A case of polydactyly in a wild brown howler monkey (Alouatta guariba clamitans)

DA SILVA, MA; -STEINBERG, E.R.;; PASKULIN, G; DOS SANTOS TEXEIRA, F; DE SOUZA JESUS, A; M.D. MUDRY,; BICCA MARQUES, JC

Recife, Pernambuco, Brasil

Congreso; II Congreso Latinoamericano XV Congreso Brasilero de Primatología.; 2013

Sociedad Latinoamericana de Primatología, Sociedad Brasilera de Primatología

Polydactyly, the presence of extra digits in hands and/or feet, is a congenital physical anomaly reported for apes (Homo sapiens, Pan troglodytes, Pongo sp.,Hylobates sp. and Symphalangus syndactylus), Old World monkeys (Nasalis larvatus,Presbytis entellus, Papio hamadryas, Macaca fascicularis, M. fuscata and M. mulatta),New World monkeys (Callithrix jacchus and Saguinus oedipus) and prosimians (Lemur catta). In humans it has been related to several causes, including the trisomy of chromosome 13 (HSA13). Here we report the first case of polydactyly in an atelid, the brown howler monkey Alouatta guariba clamitans (AGU). A wild dependent infant female (16 weeks old; age estimation based on body size, weight and dentition) taken by a domestic dog after falling to the ground in a ca. 15 ha forest fragment (30º11.81´S, 51º06.39?W) near Estrada Canta Galo, Porto Alegre, State of Rio Grande do Sul, Brazil, in 15 April 2012 was rescued and survived. The infant presented bilateral preaxial polydactyly (seven digits) in both feet. The individual did not move the lower limbs and feet. The examination of a radiological print showed highly deformed (bowing and shortened) right tibia and fibula, a growth plate fracture of the right knee, and shortened and fused phalanges of the left hallux. No change in the vertebral column was found. A karyological analysis of peripheral blood lymphocyte culture showed that 12 out of 15 (80%) G-banded mitotic metaphases presented normal karyotype (2n=46,XX). The remaining three metaphases (20%) exhibited numerical chromosomal rearrangements, including two (13%) with a trisomy of AGU chromosome #13 (AGU13). Comparative karyology showed that HSA13 shares homeology to AGU13. The infant died in captivity on 2 November 2012. Histopathology showed acute interstitial pneumonia, intense congestion, interstitial suppurative nephritis with interstitial necrosis and pyelonephritis as the possible causes of death.