The toxicity of fumonisin B-1, B-2, and B-3, individually and in combination, in chicken embryos

Three recently described and toxicologically important mycotoxins, fumonisi n B-1 (FB1), fumonisin B-2 (FB2), and fumonisin B-3 (FB3), produced by Fusa rium moniliforme in various grains, have been associated with a number of d iseases in both humans and animals. The toxicity of purified FB1, FB2, and FB3, individually and in combination (3:1:1 ratio), were evaluated with reg ard to their embryo toxicity by injection of the toxins into the air cell o f chicken eggs at 72 h of incubation. Under these conditions, FB1 at doses of 0, 2, 4, 8, 16, 32, and 64 mug per egg resulted in embryonic mortality o f 5, 12.5, 17.5, 20.0, 52.5, 77.5, and 100%, respectively. The 50% lethal d ose for FB1, when injected into the air cell of embryonating chicken eggs, was determined to be 18.73 mug per egg. A comparison of the toxicity of FB1 , FB2, and FB3, individually and in combination (3:1:1 ratio), at doses of 16 mug of total fumonisin per egg, indicated that the toxicity of the fumon isins differed, FB1 being the most toxic. Microscopic examination of chicke n embryos exposed to fumonisin did not reveal any gross developmental abnor malities; however, severe hemorrhages of the head, neck, and thoracic area of the dead embryos were evident.