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Lead analyses were performed on capillary blood samples from 2-week-old Japanese quail, using a standard microprocedure. The difficulties encountered included coagulation when the blood aliquot was diluted with Triton X-100, loss of lead during the ashing stage, and non-parallel calibration curves. Recommendations to overcome these problems are presented.

Red blood cell delta-aminolevulinic acid dehydratase (RBC-ALAD) activity has proven to be a sensitive indicator of lead exposure in humans. The depressed enzyme activity and its negative correlation to blood lead concentrations are well-known effects of lead exposure in man. The sensitivity of RBC-ALAD activity in young Japanese quail exposed to low levels of lead as lead acetate was investigated. Two groups of nine birds each were fed purified diets containing either no added lead or 25 micrograms of lead per g. of diet. After 2 weeks, blood samples for hematocrit, hemoglobin, and enzyme determinations and renal, hepatic, duodenal, and tibial tissues were collected. There were no significant differences between controls and lead-fed birds in body, kidney, duodenal, and tibial weights, or in hematocrit and hemoglobin concentrations. However, the renal, hepatic, duodenal, and tibial lead concentrations were significantly (P less than 0.001) greater in the lead-treated birds. The activity of RBC-ALAD in the group fed lead was 45% of that in the control group; these values were significantly different (P less than 0.001). RBC-ALAD activity expressed as the log. base 10 showed significant (P less than 0.02) negative correlation with both hepatic and tibial lead. The study demonstrates that the activity of RBC-ALAD in the Japanese quail is a very sensitive indicator of lead exposure.

Studies of magnesium deficiency, requirement and toxicity in the young Japanese quail (Coturnix coturnix japonica) were conducted. Day-old birds were fed an adequate purified diet containing 35% soy protein to 2 weeks of age. Residual magnesium in the diet without any added magnesium salts was 21 p.p.m. magnesium was supplied by graded amounts of MgSO4 to a total of 11 levels ranging from 125 to 2,000 p.p.m. Deficiency signs included poor growth, and occasionally excitability, gasping and convulsions. Most mortality occurred during the first 7 days. The maximum dietary magnesium concentrations that produced the minimal significant deviation from normal values for mortality, body weight, hemoglobin and tibia ash was 225, 200, 250 and 250 p.p.m., respectively. Based on these measurements, 300 p.p.m. magnesium is considered adequate to meet the young quail's requirement under the conditions of these experiments. With 2,000 p.p.m. magnesium, the only adverse effect was an increase in mortality. Between 200 and 1,000 p.p.m. magnesium there was a linear relationship between concentration of magnesium in the tibia and the log of the concentration of dietary magnesium. This suggests that tibia magnesium concentration might be useful for bioassay of magnesium in foodstuffs.