Biochemistry, Doppler echocardiography, and electrocardiography evaluation in captive owl monkeys (Aotus sp).

BACKGROUND: The cardiovascular system of owl monkeys has been studied due to frequent postmortem findings of heart disease in asymptomatic animals. The silent aspect and the difficulty of early diagnosis intensify the importance of studying the cardiovascular system in this species. METHODS: Echocardiogram evaluation was carried out on 60 animals, grouped into suspect or non-suspect of having heart diseases, and evaluated through electrocardiogram, hematology, and biochemical tests. RESULTS: Doppler echocardiography indicated two animals with suspicion of left ventricular hypertrophy and eight with dilated cardiomyopathy. Suspect animals had higher cardiac measurements and reduced shortening fraction. Troponin I was detectable in two animals (0.128 ng/mL and 0.584 ng/mL), and serum albumin concentration was significantly higher in non-suspect animals (P < .05). CONCLUSIONS: The importance of echocardiographic measurements of IVSd, IVSs, LVIDd, LVIDs, LVPWd, LVPWs, LA, EF, and FS in the cardiac evaluation of captive owl monkeys was evidenced.

Contexts of rubbing behavior in Alouatta guariba clamitans: a scent-marking role?

Rubbing behaviors are well known in several primate species and are usually seen as scent-marking behaviors, with several functions proposed but still widely debated. The genus Alouatta is highly sexually dimorphic and a suitable subject for the study of sexual and hierarchical divergences associated with rubbing behavior: males should mark more than females, and dominant individuals more than subordinate ones. Three wild groups of Southern brown howler monkeys, Alouatta guariba clamitans, were studied at Morro Geisler, Indaial, Brazil, from September 2004 to February 2005. One hundred and twenty-three rubbing episodes were registered; data on performers and associated contexts showed that anogenital, dorsum and hyoid regions were the most often rubbed. Adult males rubbed significantly above expected levels, whereas subordinated females and juveniles tended to rub below the expected levels. Females were the main performers of anogenital rubbing, often preceded by defecation. The predominance of rubbing in males probably serves an important function in intrasexual communication and social interactions. Intrasexual competition can also lead to a relationship between rubbing and social status in females. Hyoid and sternum rubbing by males are probably agonistic signals associated with extragroup conflict. The possible cleaning function of anogenital rubbing does not preclude a communicative function. Whether rubbing behavior in howlers is solely for the function of scent marking or can also be a visual signal (e.g. as a display or to color the substrate with pigment) requires further study.