White blood cell profile, Spirulina, broiler


Spirulina microalgae is an alternative protein source under consideration for feed formulation in commercial broiler production. The purpose of this study was to determine the effects of a low crude protein (LCP) diet and a LCP diet formulated with 100 g/kg Spirulina (LCP-SP) on blood cell measurements in broilers. One-day-old Ross 708 male broilers were assigned to three dietary treatments: a standard crude protein (SCP), the LCP, or the LCP-SP diet, with five pens/treatment. When the chickens were 37-days old, blood samples were obtained from 2 birds/pen. Each blood sample was used to determine 1) the concentrations of white blood cells (WBC), thrombocytes, red blood cells (RBC), hemoglobin, and hematocrit by automated hematology; 2) the proportions among WBC populations by microscopic evaluation of >300 WBC on Wright-stained blood smears; and 3) the proportions among lymphocyte-subsets by immunofluorescent staining and flow-cytometric cell population analysis. Except for monocytes, none of the blood cell measurements were affected (P > 0.05) by diet. The LCP diet resulted in increased (P ≤ 0.05) monocyte concentration and proportion compared to the SCP diet, indicating heightened inflammatory activity with lower dietary protein content. The LCP-SP diet reversed the effect of the LCP diet, resulting in monocyte concentrations and proportions not different (P > 0.05) from those of the SCP diet. The ability of Spirulina microalgae to maintain normal WBC profiles in broilers fed the LCP diet is a promising sign for its use as a proteinaceous feed component without compromising the health of the bird.