Histomorphometric and functional analysis of the thyroid from broiler chicks after short-term exposure to the Fusarium sporotrichioides T-2 toxin

Thyroids from broiler chicks fed Fusarium sporotrichioides T-2 toxin were morphometrically and functionally analyzed. Thirty male Hubbard broiler chicks (one day old) were randomly divided into two groups. One group received contaminated food and the other group was used as control. Five animals from each group were killed at 7, 14, and 21 days after the beginning of the experimental treatment. The thyroids were sampled for histomorphometric evaluation and plasma was collected to determine the levels of free thyroxin. The thyroids from treated animals at 7 and 14 days showed predominance of small follicles with flatter epithelium, which was confirmed by morphometry. The differences between groups were more pronounced at 21 days, when three thyroids showing features of parenchymatous goiter and two thyroids showing features of colloid goiter were observed. The treated animals showed significantly reduced levels of free thyroxin only at 14 days. In conclusion, T-2 toxin can potentially induce goiter, which is associated with histomorphometric changes in the thyroid and decrease in the levels of free thyroxin. However, the thyroid can keep euthyroidism after a short-term exposure to T-2 toxin at low doses.

Broiler chick; T-2 toxin; Fusarium sporotrichioides; thyroid gland

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