Instituto de Investigación y Desarrollo Tecnológico para la Agricultura Familiar - Región NOA (IPAF NOA), Centro de Investigación y Desarrollo Tecnológico para la Agricultura Familiar (CIPAF), Instituto Nacional de Tecnología Agropecuaria (INTA), 4624, Hornillos, Argentina.
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), C1425FQB, Buenos Aires, Argentina.
Parasitol Res. 2024 Sep 28;123(9):334. doi: 10.1007/s00436-024-08357-0.
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 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. Phylogenetic tree analysis showed that the cytochrome c oxidase subunit I gene sequences analyzed from the sampled acari clustered into a single P. ovis clade including sequences isolated from rabbits and bighorn sheep, with P. natalensis as a sister taxon that infested bighorn sheep from the USA. Phylogenetic analysis of cytochrome b sequences showed three well-supported clades, one of which contained the sequences of the Larcas llamas and US bighorn sheep isolates. This is the first report on P. ovis infestation of llamas raised in their original location. Investigations on mange etiological agents acting on South American camelids and their distribution are necessary to implement control strategies to mitigate the negative impacts of these parasitic infections.
在阿根廷胡胡伊省的拉卡拉斯，暴发了一起由皮蝇属引起的痒螨病。受感染的羊驼出现脱毛、红斑、色素沉着、过度角化以及耳部耳甲红肿，还有在外耳道结痂和出现浆液性、血脓性或脓性渗出物，并带有难闻气味。皮肤刮片的显微镜评估显示，长 0.5-0.7 毫米的螨虫被鉴定为皮蝇属，这是基于它们的形态学特征。组织学显示出一种典型的过敏反应，伴有血管周围到附器周围混合性炎症浸润。系统发育树分析显示，从采样的螨虫中分析的细胞色素 c 氧化酶亚基 I 基因序列聚成一个单一的绵羊痒螨进化枝，其中包括从兔子和大角羊分离出的序列，亲缘关系最近的是感染美国大角羊的亲缘种纳塔尔痒螨。细胞色素 b 序列的系统发育分析显示出三个支持度较高的进化枝，其中一个进化枝包含拉卡拉斯羊驼和美国大角羊分离株的序列。这是首次报道绵羊痒螨感染原产于其所在地的羊驼。有必要对作用于南美驼羊的痒螨病因进行调查，并对其分布情况进行调查，以实施控制策略，减轻这些寄生虫感染的负面影响。
