18 August 1995

Now corn-cracking on whole-crop too

CORN-cracking is now an accepted part of maize silaging, with most modern forage harvesters now able to offer this service. But using such equipment when harvesting whole-crop wheat must count as a relatively new development.

The University of Readings Centre of Dairy Research (CEDAR) is currently evaluating the benefits of employing corn- crackers when harvesting high dry matter whole-crop.

Using a Claas Jaguar 840 self-propelled forager, two samples were harvested from a crop of Hussar at about 60%DM – one with the corn-cracker engaged and set to a 1mm gap so the surface of the grain was just cracked, while the other sample was harvested conventionally.

Both samples have been clamped separately and treated with 40kg urea/t DM.

Silage ration plans

Plans are to feed the silage in a ration of one part grass to two parts whole-crop, with a fixed amount of concentrate to different groups of cows which will be monitored for intake and milk yield.

Trials by CEDAR over the past three years have shown that replacing half or more of the grass silage input of a dairy cows diet with urea treated whole-crop results in small improvements in yield and milk quality. An increase in whole-crop dry matter content however, reduces the amount of starch digested with the result that ME can drop from 10 to around eight in a crop harvested at 60%DM.

Use of the corn-cracker in high DM crops could, it is hoped, enable the full benefit of the crop to be utilised.

Use of a forage harvesters corn-cracker for whole-crop wheat could result in better utilisation of the crop. Trials are under way at the University of Reading Centre of Dairy Research to substantiate claims of improved starch digestion. Inset:Grains on the left have been cracked sufficiently to break the surface of the grain.