Table 1. -Results of CF tests following four different serum treatments 



Source 



Treatment 



Positive 



CF test results 



Negative 



Suspect 



No test 



Known Positive Animal 



Known Negative Animal 



r Phenol 



Refrigeration .... 



Refrig. and Phenol 

 ^ Freezing 



Phenol 



Refrigeration 



Refrig. and Phenol 

 ^ Freezing 



248 











2 



248 











2 



249 







1 







250 



















8 



241 



1 







3 



248 



3 







■ 7 



243 











6 



244 







Table 2.-CF titers of known positive serum subsamples following specified treatments for preservation 



Treatment 



20 or less 



40 



Titer' 



80 160 



320 



640 



(A) Refrigeration 2 6 4] 69 



(B) Refrig. and Phenol 9 61 82 



(C) Phenol (Standard) 52 70 71 



(D) Freezing 20 85 64 



Titer expressed as reciprocal of serum dilution giving 4+ reaction. 



Titration results for 22 of the 250 subsamples were invalid because of mechanical error. 



74 



32 



6 



72 



23 



3 



47 



9 



1 



66 



11 



4 



Titers following the different treatments were compared using the X test. Calculated X 2 values for the 

 comparisons are presented in table 3. Each of the three experimental treatments (A, B and D) resulted in titers 

 significantly higher than the standard phenol treatment (C). Also, titers following treatments A and B were 

 significantly higher than titers following treatment D. The least difference detected was between treatments A 

 andB. 



Table 3. — Calculated X values on comparison of titers between 



treatments 1 





Treatment 



comparison 



X value 



P 2 



A vs C . . 







65.71 



<0.005 



B vs C 







44.10 



<0.005 



D vs C . . 







21.23 



<0.005 



A vs B 







7.04 



<D.25 



A vs D . . 







32.12 



<D.005 



B vsD 







14.84 



<0.025 



A = Refrigeration. 



B = Refrigeration for 5 days followed by adding phenoL 



C = Phenol. 



D = Freezing. 



P = 0.05 or less was considered significant. 



