[Cock fighting as a model of emotional stress]

Aggressive and passive roosters displayed agonistic behaviour towards each other. The formers revealed a highly agonistic attitude in the first half of the experiment followed by an obvious decline. The passive roosters revealed a relatively stable agonstic attitude. The electrocardiorhythmograms showed that handling of the roosters and other manipulations masked the heart primary response to cock-fighting, and that the analysis of the heart rate during restitution only helped to estimate their emotional tension during fighting. Positive correlations between the aggressiveness and noradrenaline content in the plasma, were obtained. The latter correlated with the sexual activity as well. The agonistic behaviour entailed an insignificant activation of the adrenals.