First report of anthelmintic resistance in Haemonchus contortus in alpacas in Australia

Particle and Fibre Toxicology

Robin B Gasser¹  Jennifer A Charles¹  Angus JD Campbell¹  Abdul Jabbar¹ 

[1] Faculty of Veterinary Science, The University of Melbourne, Werribee, VIC 3030, Australia

关键词: Haemonchus contortus;    Gastrointestinal nematodes;    Macrocyclic lactones;    Alpaca;    Anthelmintic resistance;   

Others  :  824827
DOI  :  10.1186/1756-3305-6-243

 received in 2013-07-16, accepted in 2013-08-17,  发布年份 2013

【 摘 要 】

Background

Parasitic nematodes can cause substantial clinical and subclinical problems in alpacas and anthelmintics are regularly used to control parasitic nematodes in alpacas. Although anthelmintic resistance has been reported in ruminants worldwide, very little is known about anthelmintic resistance in alpacas. The present study was carried out to confirm a suspected case of anthelmintic resistance in Haemonchus contortus in alpacas in Australia.

Methods

Post mortem examination of an alpaca was conducted to determine the cause of its death. To confirm a suspected case of macrocyclic lactone (ML) resistance in H. contortus in alpacas, a faecal egg count reduction test (FECRT) was performed using closantel (7.5 mg/kg) and ivermectin (0.2 mg/kg). Nematode species were identified by morphological and molecular methods.

Results

Post mortem examination of a 1-year-old female alpaca that had died following a brief period of lethargy, anorexia and recumbency revealed severe anaemia, hypoproteinaemia and gastric parasitism by adult Haemonchus contortus, despite recent abamectin (0.2 mg/kg) treatment. Based on these findings and the exclusive use of MLs in the herd over the preceding six years, ML resistance in parasitic nematodes of alpacas on this farm was suspected. FECRT revealed that the efficacy of closantel was 99% (95% CI 93-100), whereas that of ivermectin was 35% (95% CI 0-78), indicating that the treatment failure was likely due to the presence of ML-resistant nematodes. Larval culture of faecal samples collected following ivermectin treatment consisted of 99% H. contortus and 1% Cooperia oncophora, a result confirmed using a PCR assay.

Conclusions

This study provides the first evidence of ML resistance in H. contortus in alpacas in Australia. Based on the extent of anthelmintic resistance in sheep gastrointestinal nematodes in Australia, veterinarians and alpaca owners should be encouraged to implement integrated parasite management strategies to improve nematode control in alpacas.

【 授权许可】

   
2013 Jabbar et al.; licensee BioMed Central Ltd.

【 图 表 】

Figure 1.

【 参考文献 】

• [1]Gerken M, Renieri C: South American camelids research. Göttingen, Germany, Proc. 4th European Symp Volume 1 2004, 7-9. [South American Camelids and DECAMA European Seminar] p. 7-8
• [2]Foster M: Emerging Animal and Plant Industries-Their Value to Australia. 2nd edition. Canberra, Australia: Rural Industries Research and Development Corporation, Union Offset Printing; 2009:5-7.
• [3]Leguia G: The epidemiology and economic impact of llama parasites. Parasitol Today 1991, 7:54-56.
• [4]Windsor RS, Windsor RHS, Teran M: Economic benefits of controlling internal and external parasites in South American camelids. Ann N Y Acad Sci 1992, 16:398-405.
• [5]Hill FI, Death AF, Wyeth TK: Nematode burdens of alpacas sharing grazing with sheep in New Zealand. N Z Vet J 1993, 41:205-208.
• [6]Beldomenico PM, Uhart M, Bono MF, Marul C, Baldi R, Peralta JL: Internal parasites of free-ranging guanacos from Patagonia. Vet Parasitol 2003, 118:71-77.
• [7]Windsor RHS, Teran M, Windsor RS: Effects of parasitic infestation on the productivity of alpacas (Lama pacos). Trop Anim Health Prod 1992, 24:57-62.
• [8]Gillespie R-AM, Williamson LH, Terrill TH, Kaplan RM: Efficacy of anthelmintics on South American camelid (llama and alpaca) farms in Georgia. Vet Parasitol 2010, 172:168-171.
• [9]Sarre C, Claerebout E, Vercruysse J, Levecke B, Geldhof P, Pardon B, Alvinerie M, Sutra JF, Geurden T: Doramectin resistance in Haemonchus contortus on an alpaca farm in Belgium. Vet Parasitol 2012, 185:346-351.
• [10]Wood IB, Amaral NK, Bairden K, Duncan JL, Kassai T, Malone JB Jr, Pankavic JA, Reinecke RK, Slocombe O, Taylor SM, Vercruysse J: World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) second edition of guidelines for evaluating the efficacy of anthelmintics in ruminants (bovine, ovine, caprine). Vet Parasitol 1995, 58:181-213.
• [11]Whitlock HV: Some modifications of the McMaster helminth egg counting technique and apparatus. J Counc Sci Ind Res (Aust) 1948, 21:177-180.
• [12]Coles G, Bauer C, Borgsteede FHM, Klei TR, Taylor MA, Waller PJ: World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) methods for the detection of anthelmintic resistance in nematodes of veterinary importance. Vet Parasitol 1992, 44:35-44.
• [13]MAFF: Manual of Veterinary Parasitological Laboratory Techniques. London, UK: Her Majesty’s Stationery Office; 1986:20-27.
• [14]Bott NJ, Campbell BE, Beveridge I, Chilton NB, Rees D, Hunt PW, Gasser RB: A combined microscopic-molecular method for the diagnosis of strongylid infections in sheep. Int J Parasitol 2009, 39:1277-1287.
• [15]Besier RB, Love SCJ: Anthelmintic resistance in sheep nematodes in Australia: the need for new approaches. Aust J Exp Agric 2003, 43:1383-1391.
• [16]Larsen JWA, Anderson N, Ware JW, de Fegely C: The productivity of Merino flocks in South-Eastern Australia in the presence of anthelmintic resistance. Small Ruminant Res 2006, 62:87-93.
• [17]Kaplan RM, Vidyashankar AN: An inconvenient truth: global worming and anthelmintic resistance. Vet Parasitol 2012, 186:70-78.
• [18]Jabbar A, Iqbal Z, Kerboeuf D, Muhammad G, Khan MN, Afaq M: Anthelmintic resistance: the state of play revisited. Life Sci 2006, 79:2413-2431.
• [19]Bailey JN, Kahn LP, Walkden-Brown SW: Availability of gastro-intestinal nematode larvae to sheep following winter contamination of pasture with six nematode species on the Northern Tablelands of New South Wales. Vet Parasitol 2009, 160:89-99.
• [20]Martin PJ, Le Jambre LF, Claxton JH: The impact of refugia on the development of thiabendazole resistance in Haemonchus contortus. Int J Parasitol 1981, 11:35-41.
• [21]Gonzalez-Canga A, Belmar-Liberato R, Escribano M: Extra-label use of ivermectin in some minor ruminant species: pharmacokinetic aspects. Curr Pharm Biotechnol 2012, 13:924-935.
• [22]Jarvinen JA, Miller JA, Oehler DD: Pharmacokinetics of ivermectin in llamas. Vet Rec 2002, 150:344-346.
• [23]Dadak AM, Asanger H, Tichy A, Franz S: Establishing an efficacious dose rate of monepantel for treating gastrointestinal nematodes in llamas under field conditions. Vet Rec 2013, 172:155-156.
• [24]Varady M, Praslička J, Čorba J: Multiple anthelmintic resistance of nematodes in imported goats. Vet Rec 1993, 132:387-388.
• [25]Schnyder M, Torgerson PR, Schonmann M, Kohler L, Herzberg H: Multiple anthelmintic resistance in Haemonchus contortus isolated from South African Boer goats in Switzerland. Vet Parasitol 2005, 128:285-290.
• [26]Bishop JK, Rickard LG: Faecal survey of llamas (Lama glama) in Oregon: incidental recovery of Nematodirus battus. J Am Vet Med Assoc 1987, 191:1579-1581.
• [27]Rickard LG: Update on llama medicine. Parasites. Vet Clin North Am Food Anim Pract 1994, 10:239-247.
• [28]Fowler ME: Medicine and Surgery of South American Camelids. 3rd edition. Iowa: USA, Blackwell Publishing; 2010:1-15.
• [29]Karlsson LJE, Greeff JC: Genetic aspects of sheep parasitic diseases. Vet Parasitol 2010, 189:104-112.
• [30]van Wyk JA, Bath GF: The FAMACHA© system for managing haemonchosis in sheep and goats by clinically identifying individual animals for treatment. Vet Res 2002, 33:509-529.
• [31]Rendell DK: Anthelmintic resistance in cattle nematodes on 13 south-west Victorian properties. Aust Vet J 2010, 88:504-509.