DairyCo

Forage for Knowledge update - 17 May 2011

Published 17 May 11

Growth rates are varying between 30 and 110 kg/DM/Ha/day with others in the 40's, 50's and 60's - this is purely an indication of those who have had good rain and those who are still dry.  Large parts of the country have had rain in the past week or so, but many haven't had enough and combining this with very dry soils, some of the growth rates are very disappointing. However, some aftermath growths have outstripped grazed grass growth rates and this is probably due to the coverage of crop shading the soil and reducing soil moisture losses. These aftermaths can come into the grazing round but as I have said before do not graze before two leaves, or preferably nearer, or at, three leaves.

Dry matters are consistently high ranging from 18 to 24%, another effect of the low rainfall. The plus side to the dry weather is that the dry matter intake potential of the grazing at the moment is high - if grass is available.

ME results are excellent with all samples between 12.7 and 12.9 compared to the same period last year of a range 11.9 to 12.6. This maybe a result of a drier spring this year compared to last, and as such better residuals in earlier rounds with the subsequent effect on quality now.

Crude protein levels are within the normal ranges, which you'd expect but there is a variation showing how important it is to have an idea of what proteins levels are.  This means that if supplementing grass you supplement with complimentary feeds so as not to overload the protein side of the nutrition.

Whether in a dry area or where reasonable rain has fallen, watch the leaf emergence rate as that will give you the answer to round length, back in at three leaves for quality and quantity.

Even though most of the country is experiencing low growth the challenge is to realise the potential of what you have. Our samples are showing an average of 12.8 ME; at 10kg/DM/cow that is 128/ME, minus 70 MJ ME for maintenance and that leaves 58 MJ ME. At a standard milk fat and protein that should give a shade under 11 litres, so get the most you can from the grass and save on the supplement/buffer.

If you are fortunate enough to have had the rain and the growth 15 kg DM will supply 192 MJ ME minus the 70 for maintenance leaves 122 MJ ME which is 23 litres, so there is still plenty of potential to make money from grass. The key to quantity and consistent quality is to watch the leaf appearance rate and feed grass at 2.5 to three leaves.