[Results of comparative studies on ammoniated straw pellets conducted in two research institutions of animal nutrition].

Ammoniated straw pellets were produced from pure wheat straw in a pelleting press reaching temperatures of more than 90 degrees C, 4% NH4HCO3 being added as degradation agent. Digestibility trials with sheep gave 389 energetic feed equivalents (cattle) per kg straw dry matter. This value exactly agrees with the formula Energetic feed equivalents (cattle)/kg DM = 650 -6x x = % crude fibre in dry matter which had been reported first in 1973 by Bergner and Marienburg (Arch. Tierernährung 23, 423 [193]) for chemically treated straw pellets. When testing the digestibility of the same straw pellets charge in the Animal Nutrition Division of the Dummerstorf-Rostock Research Centre for Livestock Production, considerably lower values were found which would allow to calculate energy concentration to amount to 310 energetic feed equivalents (cattle)/kg DM (see Arch. Tierernährung Vol. 28, page 393). The reason for this 20% lower feed value of the straws pellets lies possibly in the reversibility of the degradation effect when using ammoniacal media. The digestibility of the straw pellets had been tested in the Berlin research Institution one year earlier than at the Rostock Institute. The possible causes of the reversibility of the ammoniacal degradation effect are discussed.