Total and free iodothyronine changes in response to transport of Equidae (Equus asinus and Equus caballus)

In this study the effects of short distance road transport on total and free iodothyronine changes in 12 stallions (Equus asinus and Equus caballus) were evaluated. Donkeys (n = 6) and horses (n = 6) were transported for a distance of 50 km. Blood samples were collected 1 week before transport in basal conditions, 1 week later immediately before loading, and after transport and unloading. After transport, donkeys showed significant increases in circulating T4 (P ≤ 0.01), fT3 (P ≤ 0.001), and fT4 (P ≤ 0.01) levels; while horses had significant increases in circulating T3, fT3 and fT4 (P ≤ 0.01) levels. Compared to donkeys' values, horses showed lower T4 values in basal condition, before and after transport (P ≤ 0.001); higher fT3 values in basal condition and before (P ≤ 0.001), and lower values (P ≤ 0.001) after transport; higher fT4 values (P ≤ 0.001) in basal condition. The results indicate that short road transport of donkeys and horses induces the activation of the thyroid gland, with the same release of fT3 and fT4 iodothyronines, but with different preferential release of T3 in horses and T4 in donkeys after transport. Veterinaria