| Summary: | <i>Staphylococcus aureus</i> (<i>S. aureus</i>), a major mastitis pathogen in dairy goats, is classified as a contagious pathogen. Although previous research has shown that extramammary body sites can be colonized with <i>S. aureus</i>, it is unknown whether these sites are reservoirs for intramammary infections. The aim of this research was to determine whether extramammary sites can be colonized with mastitis-associated <i>S. aureus</i> strains in dairy goats. Milk samples were collected from 207 primiparous goats and from 120 of these goats, extramammary site samples (hock, groin, nares, vulva and udder) were collected from a large commercial dairy goat herd in the Netherlands during four sampling visits. Extramammary site swabs and milk samples were (selectively) cultured and <i>S. aureus</i> isolates were <i>spa</i> genotyped. The prevalence of colonization of the extramammary sites at goat level was 51.7% and the prevalence of <i>S. aureus</i> intramammary infections was 7.2%. The nares were colonized most frequently (45%), while the groin area was colonized the least (2.5%). Six <i>spa</i> genotypes were identified in this herd and there was no significant difference in the distribution of <i>spa</i> genotypes between the milk or the extramammary sites (<i>p</i> = 0.141). Both in the extramammary sites and in the milk, <i>spa</i> genotypes t544 (82.3% and 53.3%) and t1236 (22.6% and 33.3%) were the dominant genotypes. These results show that in goats, extramammary sites, particularly the nares, are frequently colonized with mastitis-associated <i>S. aureus</i> strains. Extramammary sites may, thus, be a source of <i>S. aureus</i> intramammary infections that are not targeted by the intervention measures aimed at preventing transmission from infected udder glands.
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