Hematology of chicks experiencing marginal vitamin B6 deficiency

An economical vitamin B6-deficient ration, which was palatable to broiler chickens, was prepared and fed to 1-day-old broiler chicks. The experimental ration was a glucose-soybean meal diet. Vitamin B6 was removed by washing the soybean meal with water. Microbiological analysis revealed that the washed ration contained .45 mg vitamin B6 activity/kg. Experimental rations were formulated to contain .5, 1.0, and 3.0 mg added pyridoxine HCl/kg of ration. These supplemental levels produced total pyridoxine concentrations, as assayed, of .95, 1.48, and 3.18 mg pyridoxine HCl activity/kg of diet. Chicks were grown to 7 weeks of age and characteristic B6 deficiency traits, including increased mortality, decreased body weight gain, and increased incidence of abnormal leg conformation, were quantitated or observed. An extensive hematological evaluation at 4 weeks of age indicated that this marginal B6 deficiency resulted in increased erythrocyte numbers, decreased mean corpuscular hemoglobin levels, and increased erythrocyte fragility. No changes in hematocrits, total hemoglobin level, intracellular hemoglobin concentration, or reticulocyte number were found. These results indicate that anemia did not occur in broilers experiencing a moderate vitamin B6 deficiency. The hematological condition is described as microcytic, normochromic polycythemia.