PRODUCTION AND MANAGEMENT: Short Communication| Volume 36, ISSUE 4, P550-555, August 2020

Download started.


Evaluation of parasite resistance in a beef cattle operation with use of extended-release eprinomectin for 3 years



      Our objective was to determine whether parasite resistance to extended-release eprinomectin was present in an operation after 3 yr of eprinomectin use.

      Materials and Methods

      Fall-born Angus × Simmental heifers (224 ± 22 d of age; 171 ± 17.8 kg initial BW) were stratified by d −2 fecal egg count (FEC) and BW and assigned to 1 of 9 groups (7 heifers per group). Groups were then assigned to 1 of 3 treatments: extended-release eprinomectin (ERE; n = 3), extended-release eprinomectin and oxfendazole (ERE+O; n = 3), or saline control (CON; n = 3). Throughout the experiment, FEC and packed cell volume were evaluated 6 times, and a fecal egg reduction test was conducted on d 28.

      Results and Discussion

      There was a treatment × time interaction (P < 0.01) for FEC as FEC was not different on d −2 and 28. However, CON had greater FEC than ERE and ERE+O on d 55 and 83. Additionally, at d 55 ERE had greater FEC than ERE+O. On d 112 and 167, FEC was similar among all treatments. Fecal egg reduction for ERE and ERE+O were above the 90% threshold (91 and 98% reduction, respectively). There was no treatment × time interaction or treatment effect (P ≥ 0.14) for packed cell volume.

      Implications and Applications

      Based on the fecal egg reduction test (>90%), parasite resistance was not present in an operation after 3 yr of use of extended-release eprinomectin.

      Key words

      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


      1. Great Britain, Ministry of Agriculture, Fisheries and Food. 1977. Manual of Veterinary Parasitological Laboratory Techniques. 2nd ed. Her Majesty’s Stationery Office, London, UK.

      2. Backes, E. A. 2016. Evaluation of long-acting eprinomectin compared to conventional anthelmintics in cow/calf production. PhD Diss. Univ. Arkansas, Fayetteville.

        • Bartley D.
        • Jackson F.
        • Jackson E.
        • Sargison N.
        Characterisation of two triple resistant field isolates of Teladorsagia from Scottish lowland sheep farms..
        Vet. Parasitol. 2004; 123: 189-199
        • Coles G.
        • Bauer C.
        • Borgsteede F.
        • Geerts S.
        • Klei T.
        • Taylor M.
        • Waller P.
        World Association for the Advancement of Veterinary Parasitology (WAAVP) methods for the detection of anthelmintic resistance in nematodes of veterinary importance..
        Vet. Parasitol. 1992; 44: 35-44
        • Craig T.M.
        Impact of internal parasites on beef cattle..
        J. Anim. Sci. 1988; 66: 1565-1569
        • DeRouen S.
        • Miller J.
        • Foil L.
        • Gentry G.
        Control of horn flies (Haematobia irritans) and gastrointestinal parasites and its relation with cow-calf performance..
        Vet. Parasitol. 2009; 162: 320-326
        • Edmonds M.
        • Johnson E.
        • Edmonds J.
        Anthelmintic resistance of Ostertagia ostertagi and Cooperia oncophora to macrocyclic lactones in cattle from the western United States..
        Vet. Parasitol. 2010; 170: 224-229
        • Edmonds M.
        • Vatta A.
        • Marchiondo A.
        • Vanimisetti H.
        • Edmonds J.
        Concurrent treatment with a macrocyclic lactone and benzimidazole provides season long performance advantages in grazing cattle harboring macrocyclic lactone resistant nematodes..
        Vet. Parasitol. 2018; 252: 157-162
      3. FASS. 2010. Guide for the Care and Use of Agricultural Animals in Agricultural Research and Teaching. FASS Inc., Champaign, IL.

        • Forbes A.B.
        LongRange (eprinomectin 5%) extended-release injection parasiticide and the utility of extended-activity antiparasitics in cattle..
        Vet. Parasitol. 2013; 192: 308-312
        • Gasbarre L.C.
        Anthelmintic resistance in cattle nematodes in the US..
        Vet. Parasitol. 2014; 204: 3-11
        • Gasbarre L.C.
        • Smith L.L.
        • Lichtenfels J.R.
        • Pilitt P.A.
        The identification of cattle nematode parasites resistant to multiple classes of anthelmintics in a commercial cattle population in the US..
        Vet. Parasitol. 2009; 166: 281-285
        • Kumar N.
        • Rao T.K.
        • Varghese A.
        • Rathor V.S.
        Internal parasite management in grazing livestock..
        J. Parasit. Dis. 2013; 37: 151-157
        • Kunkle B.N.
        • Williams J.C.
        • Johnson E.G.
        • Stromberg B.E.
        • Yazwinski T.A.
        • Smith L.L.
        • Yoon S.
        • Cramer L.G.
        Persistent efficacy and production benefits following use of extended-release injectable eprinomectin in grazing beef cattle under field conditions..
        Vet. Parasitol. 2013; 192: 332-337
      4. Lawrence, J. D., and M. A. Ibarburu. 2007. Economic analysis of pharmaceutical technologies in modern beef production. Proceedings of the NCCC-134 Conference on Applied Commodity Price Analysis, Forecasting, and Market Risk Management, Chicago, IL. Accessed Mar. 22, 2020.

        • McArthur M.
        • Reinemeyer C.
        Herding the US cattle industry toward a paradigm shift in parasite control..
        Vet. Parasitol. 2014; 204: 34-43
        • Miller J.
        Observations on nematode parasitism in cow-calf production systems in southcentral/southwestern USA..
        Vet. Parasitol. 1993; 46: 289-295
      5. Nordenson, N. 2006. Gale Encyclopedia of Medicine. Gale Group, Detroit, MI.

        • Smith G.
        • Grenfell B.T.
        • Isham V.
        • Cornell S.
        Anthelmintic resistance revisited: Under-dosing, chemoprophylactic strategies, and mating probabilities..
        Int. J. Parasitol. 1999; 29: 77-91
        • Stromberg B.
        • Averbeck G.
        The role of parasite epidemiology in the management of grazing cattle..
        Int. J. Parasitol. 1999; 29: 33-39
        • Stromberg B.E.
        • Gasbarre L.C.
        • Ballweber L.R.
        • Dargatz D.A.
        • Rodriguez J.M.
        • Kopral C.A.
        • Zarlenga D.S.
        Prevalence of internal parasites in beef cows in the United States: Results of the National Animal Health Monitoring System’s (NAHMS) beef study, 2007–2008..
        Can. J. Vet. Res. 2015; 79: 290-295
        • Vercruysse J.
        • Claerebout E.
        Treatment vs non-treatment of helminth infections in cattle: Defining the threshold..
        Vet. Parasitol. 2001; 98: 195-214
        • Volk M.J.
        • Kordas J.M.
        • Stokes R.S.
        • Ireland F.A.
        • Shike D.W.
        Effects of spring administration of extended-release eprinomectin on fescue toxicosis, performance, and reproduction of fall-born beef heifers..
        Transl. Anim. Sci. 2019; 3 (a): 20-28
        • Volk M.J.
        • Krause T.R.
        • Stokes R.S.
        • Ireland F.A.
        • Shike D.W.
        Effects of extended-release eprinomectin on fescue toxicosis, performance, and reproduction on fall-calving beef cows..
        Transl. Anim. Sci. 2019; (b): 1423-1434
        • Walker R.
        • Miller J.
        • Monlezun C.
        • LaMay D.
        • Navarre C.
        • Ensley D.
        Gastrointestinal nematode infection and performance of weaned stocker calves in response to anthelmintic control strategies..
        Vet. Parasitol. 2013; 197: 152-159
        • Waller P.
        The development of anthelmintic resistance in ruminant livestock..
        Acta Trop. 1994; 56: 233-243
        • Williams J.C.
        • Loyacano A.F.
        Internal parasites of cattle in Louisiana and other southern states..
        Louisiana State Univ. AgCenter Res. Info. Sheet. 2001; 104: 1-19