ABSTRACT
The tuberculin sensitivity of 173 guinea-pigs was determined by testing with o,05 ml of 1/10 O.T. These animals were inculated with known doses of M. leprae or M. lepraemurium and the results were compared with reaction obtained in inoculated BCG., an in normal non-inoculated (control) guinea-pigs. The bacillary contents of the M. leprae and M. lepraemurium suspension were estimated by weighing the bacilli contained in 10-20 ml of the suspension, after chlorofrom separation. The guinea-pigs were divided in four groups: Group 1 - 59 guines-pigs inoculated with M. leprae suspensions as follows: a - 10 inoculated with suspension containing nearly 10.0 mg of bacilli by peritoneal route; b - 20 inoculated with suspension containing nearly 0.8 mg of bacilli by peritoneal route; c - 10 inoculated with suspension containing nearly 0.17 mg of bacilli by intra-cutaneous route; d - 19 inoculated with "lepromin" containing 0.074 mg of bacilli (in 0.1 ml) by intra-cutaneous route. Group 2 - 38 guinea-pigs inoculated with M. lepraemurium suspension as follows: a - 38 inoculated with suspensions containing nearly 10.0 mg of bacilli by peritoneal route; b - 18 inoculated with suspensions containing nearly 3.33 mg of bacilli by peritoneal route. Group 3 - 51 guinea-pigs inoculated with BCG. suspensions as follows: a - 20 inoculated with suspension containing 10.0 mg of bacilli by peritoneal route; b - 31 inoculated with suspension containing 40.0 mg of bacilly by peritoneal route. Group 4 - 25 normal, noninoculated, guinea-pigs (control-group). After inoculation tuberculin reaction was made periodically by intracutaneous injections of 0.05 ml of 1/10 O.T. The results show taht the inoculation of 0.8 mg and 10.0 mg of M. leprae, by peritoneal route, suscitated tuberculin hypersensitivity in guinea-pigs, which presents the following characteristics: 1 - slow development attaining is maximun 30 days after inoculation; 2 - weak tuberculin reactions in 60.0-65.0 per cent of the...