that of the previous season. The reactors were confined to one flock which was 

 heavily infected. Eighteen flocks were found to be non-reacting. 



The results for the flocks tested for two consecutive years reveal a considerable 

 increase over the previous season in the number of flocks and birds tested A 

 total of 62 flocks, representing 85,638 birds, was tested. The percentage of in- 

 fection was 0.25. The reactors were confined to three flocks. A total of 59 

 flocks, representing 82,193 birds, was non-reacting. 



In the group tested for three or more years, 224 flocks representing 510 727 

 birds were tested. The percentage of reactors was 0.24 which is the lowest for 

 all groups. A total of 216 non-reacting flocks, representing 481,826 birds was 

 detected in this group. Only eight positive flocks were identified. The majority 

 of reactors detected in this group was found in one flock. 



Considering the four groups as a whole, 295 flocks, representing 583,733 birds 

 or 91 percent of the total birds tested, were 100 percent tested and non-reacting 

 t IS encouraging to note that such a high percentage of the birds tested are in 

 100 percent tested non-reacting flocks. However, one should not ignore the 

 number of birds (37,059) in infected flocks nor the average percentage of infec- 

 tion (8.4) for those flocks. It should be indicated that the bulk of this infection 

 was limited to a few flocks. It is hoped that these heavily infected flocks will be 

 replaced by pullorum clean stock. 



T.ABLE 2. Annu.^l Testing Versus Single and Intermittent Testing 



The results in Table 2 indicate that flocks with two or more years of testing 

 are apt to have a lower incidence of infected flocks as well as a lower percentage 

 of reactors. Annual testing along with sound eradication and prevention meas- 

 ures IS certain to produce successful results in establishing and maintaining 

 pullorum-free flocks. It is unfortunate that some flock owners are unable or 

 unwilling to follow a program of this sort. 



Appearance of Infection in Flocks Previously Negative 



Table 3 gives the testing results for flocks which had been non-reacting for 

 one or more years but showed infection in 1942-43. Thirteen "breaks" are 

 listed and in only two instances was the amount of infection above one percent. 



