DISTRIBUTION OF TESTS AND REACTORS 



A total of 1,017,113 chicken samples from 11 counties was tested and the 

 percentage of positive tests was 0.0009 (table 1). Only Worcester County revealed 

 reactors which were confined to one Rhode Island Red breeding flock that was 

 negative the previous season. Plymouth, Essex, Middlesex, and Worcester Coun- 

 ties led in the number of samples tested. 



The following breeds were tested: Australorp, Bantam, Barred Plymouth 

 Rock, Columbian, Cornish, Crosses, Delaware, New Hampshire, Rhode Island Red, 

 White American, White Leghorn, White Plymouth Rock, White Wyandotte. 



The White Plymouth Rock, Barred Plymouth Rock, Rhode Island Red, New 

 Hampshire, and White Leghorn were the predominating breeds tested. Of the 

 total samples tested, 35.05 percent were taken from White Plymouth Rock, 16.42 

 percent from Barred Plymouth Rock, 16.25 percent from Rhode Island Red, 13.89 

 percent from the New Hampshire, and the remainder from other breeds. 



Of the 925,518 samples collected from females 41,717 were from hens and 

 883,801 from pullets, with 0.011 and 0.0005 percent reactors respectively. Among 

 the 91,595 samples collected from males none were positive. 



ANNUAL TESTING OF FLOCKS 



Table 2 lists the results from flocks tested (1) for the first time, (2) intermit- 

 tently, (3) for two consecutive years, and (4) for three or more consecutive years. 



In the group tested for the first time 46 flocks were tested which revealed no 

 reactors. It is of interest to note that while the number of flocks more than doubled 

 over that (22) of the previous season, the number of tested birds decreased from 

 52,912 to 37,166. The average number of birds to a flock in this group was 808. 

 The increase in the number of the small fancy breed flocks tested explains the marked 

 reduction in average flock size. 



In the intermittent and two-year groups, no reactors were detected. The 

 average number of birds per flock for the intermittent and two-year groups were 

 4,384 and 2,958, respectively. 



In the group tested for three or more consecutive years, there were 184 flocks, 

 representing 843,196 tests, of which 0.001 percent were positive. In comparing 

 these results with those of the previous season, significant decreases are observed 



Table 2. Annual Testing Versus Single and Intermittent Testing 



