cies, the size of erythrocytes and the number per 

 cubic millimeter. 



Perhaps some of the variability in heterophil 

 count on pigeons experienced by different in- 

 vestigators was due to diurnal rhythm, the ex- 

 istence of which was worked out by Shaw ( 1933) . 

 He found that heterophil counts on the average 

 were 76 percent higher in the afternoon than in 

 the morning. The afternoon rise for 7 birds 

 was: 1, no change; 2, rise of 106 percent; 3, rise 

 of 38 percent; 4, rise of 55 percent; 5, rise of 

 143 percent; 6, rise of 54 percent; and 7, rise 

 of 138 percent. 



ARNETH COUNTS 



Arneth counts were given for a group of 

 chickens discussed in chapter 2, page 85; and in 



heterophils and eosinophils no more than 5 lobes 

 were found. Likewise, no more than 5 were 

 found for turkeys (table 22), pheasants (table 

 23) and geese (table 24) . The index values for 

 male turkeys ranged from 1.75 to 2.16, with an 

 average of 1.95; for females, it was from 1.65 to 

 2.45, with an average of 2.09. For pheasants it 

 was from 1.84 to 2.58, with an average of 2.27. 

 Only two slides were obtained from the geese; 

 they read 2.06 and 2.38. Counts were not made 

 on eosinophils for any species except the Canada 

 goose — after considerable searching 16 cells were 

 found on each slide. The indices were 3.75 and 

 4.25; thus there is a preponderance of cells with 

 3, 4, and 5 lobes — a situation that thus far has 

 not been observed either in eosinophils or in 

 heterophils for this or any other species studied. 

 Sugiyama (1938) gave Arneth counts for 8 

 species of birds. His data for the domestic 



Table 22. — Domestic turkey (White Holland): 

 Arneth counts on heterophils 



Table 23. — Rin^-necked pheasant (adult 

 males) : Arneth counts on heterophils 



Table 24. — Canada goose (adult males) : Arneth 

 counts on eosinophils and heterophils 



220 



