Leukocyte concentration
A 20μl blood filled capillary was released in 1ml of a kit solution
(LEUKO-TIC “blue”, Bioanalytic, Germany). This solution allows a
microscopic count of leukocytes after the lysis of the erythrocytes and
the fixation of the leukocyte nucleus colored in light blue. The
leukocyte counts were done at x100 enlargement using a Malassez counting
chamber by a single observer (C.R.). Only the leukocytes entirely
located inside the four 1mm² corner squares (total volume of
4*1mm2*0.2mm = 0.8µl) were counted. All the leukocyte
counts were done within 24 hours after blood collection.
Between 2013 and 2015, the leukocyte concentration was determined for 79
samples from 34 dominant individuals sampled between two and three
times. 23 individuals had two samples in different years and 11
individuals had three.
Leukocyte counts
Immediately upon blood collection, a drop of blood was smeared onto a
slide, later stained with Giemsa stains using an aerospray (Aerospray
Hematology Slide/Cytocentrifuge 7150, Wescor, France). Neutrophils,
lymphocytes, monocytes, eosinophils and basophils were counted
(observer: CR) up to 100 leukocytes, at 100x enlargement, according to
Hawkey and Dennett’s criteria
(Hawkey
& Dennett, 1989). The basophil count was low for nearly all individuals
(min = 0, max = 49, median = 0) and therefore excluded in the subsequent
analyses.
Between 2011 and 2015, the leukocyte counts were determined for 169
blood smears from 52 dominant individuals sampled between two and five
times. 18 individuals had two samples in different years, 12 had three,
13 had four, and 9 individuals had five. 33 of them were both measured
for leukocyte concentration and leukocyte counts (which corresponds to
75 measurements).