Choloepus Research Articles

Systemic Acanthamoeba T17 infection in a free-ranging two-toed sloth: case report and literature review of infections by free-living amebas in mammals.

A free-ranging, adult female two-toed sloth (Choloepus hoffmanni) was brought to a wildlife rescue center in Costa Rica with ocular and auricular myiasis and numerous skin lesions. After one month of unsuccessful systemic and topical antimicrobial treatment, the patient died. A postmortem examination was performed, and tissues were examined histologically, confirming disseminated amebic infection with intralesional trophozoites and cysts in the lungs, liver, eye, heart, spleen, and stomach. Immunohistochemistry identified the ameba as Acanthamoeba sp. A multiplex real-time PCR assay, 18S ribosomal DNA PCR, and sequencing performed on formalin-fixed, paraffin-embedded lung tissue confirmed the Acanthamoeba T17 genotype. The Acanthamoeba genus is in the group of free-living amebas that cause infection in humans and animals, and it is ubiquitous in the environment. Acanthamoeba T17 has been isolated from water and soil, but to our knowledge, this genotype has not been implicated in infections of animals previously and has not been reported from Costa Rica. Systemic Acanthamoeba infection has not been described in sloths previously. We provide a comprehensive literature review describing infections by free-living amebas of the genus Acanthamoeba spp., Balamuthia spp., and Naegleria spp. in domestic, zoo, and wild mammals.

Gender Determination by PCR Assay for The Sex-Determining Region Y(SRY) Gene Amplification in Linnaeus’s Two-Toed Sloth (Choloepus Didactylus)

In Linnaeus’s two-toed sloths (Choloepus didactylus), there is no distinct sexual dimorphism. It is an obstacle for gender determination from the external genitalia, especially in newborns or young sloths. Hence, easy, rapid, and reliable genetics-based methods for gender identification of the sloths are needed to continue captive breeding more successfully. In this study, a PCR-based technique that allows gender determination of two-toed sloths by using a sex-determining region Y (SRY) gene marker was described. The hair samples from young (suspect gender) and adult sloths (known gender) were used in genetic analysis. Initially, genomic DNA was isolated from hair root samples using Roche high pure PCR template preparation kit. The SRY primers were specifically designed based on the NCBI and Ensembl databases, and they were verified with the BLAST program concerning the two-toed sloth genome. PCR amplification with the SRY-specific primers was carried out by a programmable thermal cycler device using FastStart High Fidelity PCR System, Roche dNTPack. The samples were then electrophoresed on 2% agarose gels and were visualized by a gel documentation and analysis system. A specific band in the electrophoresis pattern is diagnostic for a male individual with a partial SRY region. Hence, the analysis demonstrated that the samples belonged to a male two-toed sloth. Two-toed sloth species are commonly preferred animals in zoos. Gender determination is inevitable for these animals in captivity to be raised successfully and healthily. Molecular genetic techniques allow high efficiency in taxonomic evaluations and gender identification in species that do not display sexual dimorphism. The PCR assay described here may be helpful for a rapid genetic analysis that can be widely used in gender determination for two-toed sloths.

The Narial Anatomy of Extinct and Extant Sloths (Xenarthra, Folivora): Osteological Anomalies in the Extant Two-Toed Sloth Choloepus

The Narial Anatomy of Extinct and Extant Sloths (Xenarthra, Folivora): Osteological Anomalies in the Extant Two-Toed Sloth Choloepus

Great powers and UN force generation: a case study of UNAMID

ABSTRACTHow are UN peacekeepers recruited? While we know a lot about UN member states’ general predispositions to participate in UN peacekeeping operations, we know very little about the actual UN force generation process. What role do the UN and its powerful member states play in this process? How do they interact to recruit UN forces? This article seeks answers to these questions by means of an in-depth case study of the force generation process for the UN–AU operation to Darfur (UNAMID). The case study relies on over 50 interviews with high-level decision-makers as well as newly declassified documents from the National Security Archive in Washington, DC. Overall the case study depicts a tantalizing division of labour between the technical expertise of the United Nations and the political power of key UN member states. It appears that UN peacekeeping contributions sometimes require the provision of financial and/or other incentives that go beyond regular UN reimbursements. As a result, powerful UN member states need to step in. However, UN officials play an important brokerage role in this process informing interested UN member states which countries would be suitable for bilateral démarches and why.

Comparative Morphological Examinations of the Cervical and Thoracic Vertebrae and Related Spinal Nerves in the Two-Toed Sloth

The cervical and thoracic regions including vertebrae, spinal nerves, and brachial plexus were examined by macroscopic and three-dimensional computed tomography observational scans in the two-toed sloth (Choloepus didactylus). This species possesses seven cervical vertebrae unlike closely related sloths, which possess varying number of cervical vertebrae ranging from five to ten. The large axis and the partially vestigial third cervical vertebra are morphologically characteristic of C. didactylus. In addition, the spinal nerve branches of C5, C6, C7, C8, and T1 contributed to the brachial plexus, whereas C4 and T2 did not supply nerves to the plexus. Histological data showed that the branches of C5, C6, C7, and C8 were obviously thicker than that of C4 and T1. The most notable observation was that only the two-toed sloth unlike other sloth species is conservative in these morphological characteristics regarding the cervical vertebrae spinal nerves. By comparing the morphological patterns of the cervical and thoracic spine and the brachial plexus of the two-toed sloth with ancestral morphological patterns and related species, which have derived a repatterned and variable morphology of these structures, it is possible to elucidate the morphological evolution of the cervical and thoracic regions in the evolutionary history of these mammals.

The BRICS Fallacy

The term BRICS—referring to the association of emerging economies of Brazil, Russia, India, China, and South Africa—dominated the headlines in March 2013 as Durban hosted the annual group summit. S...

Intertooth Variation of Orthodentine Microwear in Armadillos (Cingulata) and Tree Sloths (Pilosa)

The analysis of orthodentine microwear has recently been established as a proxy for diet in extant and fossil xenarthrans (sloths, armadillos, and their extinct relatives). Previous analyses have relied on standardized comparison of sampling locations between taxa in order to statistically correlate microwear on xenarthran teeth with primary diet; variation in orthodentine microwear across the toothrow and its potential effect on dietary classification in xenarthrans remains unexplored. This study is the 1st to examine intertooth variation of microwear features in extant xenarthrans to test the necessity of standardized tooth comparison in orthodentine microwear analysis of paleodiet in fossil taxa. Statistical mean correlation tests were used to compare microwear variables between different sampling locations in a series of upper and lower teeth in 4 extant xenarthran species (Bradypus tridactylus [pale-throated three-toed sloth], Choloepus didactylus [Linnaeus' two-toed sloth], Dasypus novemcinctus [nine-banded armadillo], and Euphractus sexcinctus [six-banded armadillo]) and showed that microwear distribution between sampling locations is more conserved in three-toed sloths relative to two-toed sloths and armadillos. Significant variation in the latter groups may stem from uneven distribution of bite-force on the dentition in long-faced animals (two-toed sloths and armadillos) relative to short-faced animals (three-toed sloths), although food texture and intraspecific variation in diet may play a role as well. Based on results from extant taxa, standardized tooth comparison is required for analysis of paleodiet in glyptodonts and pampatheres and also is recommended for ground sloths in future studies of microwear.

Hand‐rearing a Two‐toed sloth

This article describes the hand‐rearing of a ♀ Two‐toed sloth Choloepus didactylus from birth to its death at the age of 10 months. Developmental issues are discussed in detail, including diet, health, growth and weaning. The infant was successfully introduced to an adult ♀ in preparation for long‐term pairing with a young 3. Socialization, integration and imprinting issues are also discussed. Retrospective analysis concluded that this was a worthwhile hand‐rearing exercise that may he of benefit to others maintaining the species.

Vision of Two-Toed Sloths (Choloepus)

Vision of Two-Toed Sloths (Choloepus)

Toxoplasmosis of the Two-Toed Sloth, Choloepus didactylus, in Brazil

Toxoplasmosis of the Two-Toed Sloth, Choloepus didactylus, in Brazil

Leishmania braziliensis isolated from sloths in Panama.

Two edentates, the twotoed sloth Choloepus hoffmanni and the three-toed sloth Bradypus infuscatus, infected with Leishmania were found in Panama. The rates of infection were 14.1 and 1.3 percent in Choloepus and Bradypus, respectively. Leishmania braziliensis sensu lato was cultured from skin, blood, spleen, liver, or bone marrow of 13 sloths often from two or more tissues from the same animal. This strain is indistinguishable from Leishmania strains isolated from hunmanis in Panama.

The Gestation Period of the Two-Toed Sloth

An observation of minimal gestation period for a single specimen of the two-toed sloth, Choloepus didactylus , was recorded at the Detroit Zoological Park. Asdell (patterns of mammalian reproduction, 1946) reports the gestation period of a species of three-toed …

Note on the Blood-Corpuscles of the Two-Toed Sloth, Cholœpus Didactylus

ABSTRACT MR. H. N. Moseley, of Exeter College, called my attention a few days ago to the appearance of nucleation which a slide of the dried blood-corpuscles of the Two-toed Sloth, Cholœpus didactylus, presented under a quarter-of-an-inch object-glass of Powell and Lealand’s. I had a short time before met with a statement in the recently published second part of Dr. Kühne’s ‘Lehrbuch der Physiologischen Chemie,’ p. 195,‡ to the effect that only some mammals, the sloth and the camel, possessed nucleated blood-corpuscles. And this coincidence determined me to use such means as we had at our disposal for settling a point as to which all recent authorities were, as far as my knowledge went, opposed to Dr. Kühne.