酵母马拉色菌是狗的皮肤和粘膜的常见居民。然而,在某些情况下，这种酵母可以过度生长，并作为导致狗耳炎和皮炎的机会病原体。犬足皮炎是犬中常见的疾病，其中厚皮分枝杆菌是机会性病原体。在本研究中,在治疗前后，从患有足皮炎的狗的指间空间收集的样品中评估并定量了马拉色菌酵母的存在，和健康的狗。对样本进行了两种不同的细胞学检查，在Sabouraud葡萄糖琼脂和改良的Dixon's琼脂上进行培养，并进行靶向内部转录间隔区（ITS）基因组区域的定量PCR。使用核糖体DNA的大亚基的D1D2结构域作为靶标,通过下一代测序(NGS)分析样品的选择。治疗前的足皮炎样本显示出更高的细胞计数，菌落形成单位和ITS拷贝比其余样品。NGS分析显示，子囊是健康和治疗后样品中的主要门。然而,在治疗前的足皮炎样本中，担子菌和厚皮杆菌更为丰富。这些结果通过多种方法支持厚皮杆菌作为犬足皮炎的机会因子，并证明了细胞学和分子定量方法之间的相关性。
The yeast Malassezia pachydermatis is a common inhabitant of the skin and mucosae of dogs. However, under certain circumstances this yeast can overgrow and act as an opportunistic pathogen causing otitis and dermatitis in dogs. Canine pododermatitis is a common disorder in dogs in which M. pachydermatis acts as an opportunistic pathogen. In the present study, the presence of Malassezia yeasts was assessed and quantified in samples collected from the interdigital space of dogs with pododermatitis before and after treatment, and from healthy dogs. The samples were subjected to two different cytological examinations, culture on Sabouraud glucose agar and modified Dixon\'s agar and a quantitative PCR targeting the internal transcribed spacer (ITS) genomic region. A selection of samples was analyzed by next generation sequencing (NGS) using the D1D2 domain of the large subunit of the ribosomal DNA as target. The pododermatitis samples before treatment showed higher cell counts, colony-forming units and ITS copies than the rest of samples. The NGS analysis revealed that Ascomycota was the main phylum in the healthy and post-treatment samples. However, Basidiomycota and M. pachydermatis was more abundant in the pododermatitis samples before treatment. These results support M. pachydermatis as an opportunistic agent in canine pododermatitis by a variety of methods, and demonstrate the correlation between cytologic and molecular methods for quantification.
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