required in some circumstances during the grazing season, these include:
Grazing calves <6months of age – require supplementation of 1-2kg concentrates
Anything <12 month of age – supplementary feeding is only required for the first four weeks, if grass quality and availability is good then supplementary feeding can be stopped
Anything >12 months of age – no need for concentrates
September onwards for stock <12 months of age – dependent on grass quality
Wynnstay offer a specially formulated Heifer Grazer 16 + Biosprint nut, formulated to complement grazed grass. The nut is made with lower protein and balanced starch/fibre to make the most of grass in a young ruminant.
For heifers that aren’t fed any concentrates at grass, some form of mineral supplementation is required in either bolus or block form.