Genetic evidence for hybridisation between Haemonchus contortus and Haemonchus placei in natural field populations and its implications for interspecies transmission of anthelmintic resistance

Chaudhry, Umer; Redman, Elizabeth; Abbas, Muhammad; Raman, Muthusamy; Ashraf, Kamran; Gilleard, John S.

doi:10.1016/j.ijpara.2014.09.002

Cited by 56 publications

(59 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In all cases, H. placei sequences contained P24 (G), P205 (A), P219 (G) confirming SNPs (Table 2 and Figure 2) previously identified by Stevenson et al (1995) and Chaudhry et al (2014). In addition to confirming the three species-specific fixed SNPs, there were 4 sites that showed intraspecific variation in H. placei at position 65,111, 125 and 148 (Table 2).…”

Section: Journal Of Infection and Molecularsupporting

confidence: 75%

“…The results demonstrate three species specific SNPs [P24 (G), P205 (A), P219 (G)] and four intra-specific variations sites at position 65,111, 125 and 148 in H. placei (Table 2). Of those, position 65, 123 and 148 have been previously shown in H. placei (Stevenson et al, 1995;Chaudhry et al, 2014). However position 111 polymorphic site had not been identified previously, so we hypothesized that P111 is a new intra-specific variation present in H. placei from Pakistani region.…”

Section: Journal Of Infection and Molecularmentioning

confidence: 87%

“…For example, the separate species status of H. placei and H. contortus was supported by ITS-2 data, where three fixed nucleotide differences at position 24, 205 and 219 were reported by Stevenson et al (1995) and Chaudhry et al (2014). There have only been a few documented studies on the genetic variation within the isolates of H. placei, however the variations within H. contortus ranged between 4.0 to 5.2% (Heise et al, 1999;Stevenson et al, 1995 andChaudhry et al, 2014). Genetic characterization is important for accurate identification and effective control due to the anthelmintic resistance problem in this nematode (Gasser, 2006).…”

mentioning

confidence: 93%

“…Thus the ITS-2 gene has been widely applied in species identification within the genus Haemonchus (Gasser, 1999;Heise et al, 1999). For example, the separate species status of H. placei and H. contortus was supported by ITS-2 data, where three fixed nucleotide differences at position 24, 205 and 219 were reported by Stevenson et al (1995) and Chaudhry et al (2014). There have only been a few documented studies on the genetic variation within the isolates of H. placei, however the variations within H. contortus ranged between 4.0 to 5.2% (Heise et al, 1999;Stevenson et al, 1995 andChaudhry et al, 2014).…”

mentioning

confidence: 99%

“…However this study was based on just two H. placei and eight H. contortus worms obtained from cattle and sheep respectively. Consequently, Chaudhry et al (2014) further provided that these inter-species differences were fixed when larger numbers of individuals from geographically diverse populations were examined. In the present study, allele-specific PCR primers were developed based on P24 and P219 SNPs, which will then be used to identify Haemonchus populations for the presence of H. placei.…”

mentioning

confidence: 99%

See 4 more Smart Citations

Genetic Variation in the rDNA ITS-2 Sequence of Haemonchus placei from Cattle Host

Ali¹

2015

J. Inf. Mol. Biol.

View full text Add to dashboard Cite

Section: Journal Of Infection and Molecularsupporting

confidence: 75%

Section: Journal Of Infection and Molecularmentioning

confidence: 87%

mentioning

confidence: 93%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 3 more Smart Citations

Genetic Variation in the rDNA ITS-2 Sequence of Haemonchus placei from Cattle Host

Ali¹

2015

J. Inf. Mol. Biol.

View full text Add to dashboard Cite

Worms (Helminths)

Mehlhorn¹

2016

Animal Parasites

View full text Add to dashboard Cite

Absence of detectable benzimidazole-resistance associated alleles in Haemonchus placei in cattle in Nigeria revealed by pyrosequencing of β-tubulin isotype 1

et al. 2015

View full text Add to dashboard Cite

Trichostrongyles are gastrointestinal parasites that occur globally and can cause subclinical to severe, sometimes life-threatening, infections in ruminants, particularly young animals. Benzimidazoles (BZ) are commonly used for the treatment of gastrointestinal parasites in ruminants. Increasing spread of worm populations with anthelmintics resistance has been reported and is considered a consequence of highly frequent and longstanding use of anthelmintics. To obtain initial information regarding the occurrence of putatively BZ-resistant Nigerian Haemonchus populations, screening based on the molecular analysis of BZ-resistance-associated β-tubulin isotype 1 gene sequence polymorphisms was undertaken. Genomic DNA was isolated from pooled adult Haemonchus sp. from 35 animals from each of the six states of southwestern Nigeria. Sequencing of internal transcribed spacer 2 (ITS-2) and external transcribed spacer (ETS) regions was used to determine the Haemonchus species. Pyrosequencing assays were used for detection of single-nucleotide polymorphisms (SNPs) in the β-tubulin isotype 1 genes of the worms at codons 200 and 167 (TTC/TAC) or 198 (GAA/GCA). Exclusively, Haemonchus placei was detected and allele frequencies obtained at all three positions showed no evidence for the presence of resistance-related alleles. For Lagos State, pools of 10 worms from 30 different animals were analyzed separately for the codon 200 SNP, successfully excluding the presence of resistance-associated SNPs in very low frequencies. These positive findings, showing absence of elevated frequencies of BZ-resistance-associated β-tubulin alleles, have considerable significance since it suggests that farmers can still rely on the efficacy of this important drug class when used for controlling trichostrongyle infections in cattle in Nigeria.

show abstract

Genetic evidence for hybridisation between Haemonchus contortus and Haemonchus placei in natural field populations and its implications for interspecies transmission of anthelmintic resistance

Cited by 56 publications

References 50 publications

Genetic Variation in the rDNA ITS-2 Sequence of Haemonchus placei from Cattle Host

Genetic Variation in the rDNA ITS-2 Sequence of Haemonchus placei from Cattle Host

Worms (Helminths)

Absence of detectable benzimidazole-resistance associated alleles in Haemonchus placei in cattle in Nigeria revealed by pyrosequencing of β-tubulin isotype 1

Contact Info

Product

Resources

About