Evaluation of the sub-human primate tube test for pregnancy in primates.

SUMMARY A haemagglutination inhibition test, developed specifically for primates, diagnoses early pregnancy in the chimpanzee, gorilla, orangoutan and baboon. The test was sensitive and reacted positively when the concentration of gonadotrophin in urine was equivalent to 0,03 i.u. human chorionic gonadotrophin per ml. This degree of sensitivity and the certitude that it cross-reacts with primate luteinizing hormone probably accounts for most of the false positive results. 87 Biological pregnancy tests for women have been superseded by immunological tests which have been used, with varying success, to diagnose pregnancy in apes and monkeys. Recently a 'specific' haemagglutination inhibition test has been developed which reacts positively with chorionic gonadotrophin (CG) of humans (RCG), the great apes, baboons and macaques, but not with follicle stimulating hormone (FSH) or luteinizing hormone (LH) of baboons or macaques (Hodgen & Ross, 1974). Preliminary results by these workers with this test, using urine or urine extracts from pregnant and non-pregnant rhesus monkeys (Macaca mulatta), are encouraging. The reagents are now available as a kit (Ortho Diagnostics Inc., U.S. Route 202, Raritan, New Jersey 08869, U.S.A.) in which form it is known as the 'sub-human primate tube' (SHPT) test. The present study was done to evaluate the SHPT test and to compare the results with those obtained from ape and baboon urine using a commercial haemagglutination inhibition (HI) test used for diagnosing pregnancy in women and ('Pregnosticon'; Organon Laboratories Ltd, Crown House, Morden, SM4 5DZ) which has an accuracy of 99% (Hobson 1968).