Veterinarski arhiv, Vol. 88 No. 3, 2018.
Izvorni znanstveni članak
https://doi.org/10.24099/vet.arhiv.170318a
Variation in the β-tubulin isotype 1 gene at codon 167 and 200 responsible for benzimidazole resistance in Haemonchus contortus in sheep of Krishna District, AP, India
Kaplaywar Sathish
; Department of Veterinary Parasitology, NTR College of Veterinary Science, Sri Venkateswara Veterinary University, Gannavaram, Andhra Pradesh, India
Chennuru Sreedevi
; Department of Veterinary Parasitology, NTR College of Veterinary Science, Sri Venkateswara Veterinary University, Gannavaram, Andhra Pradesh, India
Krovvidi Sudhakar
orcid.org/0000-0003-2054-8607
; Department of Veterinary Parasitology, NTR College of Veterinary Science, Sri Venkateswara Veterinary University, Gannavaram, Andhra Pradesh, India
Pattipati Malakondaiah
; Department of Veterinary Parasitology, NTR College of Veterinary Science, Sri Venkateswara Veterinary University, Gannavaram, Andhra Pradesh, India
G. S. Rao
; Department of Veterinary Parasitology, NTR College of Veterinary Science, Sri Venkateswara Veterinary University, Gannavaram, Andhra Pradesh, India
Sažetak
A study was carried out for detection of single nucleotide polymorphisms at codon 167 and 200 of the β-tubulin isotype 1 gene that are linked to BZ resistance of Haemonchus contortus in sheep. A total of 226 adult male worms were genotyped from different regions of Krishna district, Andhra Pradesh. Amplification of DNA from each worm by PCR, followed by semi-nested PCR, yielded an expected fragment of 488 bp product. The PCR product was subsequently digested with restriction endonuclease SnaBI and TaaI to detect mutation at codon 167 and 200 respectively. On digestion, three different fragment patterns were observed at codon 200, one with 215 bp, 206 bp and 67 bp (homozygous resistant; ‘rr’), the second with 282 bp, 215 bp, 206 bp and 67 bp (heterozygous; ‘rS’), and another with 282 bp and 206 bp fragment (homozygous susceptible; ‘SS’). No resistance allele (TAC) was evident at codon 167 in any worms including the worms that carried a susceptible allele (TTC) at codon 200. The overall genotype frequencies varied significantly (P<0.01) with respect to the β-tubulin gene/TaaI locus in the study area. The frequency of ‘rS’ (64.60%) genotypes was high compared to that of ‘rr’ and ‘SS’ genotypes. The genotype frequency for ‘rr’ worms ranged from 6.25% to 31.82% among different regions. In general, the prevalence of BZ resistance allele was found to be significantly (P<0.01) higher (54.0%). Results revealed β-tubulin isotype 1 polymorphism at codon 200 in H. contortus of sheep indicating the occurrence of resistance allele in the study area.
Ključne riječi
Haemonchus contortus; benzimidazole resistance; β-tubulin gene polymorphism; PCR-RFLP
Hrčak ID:
202676
URI
Datum izdavanja:
4.6.2018.
Posjeta: 923 *