A retrospective study of lead poisoning in cattle.

Information pertaining to 294 cases of bovine lead poisoning that occurred during the 15-year period from 1968 to 1982 was collected from the toxicology laboratory records at the Western College of Veterinary Medicine. Lead poisoning was seen more often in younger cattle, with 51.9% of the cases reported in animals 6-months of age or less. A statistically significant seasonal incidence was seen (p less than 0.0001) with 60.9% of the cases occurring from May to August. Lead poisoning was more common in dairy breeds than beef breeds. The relative rates in the daily and beef breeds per 1,000 cattle were 0.022 and 0.0065 respectively. No specific breed susceptibility was associated with any of the major dairy or beef breeds. Statistically significant sex-related differences for lead poisoning were not seen (p = 0.11). The most suitable biological samples utilized to confirm lead poisoning were blood, kidney and liver. These samples produced the most reliable results, with rumen and fecal samples exhibiting a high degree of variability.