Pathologic Findings and Liver Elements in Hibernating Bats With White-Nose Syndrome

Abstract

Two groups of vespertilionid bats were collected from affected hibernacula. In group 1 (n, 14; pathology and microbiology), the average body weights of all species were at the lower limit of published ranges. Twelve bats (86%) had mycotic growth in the epidermis, hair follicles, and sebaceous glands. Geomyces destructans, with its characteristic curved conidia, was observed microscopically, cultured, and confirmed by polymerase chain reaction. Dermatitis and mural folliculitis was nil to mild. When focally coinfected with Gram-negative bacteria, there was necrosis and pustules. Fat stores were little to abundant in 12 bats (86%) and nil in 2. Thirteen bats (93%) had pulmonary congestion and 7 (50%) had bone marrow granulocytosis. In group 2 (n, 24; liver elements), 3 bats (13%) had potentially toxic lead levels and 1 (4%), potentially toxic arsenic level. There was no evidence of major organ failure or consistent element toxicity.

Specific Alterations in Complement Protein Activity of Little Brown Myotis (Myotis lucifugus) Hibernating in White-Nose Syndrome Affected Sites

“…As of March 2011, presence of G. destructans in North America has been confirmed in 16 states (Connecticut, Delaware, Indiana, Maryland, Massachusetts, Missouri, New Hampshire, New Jersey, New York, North Carolina, Oklahoma, Pennsylvania, Tennessee, Vermont, Virginia, and West Virginia), three Canadian provinces (New Brunswick, Ontario, Quebec) and from nine hibernating bat species. WNS is manifested by some or all of the following symptoms: 1) a cutaneous fungal infection appearing as white, filamentous hyphae with distinct conidia (spores) on the nose, ears, and wing membranes [3], [4], [5], [6]; 2) depleted white and brown fat reserves [3], [7], [8] (Jonathan D. Reichard, unpublished data); 3) ulcerated, necrotic and scarred wing membranes [9]; and 4) atypical behavior causing bats to emerge prematurely from hibernacula in mid-winter (Alan C. Hicks, unpublished data). G. destructans grows on the skin (nose, ears, and wing membranes) of hibernating bats, and laboratory research has revealed that it grows optimally at temperatures characteristic of hibernacula, ranging from 2 to 14°C [3].…”

DNA-based detection of the fungal pathogen Geomyces destructans in soils from bat hibernacula

“…Although aspects of the complex interactions among the disease, the environment and the host remain unknown, characteristic cutaneous infection of hibernating bats by G. destructans is the only consistently identified contributor to WNS , Courtin et al 2010). Little is known about the geographic distribution of G. destructans (Puechmaille et al 2010, Wibbelt et al 2010 or its taxonomic delimitation ), but as with other fungal pathogens of mammals (e.g.…”

Comparison of Radio-Telemetric Home-Range Analysis and Acoustic Detection for Little Brown Bat Habitat Evaluation

“…The hyphae of this WNS-associated fungus is known to penetrate the dermis of affected bats, eroding wing and ear tissue. The hyphae extends into hair follicles and sebaceous glands, compromising their function and eventually reaching the underlying tissue , although no local inflammation or immune response has been reported in this or other hibernating bat species Courtin et al 2010;Gargas et al 2009;Meteyer et al 2009 (Reichard and Kunz 2009). Up to 61% of little brown myotis monitored at two New Hampshire maternity colonies in the summer of 2008 had severe wing damage, presumably from WNS infection or from frost bite in the previous winter (Reichard et al, 2009).…”

“…Wibbelt et al 2010), but there are still unanswered questions about the specific origin of the fungus. Bats that succumb to WNS exhibit lesions on the skin of their wings, face, and ears , Courtin et al 2010, which may persist into the active season on bats that survive hibernation Reichard and Kunz 2009). Bats at WNS-affected sites also appear to deplete their essential fat reserves well before the end of the typical hibernation period (J. D. Reichard, unpublished data).…”