A Chick Growth Factor in Cow Manure

Abstract

Soybean oil meal fed to young chickens as 70% of the diet caused an inhibition of growth and increased mortality. Both of these effects were counteracted by the addition of the growth factor of cow manure to the diet but not by the addition of methionine. The growth factor of cow manure improved the nutritional value of a chick diet containing raw soybean oil meal as the only protein concentrate, but not to the extent that it improved a diet containing heated soybean oil meal. Evidence has been presented that soybean oil meal at high leve's exerts an inhibiting effect on the growth of chicks which is not due to a heat-labile trypsin inhibitor, which is not nullified by heating or by enzymatic digestion, but which is counteracted by the chick growth factor of cow manure.