MARKET COLD-STORAGE CHICKENS. 77 



made so to test each colony. It was soon found, however, that for 

 the available laboratory force the number of subcultures was becom- 

 ing unmanageable. Hence the search for anaerobes was restricted 

 more especially to those organisms causing putrefaction of proteid 

 in the sense of the German "Faulnisprodukte,"" which organisms 

 are generally of the spore-forming type, and which resist a tempera- 

 ture of 80° C. for ten minutes. 



Accordingly, after plating the suspension for (1) aerobes and facul- 

 tatives, and (2) anaerobes and facultatives, it was heated for ten 

 minutes to 80° C, and again plated according to Wright's method. 

 The colonies developing under these conditions were in such numbers 

 that their further study was possible. 



The chicken to be examined was placed on a clean metal dissecting 

 tray. An incision was made in the skin along the entire length of the 

 breast bone. With a small sharp knife, the fascia beneath was loosened 

 and the integument laid back, exposing the pectoralis muscle. By the 

 aid of sterile knives and scissors, a piece about one inch square was 

 removed from the upper portion of the Pectoralis major. Care was 

 exercised in the removal of this muscle not to contaminate the 

 fibers of the Pectoralis minor lying beneath it. 



As soon as the latter muscle was exposed several small pieces were 

 quickly taken from it and placed in the Erlenmeyer flask holding 

 broken glass. After reweighing, and so determining the weight of 

 the muscle excised, the physiological salt solution was added and 

 the flask shaken for ten minutes. Definite volumes of the physio- 

 logical salt solution were then transferred to petri plates, the desired 

 medium added, and the organisms evenly distributed by a rotary 

 motion of the plate, which was placed in the temperature at which 

 incubation was to take place. The period of this varied, of course, 

 with the degree of heat. Those plates developing at 37° C. required 

 but 2 or 3 days; those at 20° C. needed from three to seven days, 

 while the plates grown in cold storage, at —1.67° C, did not show 

 well developed colonies for several weeks, generally six to eight. 



EXAMINATION OF FRESH AND COLD-STORED CHICKENS. 



A study of the muscle from the breast, thigh, and walls of the 

 abdominal cavity, tested according to the plan described, yielded 

 sterile plates. Whether portions of flesh incubated in a nutrient 

 fluid would give a bacterial growth has not been determined for all 

 cases. Two experiments gave negative results. 



As indicated in the following table, the cold-stored chickens have 

 not been sterile. The thigh of Xo. 84 shows the greatest number 



a Rettger, Further Studies on Putrefaction, J. Biol. Chem., 1908, 4: 45. 



