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Journal of Agricultural Research 
Vol. IX, No. 5 
find an average of 8,267,000 erythrocytes per cubic millimeter, 24,500 
leucocytes, and 85 per cent of hemoglobin. 
Dinwiddie, 1 in his bulletin dealing with a study of the blood of normal 
and cholera-infected pigs, reports upon 16 normal animals. These pigs 
were between the ages of 3 and 5 months. He found the average number 
of red corpuscles to be 6,334,000 and the leucocytes 11,800. 
Differential counts of the leucocytes are reported by Drake, 2 Giltner, 3 
and Dinwiddie. 4 
Drake, in his studies on trichinosis, made differential counts on 15 
normal pigs. He recognizes only three classes of leucocytes. His 
results are as follows: 
Lymphocytes.33 to 77 per cent; average, 56.4 per cent. 
Polynuclears. 18 to 66 per cent; average, 38.4 per cent. 
Eosinophiles... 1 to 12 per cent; average, 5.13 per cent. 
Giltner recognizes five classes of leucocytes and gives the following 
percentages based upon 24 examinations: 
Lymphocytes. 30.0 to 79.8 per cent; average, 51.6 per cent. 
Large mononuclears.8 to 10.0 per cent; average, 4.6 per cent. 
Polymorphs. 13.0 to 60.0 per cent; average, 37.0 per cent. 
Eosinophiles. 1.2 to n.o per cent; average, 5.2 per cent. 
Mast cells.2 to 5.6 per cent; average, 1.3 per cent. 
Dinwiddie gives the following percentages based upon 16 examinations: 
Mononuclears._. 24 to 81 per cent; average, 59.0 per cent. 
Polymorphs. 16 to 75 per cent; average, 35.0 per cent. 
Transitional. 1 to 6 per cent; average, 2.9 per cent. 
Eosinophiles. 1 to 10 per cent; average, 4.0 per cent. 
Basophiles. 1 to 2 per cent; average, 1.1 per cent. 
methods of study 
The 25 young pigs used in this work were obtained from three litters 
of pigs bom from healthy sows and were farrowed on the university 
farm. They were healthy, strong pigs of mixed breeding. The pigs 
ranged in age from 2 to 42 days, and in weight from 2.5 to 18 pounds. 
The age, weight, sex, and condition are included in Table II. 
The larger pigs were selected from animals which had been purchased 
upon the open market at the South St. Paul stock yards, and were to be 
used for serum production. The pigs came from various points through¬ 
out the Northwest, and when a load was received a number of the pigs 
were selected for this work. The pigs selected were of good quality. 
They were first weighed and tagged, then given a few days' rest in a 
small inside pen. During this time they received feed and water three 
1 Dinwiddie, R. R. Studies on the hematology of normal and cholera-infected hogs. Ark. Agr. Exp. 
Sta. Bui. 120, p. 21-41, 8 fig. 1914. 
2 Drake, A. K. Trichinosis. In Jour. Med. Research, v. 8 (n. s. v. 3), no. 1, p. 255-267, 1 pi. 1902. 
8 Giltner, Ward. Op. cit. 
4 Dinwiddie, R. R. Op. cit. 
