Table 16. — Diameter of granulocytes 



Breed 



Single Comb White Leghorns . 



Average for group 



Single Comb White Leghorns. 



Average for group. 

 New Hanipshires. . . . 



Average for group 



Columbian Plvmouth Rocks. 



Average for group. 



Source ' 



RPL6. 



RPL 15. 



Commercial. 



Commercial 



Bird = 



Heterophil 



Range 



6. 2- 7. 8 

 6. 0-10. 

 8. 8-10. 1 



8. 6-10. 6 

 5. 1- 9. 2 

 6.6- 7.9 



9.8-11.4 

 8. 2-10. 5 

 8. 4-10. 5 



6. 5-10. 3 



7. 4- 8. 4 

 9. 1-10. 6 



Aver- 

 age 



6.8 

 7.6 

 9.4 

 7.9 

 9.4 

 7.6 

 7.2 

 8.1 

 10.6 

 9.4 

 9.7 

 9.9 

 8.9 

 7.9 

 9.6. 



Eosinophil 



Range 

 M 



5. 3- 6. 8 



5. 5- 8. 8 



6. 7-10. 9 



6. 4-10. 1 

 5. 7- 7. 6 

 4. 8- 6. 



6. 3- 8. 5 

 6. 1- 8. 3 



7. 5- 9. 4 



6.3-^ 

 6.2- 

 8.5- 



7.3 

 10. 1 



Aver- 

 age 



6.1 

 6.7 

 8.3 

 7.0 

 8.0 

 6.6 

 5.4 

 6.7 

 7.8 

 7.1 

 8.4 

 7.8 

 7.8 

 6.7 

 9.3 

 7.9 



Basophil 



Range 



Aver- 

 age 



7.4 

 7.3 

 8.8 

 7.8 

 9.3 

 7.1 

 6.9 

 7.8 

 7.3 

 9.3 

 7.8 

 8.1 

 8.1 

 9.2 

 9.9 

 9.1 



' RPL= stock from the U. S. Regional Poultry Research Laboratory. 



2 Measurements based on 10 cells per bird. 



Burnett (1908), Goodall (1909), Burckhardt 

 (1912), Forkner (1929), Hayden (1929), 

 Blakemoie ( 1934) , Cook and Dearstyne ( 1934) , 

 Magath and Higgins (1934), Biely and Palmer 

 (1935), Kelly and Dearstyne (1935), Palmer 

 and Biely (1935a and b), Cook (1937), Olson 

 (1937), Twisselmann (1939), Blount (1939a), 

 Hamre and McHenry (1942b), and Rhian, Wil- 

 son, and Moxon (1944). Twisselman clearly 

 demonstrated that there has not always been 

 agreement in regard to cell identification or cell 

 terminology. Breu.sch (1928) mentions the 

 high variability of cell counts for chickens and 

 considers it to be normal. Palmer and Biely 

 (1935a), in an exhaustive study, concluded 

 that ". . . the erythrocyte and leucocyte counts 

 of a bird fluctuate around a certain level charac- 

 teristic of the individual." Similar obsei-vations 

 were made on cattle by Ferguson, Irwin and 

 Beach (1945). Excellent reviews on variabil- 

 ity in blood counts have been given by Carrey and 

 Bryan (1935) and by Sturgis and Bethell 

 (1943). Although these reviews deal primarily 

 with a discussion of cell counts of blood samples 

 taken from mammals, the problems and prin- 

 ciples involved are equally applicable to the 

 avian species. 



Diesem (1956) and Lucas and Denington 

 (unpublished data) have sought to establish the 

 95-percent fiducial interval for the normal blood 



values of chickens. The latter authors also 

 noted that the variability of blood-cell counts in 

 birds was no greater than that reported in 

 mammals. 



A superficial comparison of tables 18, 19, 20, 

 and 21 (for ducks, geese, pheasants, and 

 pigeons) with table 17 (for chickens) might give 

 the impression that the first four species were 

 highly variable in comparison with the last. 

 However, this is not the case, and individual 

 records for chickens are just about as variable 

 as for wild birds. The values in table 17, which 

 seem relatively uniform, are based on large 

 groups of chickens — 33 to more than 100 in each 

 group. The data from the Laboratory stock 

 were part of a project carried out imder a grant 

 from the United States Atomic Energy Commis- 

 sion. Two inbred lines were used, 6 and 15, and 

 data from the two lines have been combined in 

 table 17. Line 6 was developed toward resist- 

 ance to avain lymphomatosis and line 15 to- 

 ward susceptibility to this pathologic condition 

 (Waters, 1945). There was a statistically sig- 

 nificant difference between the means for each 

 line on almost every type of blood determination; 

 thus the values for erythrocyte count, hemoglo- 

 bin, hematocrit, and buffy coat were higher for 

 line 6 than for line 15. The only values not sig- 

 nificantly different were the eosinophil averages. 



In view of the high variability in counts on in- 

 dividual birds, two questions are raised: 



215 



