Hohe perinatale Sterblichkeit in einer Schafherde im Zusammenhang mit Dreifach-Anthelminthikaresistenz

Zusammenfassung

Eine hohe Neugeborenensterblichkeit, Milchmangel und vereinzelte Todesfälle bei Mutterschafen führten zur Untersuchung einer Dorper-Schafherde in Süddeutschland. Als zugrunde liegende Ursachen wurden Abmagerung und eine hohe Belastung mit Trichostrongylus spp. trotz regelmäßiger anthelminthischer Behandlung identifiziert. Die weitere parasitologische Untersuchung der Herde mittels Eizahlreduktionstest ergab keinerlei Eizahlreduktion nach Anwendung von Ivermectin oder Albendazol sowie eine deutlich verminderte Eizahlreduktion von 57,9% nach Behandlung mit Levamisol. Diese Ergebnisse sind Zeichen einer fehlenden bzw. deutlich verringerten Wirksamkeit von Stoffen aus allen drei klassischen Anthelminthikagruppen. Dieser Fall zeigt, dass auch in Deutschland mit Mehrfachresistenzen gegen die klassischen Anthelminthikagruppen gerechnet werden muss. Einschleppung resistenter Wurmpopulationen durch Zuchttierimporte, übermäßiger Einsatz von Anthelminthika und Unterdosierung von Wirkstoffen bei Ziegen stellen mögliche Ursachen im beschriebenen Fall dar und verdeutlichen, dass dem Parasitenmanagement und der Beratung von Schaf- und Ziegenhaltern von tierärztlicher Seite erhöhtes Augenmerk zu schenken ist.

Summary

High perinatal mortality, low milk yields and occasional ewe deaths were investigated in a Dorper sheep flock in Southern Germany. Parasitic gastroenteritis due to Trichostrongylus spp. associated with severe weight loss despite regular anthelmintic treatments of the flock was identified as the underlying cause. A faecal egg count reduction (FECR) test revealed zero reduction after treatment with ivermectin or albendazole, respectively, and a FECR of 57.9% following treatment with levamisole. These results indicate a lack of, or considerably reduced efficacy of substances from all three classical groups of anthelmintics and demonstrate that triple anthelmintic resistance is also present in Germany. The introduction of resistant worm populations with imported livestock, excessive use of anthelmintic drugs and under-dosing of goats have possibly led to the problem in the flock described. Veterinary advice on anthelmintic treatments and responsible parasite control programmes are therefore crucial in small ruminant flocks.

Schlüsselwörter

Anthelminthika - Dreifachresistenz - Trichostrongylus spp. - Schafe

Key words

Anthelmintics - triple resistance - Trichostrongylus spp. - sheep

• Literatur

• 1 Anon. Part XVI Appendices. In: Diseases of Sheep. 4th edn.. Aitken ID. ed. Oxford: Blackwell; 2007: 601-603.
• 2 Artho R, Schnyder M, Kohler L, Torgerson PR, Hertzberg H. Avermectin-resistance in gastrointestinal nematodes of Boer goats and Dorper sheep in Switzerland. Vet Parasitol 2007; 144 (1–2): 68-73.
• 3 Bath GF, Malan FS, Van Wyk JA. The ‘FAMACHA^©’ ovine anaemia guide to assist with the control of haemonchosis. In: Proceedings of the 7th Annual Congress of the Livestock Health and Production Group of the South African Veterinary Association. Port Elizabeth: 5–7th June 1996: 5.
• 4 Bartley DJ, Jackson F, Sargison ND. Characterization of two triple resistant field isolates of Teladorsagia from Scottish lowland sheep farms. Vet Parasitol 2005; 123: 189-199.
• 5 Bickhardt K. Referenzwerte. In: Lehrbuch der Schafkrankheiten. Ganter M. Hrsg. Berlin: Parey; 2001: 455-458.
• 6 Borgsteede FHM, Dercksen DD, Huijbers R. Doramectin and albendazole resistance in sheep in the Netherlands. Vet Parasitol 2007; 144 (1–2): 180-183.
• 7 Chartier C, Hoste H, Bouquet W, Malpaux B, Pors I, Koch C. Periparturient rise in fecal egg counts associated with prolactin concentration increase in French Alpine dairy goats. Parasitol Res 1998; 84 (10) 806-810.
• 8 Coles GC, Giordano DJ, Tritschler JP. Efficacy of levamisole against immature and mature nematodes in goats with induced infections. Am J Vet Res 1989; 50 (07) 1074-1075.
• 9 Coles GC, Bauer C, Borgsteede FHM, Geerts S, Klei S, 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.
• 10 Coles GC, Jackson F, Pomroy WE, Prichard RK, von Samson-Himmelstjerna G, Silvestre A, Taylor MA, Vercruyesse J. The detection of anthelmintic resistance in nematodes of veterinary importance. Vet Parasitol 2006; 136: 167-185.
• 11 Escudero E, Carceles CM, Diaz MS, Sutra JF, Galtier P, Alvinerie M. Pharmacokinetics of moxidectin and doramectin in goats. Res Vet Sci 1999; 67: 177-181.
• 12 Grimshaw WTR, Hong C, Hunt KR. Potential for misinterpretation of the faecal egg count reduction test for levamisole resistance in gastrointestinal nematodes of sheep. Vet Parasitol 1996; 62: 267-273.
• 13 Kaminsky R, Babst B, Stein PA, Strehlau GA, Allan BA, Hosking BC, Rolfe PF, Sager H. Differences in efficacy of monepantel, derquantel and abamectin against multi-resistant nematodes of sheep. Parasitol Res 2010; 109 (01) 19-23.
• 14 Kaplan RM. Drug resistance in nematodes of veterinary importance: a status report. Trends Parasitol 2004; 20 (10) 477-481.
• 15 Kenyon F, Greer AW, Coles GC, Cringoli G, Papadopoulos E, Cabaret J, Berrag B, Varady M, van Wyk JA, Thomas E, Vercruysse J, Jackson F. The role of targeted selective treatments in the development of refugia-based approaches to the control of gastrointestinal nematodes of small ruminants. Vet Parasitol 2009; 164: 3-11.
• 16 Menzies P. Reproductive Health Management Programs. In: Large Animal Theriogenology. Youngquist RS, Threlfall WR. eds. St Louis: Saunders Elsevier; 2007: 701-714.
• 17 Perbix C. Die Resistenzlage von Magen-Darm-Strongyliden gegenüber Moxidectin in deutschen Schafherden. Diss med vet Tierärztliche Hochschule Hannover; 2008 http://elib.tiho-hannover.de/dissertations/perbixc_ws08.pdf
• 18 Sangster NC, Rickard JM, Hennessy DR, Steel JW, Collins GH. Disposition of oxfendazole in goats and efficacy compared with sheep. Res Vet Sci 1991; 51: 258-263.
• 19 Sargison ND, Jackson F, Bartley DJ, Moir AC. Failure of moxidectin to control benzimidazole-, levamisole- and ivermectin-resistant Teladorsagia circumcincta in a sheep flock. Vet Rec 2005; 156: 105-109.
• 20 Sargison ND, Scott PR, Wilson DJ, Macrae AI, Penny CD. Teladorsagia circumcincta resistance to moxidectin and multiple anthelmintic groups in ewes following use of the persistent drug before lambing. Vet Rec 2010; 167: 523-527.
• 21 Scheuerle MC, Mahling M, Pfister K. Anthelminthic resistance of Haemonchus contortus in small ruminants in Switzerland and Southern Germany. Wien Klin Wochenschr 2009; 121 (Suppl. 03) 46-49.
• 22 Schnyder M, Torgerson PR, Schönmann M, Kohler L, Hertzberg H. Multiple anthelmintic resistance in Haemonchus contortus isolated from South African Boer goats in Switzerland. Vet Parasitol 2005; 128 (3–4): 285-290.
• 23 Shoop WL, Haines HW, Michael BF, Eary CH. Mutual resistance to avermectins and milbemycins: oral activity of ivermectin and moxidectin against ivermectin-resistant and susceptible nematodes. Vet Rec 1993; 133: 445-447.
• 24 Van Wyk JA, Stenson MO, Van der Merwe JS, Vorster RJ, Viljoen PG. Anthelmintic resistance in South Africa: surveys indicate an extremely serious situation in sheep and goat farming. Onderstepoort J Vet Res 1999; 66 (04) 273-284.
• 25 Waller PJ. Anthelmintic resistance. Vet Parasitol 1997; 72: 391-412.