caa a22 4500 445340738 CHVBK 20180317142811.0 cr unu---uuuuu 170323e20111001xx s 000 0 eng 10.1007/s00436-011-2426-0 doi (NATIONALLICENCE)springer-10.1007/s00436-011-2426-0 β-Tubulin genotypes in six species of cyathostomins from anthelmintic-naive Przewalski and benzimidazole-resistant brood horses in Ukraine [Elektronische Daten] [William Blackhall, Tetyana Kuzmina, Georg von Samson-Himmelstjerna] Resistance to benzimidazoles (BZ) in the gastrointestinal nematodes of livestock is characterised by the presence of specific polymorphisms in the β-tubulin isotype 1 protein, a component of microtubules. The most prevalent polymorphism associated with resistance in nematodes infecting cattle, sheep, and goats is found at codon 200, with minor occurrences of polymorphisms at codons 167 and 198. In the cyathostomins that infect horses, however, a polymorphism at codon 167 appears to be more common than the codon 200 polymorphism. In the present study, a focussed analysis of PCR-amplified β-tubulin fragments incorporating the above-mentioned three polymorphic sites in isotype 1 and 2 genes in worms of six species of cyathostomins, Cylicocyclus nassatus, Cylicocyclus ashworthi, Cyathostomum catinatum, Cylicostephanus goldi, Cylicostephanus longibursatus, and Coronocyclus coronatus, was performed. Worms were collected from two distinct horse populations, i.e. they were collected from Przewalski horses of the Askania-Nova Biosphere Reserve that had never received any anthelmintic treatment and from brood horses of the Dubrovsky farm where benzimidazole resistance had become established. DNA was extracted and sequenced from three worms of each species and population as well as from pools of 50 male C. nassatus and C. catinatum from both populations. The vast majority of putatively BZ resistance-associated TAC alleles were found at codon 167, compared to codon 200. The former allele occurred in isotype 1 in all six species of the supposedly benzimidazole-resistant cyathostomins from Dubrovsky horses. None of the polymorphisms associated with resistance was found in the corresponding isotype 2 codons nor at codon 198 in any of the six species of cyathostomins (neither single nor pooled worm DNA) from either of the two populations. These findings further support the predominant association of β-tubulin isotype 1 and therein codon 167 with BZ resistance in cyathostomins. Springer-Verlag, 2011 Blackhall William Global BioEditing, Toronto, ON, Canada aut Kuzmina Tetyana Department of Parasitology, Schmalhausen Institute of Zoology, National Academy of Sciences of Ukraine, 01601, Kyiv, Ukraine aut von Samson-Himmelstjerna Georg Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Königsweg 67, 14163, Berlin, Germany aut Parasitology Research Springer-Verlag 109/4(2011-10-01), 1199-1203 0932-0113 109:4<1199 2011 109 436 https://doi.org/10.1007/s00436-011-2426-0 text/html Onlinezugriff via DOI 1 brief-communication jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00436-011-2426-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Blackhall William Global BioEditing, Toronto, ON, Canada aut NATIONALLICENCE 700 1- Kuzmina Tetyana Department of Parasitology, Schmalhausen Institute of Zoology, National Academy of Sciences of Ukraine, 01601, Kyiv, Ukraine aut NATIONALLICENCE 700 1- von Samson-Himmelstjerna Georg Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Königsweg 67, 14163, Berlin, Germany aut NATIONALLICENCE 773 0- Parasitology Research Springer-Verlag 109/4(2011-10-01), 1199-1203 0932-0113 109:4<1199 2011 109 436 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer