Molecular Detection and Phylogenetic Analysis of Anaplasma spp. in Korean Native Goats from Ulsan Metropolitan City, Korea

Background: Tick-borne diseases (TBDs) can be fatal to humans as well as to animals causing severe economic losses globally to livestock industries. Many countries conduct regular surveillance of TBDs in livestock. Serological and molecular surveillance of TBDs in livestock and humans was carried out in the Republic of Korea. However, there are not a lot of data on analyses of anaplasmosis in Korean native goats and the correlation with rearing methods and seasons. Methods: In this study, goats in Ulsan city were tested for anaplasmosis by PCR and 16S rRNA sequencing. A total of 452 goat blood samples were collected from 20 farms in 2016. The goat farms in Ulsan city had three different types of rearing methods: conventional, confined, and mixed grazing-confined. Results: Forty-nine of the 452 goats (10.8%) were anaplasmosis positive. Sequence analysis of the PCR products from these 49 goats revealed that 39 of 452 goats (8.6%) were Anaplasma bovis positive, and 10 of 452 goats (2.2%) were infected with Anaplasma capra. The highest outbreaks of anaplasmosis occurred in mixed grazing-confined type of farms (27.1%, 33/122) (chi(2) = 60.72, df = 2, p < 0.05), but there was no significant difference in the occurrence of anaplasmosis between spring, summer, and fall seasons. Conclusions: This study was the first detection of A. bovis in Korean native goats and its relationship with rearing methods and seasons. These findings suggested that Korean native goats were highly exposed to Anaplasma spp. during summers when the tick population is the highest and in farms employing mixed grazing-confined rearing methods.