Susceptible trichostrongyloid species mask presence of benzimidazole-resistant Haemonchus contortus in cattle

Parasites & Vectors

Table 6 Mean resistance allele frequencies (%) ± standard deviation for the F167Y, E198A and F200Y single-nucleotide polymorphisms in isotype 1 β-tubulin gene of Haemonchus placei adult worms from cattle at three different study areas in South Darfur State, Sudan

Isolate	No. of pooled samples^a	Codon 167 (TAC)	Codon 198 (GCA)	Codon 200 (TAC)^b	Codon 200 (TAC)^c
Nyala	2	3.00 ± 1.16	12.75 ± 3.10	6.75 ± 1.23	7.50 ± 1.73
Rehed Al-Birdi	3	2.67 ± 0.82	10.50 ± 0.84	5.50 ± 1.38	6.67 ± 0.82
Tulus	3	3.17 ± 0.75	11.33 ± 0.82	5.67 ± 0.52	6.67 ± 0.52
Total	8	2.94 ± 0.85	11.38 ± 1.78	5.88 ± 1.15	6.88 ± 1.03

For each sample, two technical replicates were analysed
^aPools of adult male Haemonchus spp. isolated from cattle abomasa at abattoirs (16–100 worm/sample) with unknown history of anthelmintic treatments
^bPyrosequencing assays conducted with the sequencing primer for codon 198
^cPyrosequencing assays performed with the codon 200 specific sequencing primer

ISSN: 1756-3305