Dados do Trabalho

Título

Observation of short frenulum in unrelated golden lion tamarins [Leontopithecus rosalia]: a unique feature among Leontopithecus species?

Corpo do texto

Males from the Callithrichidae Family (Platyrrhini, Primates) usually have a small and relatively unspecialized penis, typical from primates which live in family groups generally consisting of an adult pair and their offspring. This is the case with many marmosets and tamarins, such as Leontopithecus sp. Anatomically, the prepuce is a double-layered fold of smooth muscle tissue, with neurons, blood vessels, mucous membrane and skin which covers and protects the glans penis and urinary meatus when penis is not erected. Within mammals, only monotremes – platypus and echidna, lack prepuces. The short frenulum, or frenulum breve, is an external genital anomaly, a condition in which the penis frenulum, an elastic band of tissue under the glans penis that connects to the prepuce and helps to retract the prepuce over the glans, is short and restricts the prepuce backward movement. Frenulum breve is described for humans as a congenitally short frenulum of varying degree, restricting the movement, and gliding of the prepuce over the glans, “comparable to tongue tie”. Semen collection attempts were performed with golden lion tamarins, Leontopithecus rosalia, at Fundação Zoológico de São Paulo and Centro de Primatologia do Rio de Janeiro. Using the penile vibrostimulation technique, animals were stimulated and penile curvatures were visualized during erection, preventing a full erection of the penis, in animals from both institutions. Around 70% of all animals had a short frenulum. Curvatures that make copulation impossible may require surgical correction, yet this doesn't seem to be the case for these males, as among them there were individuals proven to be fertile. It is worth to note that short frenulum has never been noticed in the other two species – L. chrysomelas and L. chrysopygus under human care, in erection events during semen collection, and therefore, this seems to be an exclusive feature of L. rosalia. 

Financiadores

Coordenadoria de Fauna Silvestre, Secretaria de Meio Ambiente, Infraestrutura e Logística, São Paulo, SP, Brasil Centro de Primatologia do Rio de Janeiro, Instituto Estadual do Ambiente, Guapimirim, RJ, Brasil

Palavras-chave

Neotropical primates; primate reproduction; frenulum breve