Plasma concentration of iditol dehydrogenase (sorbitol dehydrogenase) in ponies treated with aflatoxin B1.

The study investigates the impact of varying dosages of Aflatoxin B1 on the plasma concentration of iditol dehydrogenase (ID), a marker of liver damage, in Shetland ponies. The study found a correlation between higher doses of Aflatoxin B1 and higher plasma concentrations of ID, suggesting liver damage.

Research Design

Four groups of clinically normal Shetland ponies were set up for the experiment, assigned different doses of Aflatoxin B1. The toxin was given at 2mg/kg body weight to group A, 1mg/kg to group B, 0.5mg/kg to group C. The control group D received a placebo. One pony from group A died 68 hours after dosing, and another died 76 hours after dosing. After administering the toxin/placebo, plasma samples were taken at 4-hour intervals to measure ID concentrations.

Findings

• Mean peak ID values (an indicator of hepatic damage) varied significantly across the groups, with the highest in group A (1514.0 IU/l) followed by group B (192.6 IU/l), group C (8.5 IU/l), and group D (controls) had the lowest (2.7 IU/l).
• The mean ID value of group A became significantly higher than that of the control group 5 to 6 hours after dosing.
• The mean ID values for groups B and C also significantly exceeded those of the control group after 12 to 16 hours and 20 to 24 hours respectively.

Conclusion

The results of the study suggest that higher doses of Aflatoxin B1 contribute to higher ID plasma concentrations, implying liver damage. The deaths of two ponies from the highest dosage group add credence to this interpretation. The significant elevations in ID values relative to the control group at different time periods after dosing for groups A, B, and C indicate a dose-dependent relationship between Aflatoxin B1 and liver damage in Shetland ponies.