In the group tested for two consectutive years, the number of flocks and tests 

 was markedly smaller than in the previous season. The flocks numbered 33, 

 representing 44,560 tests of which 0.16 percent were positive. Thirty-one non- 

 reacting flocks, representing 41,651 birds, were identified. 



The group tested for three or more consecutive years showed a definite increase 

 over the previous season, 256 flocks, representing 601,536 samples, being tested. 

 The percentage of positive tests was only 0.05. A total of 247 non-reacting flocks, 

 containing 549,248 birds, was detected. 



Considering the four groups as a whole, 413 flocks were tested, representing 

 762,066 birds and 791,596 samples, of which only 0.11 percent were found to be 

 positive. The 354 flocks which were 100 percent tested and non-reacting con- 

 tained 692,556 birds, or 90.8 percent of all birds tested. These results are indeed 

 encouraging, because the larger the number of birds in 100 percent non-reacting 

 flocks, the more rapid will be the progress in establishing additional puUorum- 

 free flocks. Massachusetts flock owners should have ample opportunity to buy 

 good stock which is free of puUorum disease. 



The number of positive flocks was 27, representing 40,837 birds. Although 

 this is a slight increase over the previous season, it is not significant when one 

 considers the over-all increase in the total number of birds tested. It is hoped 

 that these infected flocks will be disposed of and replaced with puUorum-free stock 

 this year. 



The results indicate that flocks which are tested annually show a lower incidence 

 of reactors than do flocks tested for the first time or intermittently. Annual 

 testing is the only way to determine the pullorum status of a breeding flock. 

 Failure to recognize this fact may lead one into considerable difficulty. 



Appearance of Infection in Flocks Previously Negative 



The matter of maintaining a flock free from pullorum disease is of great con- 

 cern to the flock owner and the testing agency. Progress in eradication can not 

 be expected if infection reappears as fast as it is eliminated from flocks. As long 

 as free stock is exposed to pullorum infection, so-called "breaks" may be expected 

 to occur. 



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

 or more years, but showed infection in 1943-44. Seventeen "breaks" are listed, 

 which is four more than occurred the previous year. In four cases the amount 

 of infection exceeded 1 percent. Two flocks had been negative for one year, 

 three for two years, three for four years, two for five years, one each for seven 

 and eight years, two for nine years, and one each for ten, eleven, and fourteen 

 years; 



In nine cases the explanation for the "breaks" was unknown, in two the in- 

 fection was introduced from an infected supply flock, in three through the pur- 

 chase of questionable stock, in one possibly through inadequate preventive 

 measures, in one through contest birds, and in one no information was obtained. 



In ten flocks a negative test was obtained through intensive retesting. In six 

 flocks no retesting was carried out by the flock owner. 



The appearance of pullorum infection in a flock previously negative may be a 

 very serious problem, especially in the larger breeding flocks and if the infection 

 is detected late in the season. The majority of flock owners have no conception 

 of the difificulties that may follow a "break" in a puUorum-free testing record. 

 When infection is detected, at least four weeks are required before the next test 

 can be applied. If the eggs from the flock are used for local hatching or sold to 



