Effects of time storage and analytical temperature on Fossomatic cell counts in cows milk

This study evaluated the effects of time of storage and analytical temperature on the somatic cell count (SCC) in cow milk. To this end, counts were performed on 1200 cow milk samples using a flow cytometry cell counter (Fossomatic 400). The conditions tested were analytical temperature, use of a preservative [without preservative (WP) and with bronopol (BR)], and age of the milk. Tests were performed at two temperatures (40 and 60 degrees C) on preservative-free samples, 1 hour after collection and on samples preserved with potassium dichromate (PD), at 1 hour and at 1 to 4 days post-collection. Test temperature did not modify the SCC of the milk samples analyzed. Heating samples 1 h post-collection at 60 degrees C failed to improve the SCC results. Similar counts were obtained for PD-preserved samples stored for 1 to 4 d at 4 degrees C, suggesting the possibility of performing Fossomatic SCC on cow milk samples stored for this length of time.