Urinary progesterone in free-ranging red howler monkeys (Alouatta seniculus): preliminary observations of the estrous cycle and gestation.

The goals of this study were to develop and validate a radioimmunoassay (RIA) for measurement of unconjugated progesterone (P) concentrations in the urine of red howler monkeys (Alouatta seniculus) and to use urinary P profiles to characterize the reproductive cycle of this species. Analysis of P profiles from two females provided a preliminary estimate of the length of the estrous cycle (mean days +/- S.E.M. = 29.5 +/- 1.5; n = 2), and indicated that one female red howler copulated throughout two apparent estrous cycles. Urinary P concentrations during two confirmed pregnancies (211.8 +/- 29.7 ng P/ml) were higher (P < 0.05) than during the luteal phase (77.4 +/- 10.6 ng P/ml; n = 4) of the cycle.

Field application of Telazol (tiletamine hydrochloride and zolazepam hydrochloride) to immobilize wild red howler monkeys (Alouatta seniculus) in Venezuela.

Telazol (TEL) (tiletamine hydrochloride and zolazepam hydrochloride combination) was used to immobilize 50 wild red howler monkeys (Alouatta seniculus) in Venezuela between October 1989 and February 1991. The mean (+/- SD) dosages of TEL used for adult males and adult females were 22.4 (+/- 7.3) mg/kg and 22.5 (+/- 5.0) mg/kg, respectively. Juveniles of both sexes received a mean dose of 30.5 (+/- 5.6) mg/kg. The induction time for TEL ranged from 1 to 6.2 min. Thirteen animals were given an additional dosage of ketamine hydrochloride manually when they recovered from the first injection of TEL. Total recovery times ranged from 39 to 308 min. There were no apparent side effects to the fetuses of two pregnant females.