title: Characterization of Prototheca zopfii Genotypes Isolated from Cases of Bovine Mastitis and Cow Barns in China.
abstract: Protothecal mastitis, caused mostly by Prototheca zopfii (P. zopfii), is increasing in dairy herds and is being reported globally. The present study was aimed at studying the epidemiology of mastitis and at molecular characterization of P. zopfii isolates from dairy herds and their surroundings in three provinces of China using microbiological, biochemical and molecular methods, and antibiotic susceptibility tests. Samples from milk (n = 620) of mastitic cows and their barns sources (n = 410) including feces, feed, bedding materials and drinking water were analyzed. Among other pathogens recovered from mastitic milk, 84 (13.5%) of the isolates were identified as P. zopfii. All of the P. zopfii isolates recovered from milk were recognized as genotype 2, whereas 58 (73.4%) and 21 (26.6%) isolates from environmental sources were found to be P. zopfii genotypes 1 and 2, respectively. The isolates were susceptible to some antibiotics and antifungal agents, including amikacin (78.1%), streptomycin (58.5%), gentamicin (17.8%), amphotericin B (68.6%) and nystatin (64.4%). Additionally, the two genotypes displayed versatile patterns of susceptibility to different antimicrobials agents. Phylogeny of the genotypes on the basis of 18S SSU rDNA and 28S SSU rDNA was also investigated. The isolates of the two genotypes separated into different clades, and no interrelationship was observed among these as shown by phylogenetic analysis. The genotype 1 isolates from cow barn sources were non-pathogenic and may not present any risk of mastitis. We conclude that P. zopfii genotype 2 might play an important role in bovine mastitis in China.
authors.affiliation: College of Veterinary Medicine, China Agricultural University, Yuan Ming Yuan West Road No. 2, Haidian District, 100193, Beijing, People's Republic of China.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Shahid
authors.affiliation: College of Veterinary Medicine, China Agricultural University, Yuan Ming Yuan West Road No. 2, Haidian District, 100193, Beijing, People's Republic of China.
authors.forename: Tariq
authors.initials: T
authors.lastname: Ali
authors.affiliation: College of Veterinary Medicine, China Agricultural University, Yuan Ming Yuan West Road No. 2, Haidian District, 100193, Beijing, People's Republic of China.
authors.forename: Limei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: College of Veterinary Medicine, China Agricultural University, Yuan Ming Yuan West Road No. 2, Haidian District, 100193, Beijing, People's Republic of China.
authors.forename: Rongguang
authors.initials: R
authors.lastname: Hou
authors.affiliation: College of Veterinary Medicine, China Agricultural University, Yuan Ming Yuan West Road No. 2, Haidian District, 100193, Beijing, People's Republic of China.
authors.forename: Shiyao
authors.initials: S
authors.lastname: Zhang
authors.affiliation: College of Veterinary Medicine, China Agricultural University, Yuan Ming Yuan West Road No. 2, Haidian District, 100193, Beijing, People's Republic of China.
authors.forename: Laidi
authors.initials: L
authors.lastname: Ding
authors.affiliation: College of Veterinary Medicine, China Agricultural University, Yuan Ming Yuan West Road No. 2, Haidian District, 100193, Beijing, People's Republic of China.
authors.forename: Dandan
authors.initials: D
authors.lastname: Han
authors.affiliation: College of Veterinary Medicine, China Agricultural University, Yuan Ming Yuan West Road No. 2, Haidian District, 100193, Beijing, People's Republic of China.
authors.forename: Zhaoju
authors.initials: Z
authors.lastname: Deng
authors.affiliation: Faculty of Animal and Veterinary Sciences, University of Agriculture Peshawar, Peshawar, Pakistan.
authors.forename: Abdur
authors.initials: A
authors.lastname: Rahman
authors.affiliation: College of Veterinary Medicine, China Agricultural University, Yuan Ming Yuan West Road No. 2, Haidian District, 100193, Beijing, People's Republic of China. hanbo@cau.edu.cn.
authors.forename: Bo
authors.initials: B
authors.lastname: Han
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000494:pharmacology*; D002417:Cattle; D002681:China; D003612:Dairying; D005260:Female; D005838:Genotype; D008414:Mastitis, Bovine / Q000453:epidemiology*; D008892:Milk; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D011525:Prototheca / Q000145:classification / Q000187:drug effects* / Q000235:genetics* / Q000302:isolation & purification; D012337:RNA, Ribosomal, 18S / Q000235:genetics*
chemical_list: D000890:Anti-Infective Agents; D012337:RNA, Ribosomal, 18S
keywords: Antibiotic susceptibility; Bovine mastitis; Genotyping; Phylogenetic tree; Prototheca zopfii