14 



CONTROL SERIES No. 63 



Table 4 — The 1 



NCIDENCE OF 



Jellied Samples for Blood Collectors in 1930 

 AND IN 1931 



Discussion 



The jellying of blood samples was found to occur with great irregularity. 

 Observations limited to the collection of blood samples from a small number of 

 laboratory birds suggested several possible contributing factors. A chemical 

 investigation of jellied samples was not undertaken. The relationship of feed 

 to jellying was not studied. The effect of the physical condition of birds, at the 

 time of collection of blood, upon jellying was not studied to any great extent. 

 Blood samples from a few laboratory birds which were in a somewhat weakened 

 condition showed a slight tendency to jelly consistently. No healthy individuals 

 appeared to be constant offenders. The extent to which the character and size 

 of the incision may contribute to jellying was not investigated extensively, al- 

 though they appeared to have some influence. Less jellying was noted in blood 

 samples from chickens than in those from pigeons, pheasants, and guinea fowls. 

 This difference may be associated with the character and size of the incision. 

 The rate of flow of blood from the incised vein is much slower for chickens in 

 general. To what extent generic characteristics may be a contributing factor 

 was not determined. 



In the routine collection of blood samples, it appeared that the temperature 

 at the time of collection of samples and the method of handling after collection 

 are important factors. The three methods of applying heat to blood samples, 

 by placing in blood collector's pockets, by using a hot water heater, and by using 

 an electrically heated water bath, assisted in reducing the number of jellied sam- 

 ples. The amount of blood collected had a slight influence on the number of jel- 

 lied samples, there being less jellying of the larger samples. The difference, how- 

 ever, was not as marked as in the case of the application of heat to the blood sam- 

 ples. Holding blood samples over night at room temperature or placing them in 

 an incubator for one hour at 35° C. reduced the number of jellied samples. Vary- 

 ing degrees of hemolysis occurred in the samples held over night at room tern- 



