Early Grazing in Cornwall March 2000

On high forage diets, supplemented with up to 6-8kg concs two hours grazing can increase yield by 2.5L protein by 0.1% and reduce silage by 25%.  In high yielding herds, on hi maize rations the effect can be less or even detrimental to the high group, but is appropriate for mid - late lactation cows fed large amounts of silage or where the overall palatability of the forages is not high.

Fundamentals

        Tracks key is good access to the fields, so if no good tracks - don't early graze.  Nothing worse than cows walking trough swampy conditions, mud up to the udders and the mud and stones forming a grinding / puncturing paste

        Donít Over Graze Grass is not growing fast enough to meet demand for full bore grazing, even though there is a reserve of 1-1.5t per acre, silage supplementation is vital.  This means that cows must be held back.  What we are doing is eating into a reserve of grass.

       NEVER eat the grass down hard by milkers as regrowths will be excessively slow - no leaf - no photosynthesis - no growth, and milk or body condition will suffer.  Graze from 6-8" down to 2". If the high group is not grazed, then the lows can spend longer outside as they have a larger area.

       Hungry Cows - cows should be aggressive grazers so make sure the silage has run out a couple of hours before grazing.   This is not suitable for the high 10-12kg maize fed group that we want to get in calf.

       Back-fence to ensure cows are only on an area for one grazing. Sward damage, if it occurs, will then be restricted to a small area and regrowths superior.

      Staggers or low Magnesium status:  Grass takes up potash steadily over the winter.  A slurried sward, one receiving a full silage compound dressing, or soil analysis is high (2+) grass potash levels will be very high  > 3% K and proteins typically well over 20% CP.  Even in low yield groups at full graze staggers can arise. Total dietary levels up to 0.5% Magnesium may be required.  In any case add 75-150g Cal Mag to the silage for the low group but with due regard for other magnesium sources and the amount of grazings offered.

      Reseeds: are not for early grazing unless sufficiently compacted by grazed sheep or summer drilled and grazed late summer / early Autumn 99.  If there is excess growth, strip grazing when dry and hard is best.  The first season's growth is easy to graze down, as there is minimal lignfication of the stem.  I much prefer Autumn Reseeds to be taken as silage.