Normal growth and white blood cell development in large white turkey embryos

Two experiments were conducted to determine normal growth and hematological values for turkey embryos. In each experiment, differential white blood cell counts, hematocrits, sex, and body weights were recorded for 10 Nicholas Large White turkey embryos beginning at Day 12 and at select days thereafter through Day 25 of incubation. Because there were so few white blood cells present in the turkey embryonic blood, differential white blood cell counts were scored by two observers. Each observer counted for a fixed time, 5 min, rather than to a specific number of cells. A significant difference (P less than or equal to .05) due to embryo age was found for BW, hematocrit, heterophils, lymphocytes, basophils, and total white blood cell counts. Significant differences due to sex of the embryo or day by sex interaction were not found for BW, hematocrit, heterophils, eosinophils, basophils, and total white blood cell counts. A significant day by sex interaction was found for lymphocytes. No significant differences were observed between either of the main effects or their interaction for the monocyte totals. The predominant circulating white blood cell in turkey embryos was the heterophil not the lymphocyte.