28 August 1998

Toxin tests for whole-crops

CEREALS and whole-crop must be tested before feeding to ensure they do not contain high levels of a toxin causing poor performance in cattle and pigs.

Nutritionist Stephen Brooks warns that many cereal crops – about 60% – have suffered from fusarium this year, meaning incidence of toxin produced by some fusarium strains could be high.

Beware of feeding shrivelled grain as this can indicate an ear disease, such as fusarium, has affected the crop, he adds. Toxins will reduce feed intake and depress performance.

A MAFF-sponsored study of fusarium samples is underway to test for mycotoxins. But Mr Brooks advises producers, particularly those feeding home-grown cereals, to test each bin of grain for vomitoxin. A test costs about £25.

Despite low cereal prices, he warns against over-feeding cereals and urges producers to ensure all rations are well balanced

Mr Brooks advises limiting rolled wheat to 20% of ration dry matter or 4-5kg fresh weight as rolled and 7kg fresh weight as a combination of rolled and caustic treated wheat for dairy cows.

Whole-crop cereal silage must also be included in calculations for total cereal content of rations, while the maximum level of cereals fed should be reduced to take account of maize silage offered.

Increase proportion in rations slowly over a month, starting at 5% of ration dry matter. During this time, monitor feed intake, milk yield, dung consistency and milk fat results, he adds.