| Abstract: | Thirty pigs, weighing 17 to 24 kg, were exposed to lead or sodium acetate orally or intraperitoneally (IP) 6 days each week for 13 weeks. These pigs were extremely tolerant of lead. Only mild clinical signs of lead toxicosis were observed in orally lead-exposed pigs despite blood lead concentrations of up to 290 micrograms/dl. Four IP lead-exposed pigs died, but eight other IP lead-exposed pigs survived the exposure period despite blood lead concentrations up to 14,300 micrograms/dl. Lead exposure caused marked decreases in blood delta-aminolevulinic acid dehydratase activities of all pigs and moderate decreases of blood hemoglobin concentrations, hematocrit percentages, mean corpuscular volumes, mean corpuscular hemoglobin concentrations, and mean corpuscular hemoglobins in IP lead-exposed, but not in orally lead-exposed pigs. Basophilic stippling was observed in erythrocytes of lead-exposed pigs, but not in those of control pigs. |
