FARMERS feeding a 50/50 mix of maize and grass silage face an extra feed cost of £34 a cow this winter.

Nutrition specialists Frank Wright said the wet weather has scuppered the feed value of this year's maize crop.

Tests on the first 400 samples of mainly early cut maize show that dry matter, protein, ME and starch are all down on last year.

The average results so far show dry matter at 27.7pc, protein 8.1pc, ME 11.3 and starch 27.1pc. When combined with the significant drop in grass silage quality, extra supplementary feed will be needed to compensate for the fall in quality.

The company has used the dairy industry's new equation for working out silage intakes and compound feed requirements. It predicts the dairy cow will, each day, need an extra 3kg of maize silage, 1kg grass silage and 0.25 kg of quality 13 MR compound to maintain a production of 30 litres if fed on an average quality silage mix. It represents an extra silage cost of £16/cow and extra cake cost of £7/cow.

Protein should also be increased by 2pc to compensate for the shortfall in average silage quality, at a cost of £11/cow.

The outcome is an extra cost of £34 per cow over a 200-day winter when fed average 2000 season maize and silage