Introducing a combined Leishman-Giemsa stain as a new staining technique for avian blood smears

Background: The use of conventional stains including Giemsa, Wright and Leishman have become an essential tool for differential diagnosis of cells in peripheral blood. Aims: The aim of the study was to develop a new combination of Leishman-Giemsa (L&G;) stain for avian blood smears and to compare its efficacy with conventional staining methods. Methods: Three sets of peripheral blood smears, one smear for L&G; stain and two other smears for Leishman and Giemsa stains, created from 50 broiler chickens blood samples. All the three sets of slides were blind screened by two expert clinical pathologists and scored based on the staining characteristics (4 parameters) such as nuclear features of red blood cell (RBC) and white blood cell (WBC), cytoplasmic features and cytoplasmic granularity of WBC. The average grading score assigned by two experts for each staining method were compared. Results: The average grading score of two conventional Leishman and Giemsa staining methods were significantly lower (P<0.001) than new L&G; staining method in avian nuclear features of the RBC and WBC. The L&G; stain gave a better clarity of nuclear features of avian RBC and WBC. The new L&G; staining technique created significant differences (P<0.001) in cytoplasmic features of avian WBC compared to the other two methods. Conclusions: For the first time, the results of the present study showed that the avian blood cells are more desirable stained with a new combination of L&G; stain. In addition, it gives a better nuclear and cytoplasmic differential staining than the conventional Giemsa and Leishman stains when used alone.