Effect of long-distance road transport on thyroid and adrenal function and haematocrit values in Limousin cattle: Influence of body weight decrease

The purpose Of this Study was to evaluate the effect of long-distance road transport as a relevant stressor on total and free iodothyronines, cortisol levels and haematocrit values in 10 male Limousin cattle. Serum T-3, T-4, fT(3), fT(4) and cortisol concentrations were analysed by immunoenzymatic assays, Serum cortisol levels and haematocrit modifications were also evaluated on the basis of percentage body weight decrease. The results showed a general increase of total and free iodothyronines and cortisol levels after short- and long-distance road transport and a decrease 15 days after transport, as compared to basal values. Significant positive correlations between T-3 and T-4, between T-3 and fT(3), and between T-4 and fT(4) were found. These results suggest that transport stress induces an increase in the activity of thyroid and adrenal function in Limousin cattle that is evident after even a short-distance road transport and continues to increase after long-distance transport.