Tuberculin test in experimentally sensitized goats (Capra hircus)

Abstract

The tuberculin skin test was established with the aim to be applied in the diagnosis of tuberculosis in experimentally sensitized goats. Thirty goats were alocated into three groups with ten animals each. The animals in group A were sensitized with Mycobacterium avium sample D4; group B with Mycobacterium bovis sample AN5; and group C (control) was inoculated with saline solution. The results of the simple cervical test after 72h of bovine tuberculin inoculation was interpreted as follow: positive reaction, when there was an increase in the skin fold thickness greater than 3.9mm; suspicious, when from 1.8 to 3.8mm; and negative when less than 1.7mm. The analysis of the results of the comparative cervical test between M. avium and M. bovis and analysed, 72h after tuberculin, indicated positive reactions, when the increase in skin fold thickness induced by M. bovis was greater than that one induced by the avian tuberculin at least 2.5mm; it was considered suspicious when the difference between the bovine and avian tuberculin reactions was from 1.9 to 2.4mm; and negative when this difference was smaller than 1.8mm. The histological evaluation of the local specific tuberculin response, were performed in skin samples collected from five goats in group A, five in group B, and four in group C, the results were the presence of mononuclear inflammatory infiltrate at 96h after tuberculin inoculation.