Abstract
1. | This research evaluated differences in hepatic in vitro metabolism of aflatoxin B1 (AFB1) on selected avian species. | ||||
2. | Microsomal and cytosolic liver fractions were obtained from chickens, ducks, quails and turkeys; eight males and eight females of each. | ||||
3. | All microsomes studied produced AFB1-8,9-exo-epoxide (AFBO), a metabolite regarded as the active product of AFB1. Turkey microsomes produced 1·8 and 3·5 times more AFBO than quails and chickens microsomes, respectively. | ||||
4. | Males from evaluated birds produced more AFBO than females, but statistically-significant differences between genders were observed only in ducks and turkeys. | ||||
5. | The cytosolic fraction from all four species produced aflatoxicol (AFL). Turkey and duck hepatic cytosol produced more AFL than from quail and chickens. | ||||
6. | It is known that turkeys are very sensitive to AFB1, quails are intermediate and chickens are particularly resistant; the differences in AFBO production shown in our study may help to explain the different in vivo responses among turkeys, quail and chickens. | ||||
7. | Moreover, AFL may be related to AFB1 toxicity; it was produced in larger amounts by hepatic cytosol from the more susceptible species. | ||||
8. | Because AFBO production by microsomes in ducks was relatively low, it is possible that other toxicity mechanisms are involved in this highly susceptible species. |
Acknowledgments
Funding for this research was provided by the International Foundation for Science, Stockholm, Sweden (IFS grant No. B/3094-1).