Urinary Chorionic Gonadotropin in Middle and Late Pregnancy in the Chimpanzee

Diagnosis of Pregnancy in Chimpanzees Using the Nonhuman Primate Pregnancy Test Kit

“…This pattern fits well with the findings of previous studies which quantitated chorionic gonadotropin levels in pregnant chimpanzees [1,8,9]. Even the slight increase in the rate of positive tests found here two to four weeks preceding delivery agrees with the known late gestational rise in urinary chorionic gonadotropin levels both in this primate [8,9] and man [10]. We do not recommend that this hemag glutination inhibition test be applied routinely before or after the designated interval (days 20 to 133 of pregnancy), because the low chorionic gonado tropin levels in urine may lead to false negative responses.…”

“…During this period 151 of 153 urine specimens produced positive test results, but after the 19th week of pregnancy, the incidence of negative tests increased markedly as the levels of urinary chorionic gonadotropin declined. This pattern fits well with the findings of previous studies which quantitated chorionic gonadotropin levels in pregnant chimpanzees [1,8,9]. Even the slight increase in the rate of positive tests found here two to four weeks preceding delivery agrees with the known late gestational rise in urinary chorionic gonadotropin levels both in this primate [8,9] and man [10].…”

“…Unlike one immunologic pregnancy test for the rhesus monkey [2], the test system used in the present study does not require either collection of 24-hour urine speci mens or extraction and concentration of urine samples. Although some radio immunoassay systems [1,8,9] developed for quantitation of human chorio nic gonadotropin are well suited to measurement of chimpanzee gonado tropin, such methods are seldom practical for routine breeding management situations because of elaborate and expensive equipment needs, as well as the requirement of personnel with competence in radioimmunoassay. In addition, performance of radioimmunoassays requires at least two days.…”

Urinary Chorionic Gonadotrophin Excretion During Pregnancy in the Chimpanzee

“…The levels of chorionic gonadotrophin excretion as determined by the rat prostate bioassay are similar to those reported by Nixon et al [6]. Clegg and Weaver [3] also report peak levels of 850-1,300 HCG IU equivalents/100 ml of unextracted urine, which is very similar to the peak level of 1,550 IU/100 ml from chimpanzee Karin.…”

Duration of Chorionic Gonadotropin Production by the Placenta of the Rhesus Monkey

“…Since chorionic gonadotropin is present throughout gestation in women (7-9), chimpanzees (10,11) and gorillas (12), the absence of chorionic gonadotropin from placenta, blood and urine of these macaques after the 40th day of pregnancy makes them a valuable model for pregnancy research where the absence of chorionic gonadotropin is experimentally desirable. Since chorionic gonadotropin is present throughout gestation in women (7-9), chimpanzees (10,11) and gorillas (12), the absence of chorionic gonadotropin from placenta, blood and urine of these macaques after the 40th day of pregnancy makes them a valuable model for pregnancy research where the absence of chorionic gonadotropin is experimentally desirable.…”