First report of psoroptic mange in a herd of llamas (Lama glama) of the Andean region

FABIANA E. SOSA; DIEGO M. MEDINA; JUAN F. MICHELOUD; HUGO M. BORSETTI; NANCY HERNÁNDEZ; LEONHARD SCHNITTGER

VETERINARY RESEARCH COMMUNICATIONS

SPRINGER

Lugar: Berlin; Año: 2024

0165-7380

An outbreak of Psoroptes sp.-caused mange was detected in a llama herd of Larcas, Jujuy province, Argentina. Infested llamas showed alopecia, erythema, hyperpigmentation, hyperkeratosis, and inflammation of the ear pinnae, as well as crusts and serous, serosanguineous, or purulent drainage with an unpleasant smell in the external ear canal. Microscopic evaluation of skin scrapings revealed 0.5 to 0.7 mm-long acari identified as Psoroptes sp. based on their morphology. Histology showed a typical allergic reaction with perivascular to periadnexal mixed inflammatory infiltrate. Cytochrome c oxidase subunit I gene sequences of the acari were closest related to the corresponding sequence from an acari isolate of a bighorn sheep from the US, placing jointly into a single clade of the inferred phylogenetic tree. Furthermore, Psoroptes sequences of isolates from rabbits and bighorn sheep from Canada were placed in a closely related sister clade. Phylogenetic analysis of near-complete cytochrome b sequences showed three well-supported clades, one of which comprised the sequences of acari isolated from the Larcas llamas and US bighorn sheep. This is the first report on Psoroptes sp. infestation of llamas raised in their natural distribution area. Investigations on mange etiological agents infesting South American camelids and their distribution are necessary to implement control strategies to mitigate the negative impacts of these parasitic infections.