ANNUAL REPORT, 1941 99 



Sexing by Down and Shank Color. (W. C. Sanctuary.) The sexing b\- down 

 and shank color of 948 College pedigreed Barred Rock chicks was done with 

 a 95.36 percent accuracy compared to a 95.15 percent accuracy by the vent process 

 method with the same chicks. The chicks were first judged by the down and 

 shank characteristics. 



Restricted Feeding on Range. (J. H. Vondell.) At 10 weeks of age, one half 

 of the College Barred Rock chicks was placed on a restricted plan of feeding, 

 while the remainder continued on the free-choice feeding of mash, oats, and corn. 



The restricted plan consisted of feeding mash and oats until 10 a. m., when the 

 hoppers were closed and no feed given until the 4. p. m. allotment of whole corn. 

 The pullets were housed September 12 and both lots were placed on full feeding. 

 The restricted plan resulted in a saving of 1.52 pounds of feed per chicken 

 during the 15-week period. At 6 months of age the restricted and full-feeding 

 lots weighed exactly the same, 5.85 pounds. There was no difference in maturity 

 as determined by age at first egg. The laying-house mortality to April 1 was 

 practically the same for the two lots. Also, egg production was quite close: 

 57.86 percent for the full-feeding and 62.88 percent for the restricted lot. 



These studies are being continued. 



DEPARTMENT OF VETERINARY SCIENCE 



J. B. Lentz in Charge 



Poultry Disease Control Service. (H. Van Rockel, K. L. Bullis, O. S. Flint, 

 and M. K. Clarke.) 



1. Pidloru?n- Disease Eradication. During the 1940-41 season the laboratory 

 tested 309 chicken flocks representing 527,328 birds and 538,589 tests. The 

 percentage of reactors (0.09) was the lowest in the twenty-one-^-ear testing period. 

 Of the total 478 reactors, the bulk was identified in one flock. 



Testing service was rendered to flock owners in 11 counties. Middlesex and 

 Worcester counties led in the number of birds tested. No reactors were found in 

 Barnstable, Essex, Hampshire, Plymouth, and Worcester counties. 



Five flocks which were non-reacting the previous year revealed infection dur- 

 ing the 1940-41 season. In two instances a plausible explanation for the infection 

 was obtained. In all instances but one the percentage of reactors was verj^ low, 

 less than one-half of 1 percent. 



Flocks tested for the first time revealed the highest percentage of infection. 

 Among the flocks (41) tested for two consecutive years, no reactors were found. 

 Among the 210 flocks tested for three or more consecutive years, representing 

 437,145 birds and 446,694 tests, 0.08 percent reactors was revealed. 



Approximately 88 percent of the total birds tested was confined to 100 percent 

 tested, non-reacting flocks (256). Forty-three flocks were partially tested and 

 non-reacting, representing 28,874 birds. Ten flocks were classified as positive, 

 representing 34,853 birds. 



Of the total birds tested, 490,759 were females and 47,830 were males. The 

 percentages of reactors were 0.08 and 0.17, respectively. 



A total of 4,417 samples collected from fowl other than chickens was tested for 

 pullorum disease. The species tested included turkeys (4,259 tests), pheasants 

 (115), guinea fowl (22), geese (13), ducks (5), and quail (3). Reactors were de- 

 tected in three of the 32 turkey flocks, but in only one instance was 5. pullorum 

 isolated. No reactors were detected among the other fowl tested. 



The testing results indicate that Massachusetts is making progress in elim- 

 inating pullorum disease from its chicken and turkey breeding flocks. 



