Abstract
This study investigates the in vitro phagocytic activity of blood neutrophils of dogs in Sri Lanka for Escherichia coli. The study sample comprised of 70% mongrel and 30% cross bred dogs of both sexes. The leukocyte isolation method described yielded up to 12,930/ìl viable leukocytes of which 61-90% was neutrophils, with viability ranging from 90-99% (mean 96%). The mean percent phagocytosis (MPP) of canine blood neutrophils was significantly higher at 30 minutes incubation (89%) than at 15 minutes incubation (70 %) with E.coli. The findings support the fact that innate immunity can be measured qualitatively and quantitatively by the technique described which will be useful for the identification of immunocompromised dogs.