The Determination of the Number of Body Cells in Milk by a Direct Method.

Abstract

At the present time, the method in most general use in Board of Health and similar laboratories for determining the number of these body cells present in a given sample of milk is the so-called "smeared sediment" method first devised by Stokes and Wegefarth2 of Baltimore. Later this method was modified by Stewart3 of Philadelphia and Slack4 of Boston. These modifications have improved the accuracy of the method but the results obtained with it have not been entirely satisfactory. In 1905, a "volumetric" method for determining the number of body cells was suggested by Doane and Buckley.5 This method uses the well-known Thoma-Zeiss hemacytometer for examining the sediment secured by the use of the centrifuge. Practically the same method was devised independently by Savage.6 The results obtained by this method show larger numbers of body cells present than do those obtained by the " smeared sediment" method. Nearly all of the research work along this line is being done by the "volumetric" method because there seems to be general agreement that it is more accurate than the " smeared sediment" method. Russell and Hoffman7 find that they get better