Respiratory disease associated with Bordetella bronchiseptica in a Hoffmann's two-toed sloth (Choloepus hoffmanni)

IDLY INFECTED: A REVIEW OF INFECTIOUS AGENTS IN POPULATIONS OF TWO- AND THREE-TOED SLOTHS (CHOLOEPUS SPECIES AND BRADYPUS SPECIES)

Two- and three-toed sloths (Choloepus spp. and Bradypus spp.) have become popular animals in American culture and in American zoos, where they are frequently used as animal ambassadors. Despite the increased focus on sloth species, the prevalence of infectious diseases in sloth populations and the associated clinical consequences are relatively unknown. This study reviewed all published literature from 1809 to 2019 that examined infectious agents in both captive and wild populations of either two- or three-toed sloths. Online databases were electronically searched for relevant manuscripts using strings of inclusion and exclusion terms, resulting in an initial identification of 5,364 articles. After removing duplications and conducting two relevance screenings, 57 manuscripts were included in the full review. A total of 1,769 individual two-toed sloths and 879 individual three-toed sloths were accounted for in the included studies, with evidence of infection or exposure to infectious agents in 647 (36.6%) and 222 (25.3%) individual two- and three-toed sloths, respectively. Approximately 74% of documented infections were cryptic fungal, parasitic, and viral infections. The remaining 26% of infections represent those that were associated with clinical signs of disease. The infectious agents reported were bacterial (84), parasitic (20), viral (9), and fungal (4). Significant knowledge gaps remain regarding clinical and subclinical infectious disease prevalence and impact in both free-ranging and captive sloths.

SEROLOGIC RESPONSE TO CANINE DISTEMPER VACCINATION IN CAPTIVE LINNAEUS'S TWO-TOED SLOTHS ( CHOLOEPUS DIDACTYLUS) AFTER A FATAL CANINE DISTEMPER VIRUS OUTBREAK

Canine distemper virus (CDV) affects many wild and captive, nondomestic species worldwide but has not been previously reported in Xenarthra. Paucity of information on vaccination safety and efficacy presents challenges for disease prevention in captive collections. CDV infections and subsequent mortalities in five captive Linnaeus's two-toed sloths ( Choloepus didactylus) in eastern Tennessee are reported. Clinical signs included oculonasal discharge, oral ulcerations, and diarrhea, and the diagnosis was confirmed by necropsy, histopathology, immunohistochemistry, virus isolation, and polymerase chain reaction. Viral sequencing identified the strain to be consistent with a new CDV lineage currently affecting domestic dogs and wildlife in Tennessee. Seven sloths were examined and vaccinated using a recombinant CDV vaccine on days 0 and 21. Subsequent blood samples showed increased titers in 3/4 sloths. Based on the outbreak and serologic findings postvaccination without adverse effects, the authors recommend recombinant CDV vaccination in sloths exposed to known carriers of CDV.