Effects of housing and short-term transportation on hormone and lymphocyte receptor concentrations in beef cattle.

The experiment was designed to evaluate the effects of housing system and short-term transportation on the pituitary and adrenal response and on blood progesterone concentrations of beef cattle. Since the use of steroid hormones in farm animals has been banned in the EU (Council Directive 96/22/EC), it seems important to study the possible modifications in serum progesterone concentrations induced by stress in cattle. Thirty-two, 6 months old male Piedmontese beef cattle (16 reared in a littered loose house, Group A, and 16 housed in a littered tying stall barn, Group B) were blood sampled at T1 (6 months old), T2 (12 months old), T3 (18 months old, before transportation to the slaughterhouse) and T4 (after transportation to the slaughterhouse) in order to measure hormonal concentrations and lymphocyte glucocorticoid (GR) and β-adrenergic (β-AR) receptor concentrations. Circulating hormone concentrations were measured using commercial radioimmunoassay kits, whereas lymphocyte receptor density was determined through binding assays. In beef cattle housed in tie stall barn a significant increase in serum cortisol concentration was observed at T3, whereas there was no effect of the housing system on blood progesterone concentrations. Short-term transportation caused a significant increase in blood cortisol and catecholamine concentrations in both groups, whereas lymphocyte GR and β-AR significantly decreased in Group A. Our data confirm the activation of the hypothalamic-pituitary-adrenal axis and the catecholaminergic system in short-term transportation and suggest that the stress-induced increase in circulating progesterone concentrations does not exceed the limit established by pending legislation.