Biochemical and hematological evaluations of black howler monkeys (Alouatta pigra) in highly degraded landscapes in Mexico.

Background: Loss and fragmentation of Neotropical primates' habitat can alter the health and individual adaptation. Physiological parameters reflect health status and individuals responses to the habitat conditions.

Methods: We captured six wild adult females and six adult males of Alouatta pigra to evaluate their physical condition (body mass, respiratory and heart rate, and rectal temperature), hematology and blood chemistry on fragmentation habitat condition at southeastern Mexico.

Results: The males weighed more than females, but the female' temperature, respiratory rate, and heart rate were higher. Low values of hemoglobin, hematocrit, and red blood cells suggest some degree of anemia in these howler monkeys. Low levels of the total protein, albumin, albumin/globulin Ratio, and low levels of blood urea nitrogen suggest that howler monkeys could have protein and carbohydrate deficiencies.

Conclusions: Howler monkeys living under the highly degraded conditions at Balancán, Tabasco, could be showing adaptability by modifying their physiology, hematology, and blood chemistry in response to the conditions of their fragmented landscape.