differential count

count

a numerical computation or indication.

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differential count

a count, on a stained blood smear, of the proportion of different types of leukocytes (or other cells), previously expressed in percentages but now usually reported in absolute numbers (10⁹/l) for a better indication of abnormalities that may exist.

milk cell count

see milk cell counts.

platelet count

the count of the total number of platelets per liter (10⁹/l) of blood by counting the platelets in a counting chamber, a hematology analyzer, or by estimating the number on a stained blood smear.

sperm count

see semen concentration.

total bacterial count

determination of the total number of bacteria in the sample examined microscopically, then a calculation of the number per ml. These do not distinguish between viable and non-viable organisms. See also breed's direct smear method.

viable bacterial cell count

enumerating the number of viable bacteria present in a sample based on counting the number of colonies from a given dilution.

wool count

an arbitrary number given to wool to indicate its fiber diameter, e.g. 60's, based on an eyeball assessment of the number of hanks of yarn that could be spun from one pound of wool. Now superseded by measurement of the diameter, e.g. 20 microns.

worm count

a total worm count requires a freshly slaughtered cadaver, collection of intestinal or other fluid in an aliquot sample; in the case of lungs it is necessary to digest the tissue; counting actual worms and by multiplication measuring the total worm burden.

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differential count

Diff, white blood cell differential count Hematology The relative number of leukocytes–eg segmented and band forms of granulocytes, eosinophils, lymphocytes and monocytes in the peripheral circulation, expressed in percentages of the total WBC count. See White cell count.