Crude chitinolytic enzymes were prepared from the chyme, the mucous lining and the remaining tissue of the gizzard. Freezing and thawing of the sample did not affect their activity. The thermostability was variable, depending upon the source of the enzyme and the type of enzyme action. Under experimental conditions 165 mg N-acetylchitooligomers with high degree of polymerization could be obtained from a gizzard over 18 h.