Evaluation of adrenocortical function in Florida manatees (Trichechus manatus latirostris)

The study objectives were to determine the predominant manatee glucocorticoid; validate assays to measure this glucocorticoid and adrenocorticotropic hormone (ACTH); determine diagnostic thresholds to distinguish physiological vs. pathological concentrations; identify differences associated with sex, age class, female reproductive status, capture time, and lactate; and determine the best methods for manatee biologists and clinicians to diagnose stress. Cortisol is the predominant manatee glucocorticoid. IMMULITE 1000 assays for cortisol and ACTH were validated. Precision yielded intra‐ and inter‐assay coefficients of variation for serum cortisol: ≤23.5 and ≤16.7%; and ACTH: ≤6.9 and ≤8.5%. Accuracy resulted in a mean adjusted R²≥0.87 for serum cortisol and ≥0.96 for ACTH. Assay analytical sensitivities for cortisol (0.1 µg/dl) and ACTH (10.0 pg/ml) were verified. Methods were highly correlated with another IMMULITE 1000 for serum cortisol (r=0.97) and ACTH (r=0.98). There was no significant variation in cortisol or ACTH with sex or age class and no correlation with female progesterone concentrations. Cortisol concentrations were highest in unhealthy manatees, chronically stressed by disease or injury. ACTH was greatest in healthy free‐ranging or short‐term rehabilitating individuals, peracutely stressed by capture and handling. Cortisol concentrations ≥1.0 µg/dl were diagnostic of chronic stress; ACTH concentrations ≥87.5 pg/ml were diagnostic of peracute stress. In healthy long‐term captive manatees, cortisol (0.4±0.2 µg/dl) and ACTH (47.7±15.9 pg/ml) concentrations were lower than healthy free‐ranging, short‐term rehabilitated or unhealthy manatees. Capture time was not significantly correlated with cortisol; ACTH correlation was borderline significant. Cortisol and ACTH were positively correlated with lactate. Zoo Biol 30:17–31, 2011. © 2010 Wiley‐Liss, Inc.     

Preliminary survey of the distribution and population of chimpanzees in the Republic of Guinea

An investigation of the distribution and population of chimpanzees in the Republic of Guinea was carried out with the help of the Government authorities on the basis of a questionnaire. As a result, at least 20 out of the 36 prefectures in the country were confirmed to be inhabited by chimpanzees, and the estimated total number of animals in the present population amounted to 6,625. This number represented an approximately 50% reduction from the 13,940 estimated by the same informants on the same questionnaire based on assumptions for the past (20–60 years ago). On comparing these data with our observations in some localities, the present number of chimpanzees as estimated from the questionnaire appeared to be overestimated. Among the 16 other prefectures without any reply, at least 7 have chimpanzees according to our own and our colleagues' observations. On our modest estimate, the number of chimpanzees at present could be only about 1,420 for 30 prefectures rather than 6,625 for 20 prefectures. The true population size in the whole country may lie between the two estimates, 1,420–6,625, even including other prefectures with no information. The reduction in population size during the last 20–60 years must be half or even more. The reason for this drastic reduction of the chimpanzee population is thought to be mainly the destruction of its habitat and poaching in some prefectures adjacent to Sierra Leone and Liberia. These findings emphasize that urgent efforts need to be directed towards the conservation of the chimpanzees and their habitat, especially through international cooperative programmes.