Further characterisation of a triple resistant field isolate of Teladorsagia from a Scottish lowland sheep farm

被引:27
作者
Bartley, DJ
Jackson, E
Sargison, N
Jackson, F
机构
[1] Moredun Res Inst, Dept Parasitol, Penicuik EH26 0PZ, Midlothian, Scotland
[2] Royal Dick Sch Vet Studies, Easter Bush Vet Ctr, LAPTU, Roslin EH25 9RG, Midlothian, Scotland
关键词
anthelmintics; assay; benzimidazole; efficacy; in vivo; ivermectin; levamisole; moxidectin; resistance; Teladorsagia circumcincta;
D O I
10.1016/j.vetpar.2005.07.017
中图分类号
R38 [医学寄生虫学]; Q [生物科学];
学科分类号
07 ; 0710 ; 09 ; 100103 ;
摘要
Anthelmintic efficacies against juvenile developing populations of Teladorsagia species that were known to be resistant to anthelmintics from all three broad spectrum families were examined using a controlled efficacy test. Fenbendazole (FBZ), levamisole (LEV), ivermectin (IVM), combinations of these anthelmintics and moxidectin (MOX) were assessed in parasite naive lambs artificially infected with 8000 third stage larvae (Tci5) and treated orally 8-day post-infection with the compounds at the manufacturers recommended dose rates, FBZ, 5 mg/kg body weight (BW); LEV, 7.5 mg/kg 13W; IVM, 0.2 mg/kg BW; MOX (0.2 mg/kg 13W). The lambs were slaughtered 14-day post-treatment. The arithmetic mean worm burden reductions resulting from oral treatments with FBZ; IVM; LEV; FBZ + lVM; FBZ + LEV; FBZ, LEV + lVM or MOX were 36%, 82%, 38%, 86%, 60%. 88% and 97%, respectively. The results illustrate that combination treatments showed improved efficacies against the juvenile population compared to individually administered treatments but that these improvements were not wholly effective. Moxidectin was the only treatment that was over 95% effective, though caution should be noted when advising the use of MOX prophylactically since 3% of the infection still survived this treatment. Treatments directed at juvenile stages of Tci5 were less effective, with the exception of lVM, compared to a similar trial using Tci5 where the same treatments were directed against a predominantly adult population. No interaction was detected comparing the timings of treatments and its effectiveness with the exception of IVM (two-way ANOVA, p < 0.05). These findings suggest that, on the whole, the selection processes for anthelmintic resistance (AR) may occur at an early stage of development within the parasites, having severe implications for the early detection of AR. (c) 2005 Elsevier B.V. All fights reserved.
引用
收藏
页码:261 / 266
页数:6
相关论文
共 25 条
[1]   THE EFFICACY OF MIXTURES OF ALBENDAZOLE SULFOXIDE AND LEVAMISOLE AGAINST SHEEP NEMATODES RESISTANT TO BENZIMIDAZOLE AND LEVAMISOLE [J].
ANDERSON, N ;
MARTIN, PJ ;
JARRETT, RG .
AUSTRALIAN VETERINARY JOURNAL, 1991, 68 (04) :127-132
[2]   Characterisation of two triple resistant field isolates of Teladorsagia from Scottish lowland sheep farms [J].
Bartley, DJ ;
Jackson, F ;
Jackson, E ;
Sargison, N .
VETERINARY PARASITOLOGY, 2004, 123 (3-4) :189-199
[3]   WORLD-ASSOCIATION-FOR-THE-ADVANCEMENT-OF-VETERINARY-PARASITOLOGY (WAAVP) METHODS FOR THE DETECTION OF ANTHELMINTIC RESISTANCE IN NEMATODES OF VETERINARY IMPORTANCE [J].
COLES, GC ;
BAUER, C ;
BORGSTEEDE, FHM ;
GEERTS, S ;
KLEI, TR ;
TAYLOR, MA ;
WALLER, PJ .
VETERINARY PARASITOLOGY, 1992, 44 (1-2) :35-44
[4]   EFFICACY OF MOXIDECTIN AGAINST AN IVERMECTIN-RESISTANT STRAIN OF HAEMONCHUS-CONTORTUS IN SHEEP [J].
CRAIG, TM ;
HATFIELD, TA ;
PANKAVICH, JA ;
WANG, GT .
VETERINARY PARASITOLOGY, 1992, 41 (3-4) :329-333
[5]  
DENHAM D A, 1969, Journal of Helminthology, V43, P299, DOI 10.1017/S0022149X00004855
[6]   RESPONSE TO IVERMECTIN TREATMENT OF PARASITIC STAGES OF HAEMONCHUS-CONTORTUS RESISTANT OR SUSCEPTIBLE TO IVERMECTIN [J].
ECHEVARRIA, FAM ;
ARMOUR, J ;
BORBA, MF ;
DUNCAN, JL .
JOURNAL OF PARASITOLOGY, 1992, 78 (05) :894-898
[7]   Sequences of beta-tubulin cDNA from benzimidazole-susceptible and -resistant strains of Teladorsagia circumcincta, a nematode parasite of small ruminants [J].
Elard, L ;
Comes, AM ;
Humbert, JF .
MOLECULAR AND BIOCHEMICAL PARASITOLOGY, 1996, 79 (02) :249-253
[8]   Cloning, sequencing, and developmental expression levels of a novel glutamate-gated chloride channel homologue in the parasitic nematode Haemonchus contortus [J].
Forrester, SG ;
Hamdan, FF ;
Prichard, RK ;
Beech, RN .
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 1999, 254 (03) :529-534
[9]   Avermectin/milbemycin resistance in trichostrongyloid nematodes [J].
Gill, JH ;
Lacey, E .
INTERNATIONAL JOURNAL FOR PARASITOLOGY, 1998, 28 (06) :863-877
[10]   SELECTION OF IVERMECTIN-RESISTANT TRICHOSTRONGYLUS-COLUBRIFORMIS IN LAMBS [J].
GIORDANO, DJ ;
TRITSCHLER, JP ;
COLES, GC .
VETERINARY PARASITOLOGY, 1988, 30 (02) :139-148