After another week of wet and overcast skies, growing and grazing conditions continue to deteriorate across the country – and the prognosis for the coming week is no better. While a drop in cow performance is expected, it is noticeable that the recent decline is accelerated over the past 10 days. In general sward quality is improving across farms as the ratio of leaf to stem increases. However energy levels in the grass is low due to the lack of sunlight, and with obvious intake limitations of low dry matter grass on the wet days, these factors are conspiring to reduce yield and milk solids yield.
At this time of year crude protein levels in grazed grass are high and not limiting. What is needed is an increase in energy intake which is possible with concentrate supplementation. Year to date, I have questioned the profitability of concentrate inputs given the low milk price especially in an adequate grass supply situation – and this view has not changed. However, with the recent current drop in feeding value of grazed grass, an associated response in yield and solids output is more likely. Probably the best options are citrus pulp or rolled barley – two high energy feeds available at low cost. Once cow performance has recovered, coupled with improved weather conditions, then the concentrate can be phased out again.
I have recently heard reports of grass tetany in herds. With day and night temperatures to lower by the end of this week, it is advisable to re-introduce Cal Mag into the diet until grazing and weather conditions improve.
It is also quiet noticeable that cow body condition score has improved across farms with current farm averages ranging from 2.85 to 3.10. The level that individual farms are at is mostly dependent on cow type and % of Holstein blood. Whatever level you are at, what is important is that body condition is increasing on your farm. If not, then watch out for other symptoms of ill thrift, runny noises, coughing, dry hairy coats etc – if present then veterinary intervention may be necessary.
Growth in the past week has seen a decline form the previous week but ranged from mid 40’s to mid 60’s kgDM/ha/day – with many soils waterlogged or saturated at least, with the suggested drop in air and soil temperatures, growth can be expected to slow further for the coming week. In this regard, it is essential that you are now on an extended rotation length – circa 30 days by early September – allowing for a longer time for paddocks to recover between grazings and for the further building of grass supply. Plan to further increase rotation length up to 35 days over the next two weeks.
