Managing anthelmintic resistance: Untreated adult ewes as a source of unselected parasites, and their role in reducing parasite populations

References

• Brunsdon , RV . 1964 . The seasonal variations in the nematode egg counts of sheep: a comparison of the spring rise phenomenon in breeding and unmated ewes. . New Zealand Veterinary Journal , 12 : 75 – 80 .
   PubMedGoogle Scholar
• Brunsdon , RV . 1967 . The significance of Nematodirus in New Zealand . New Zealand Veterinary Journal , 15 : 105 – 108 .
   PubMedGoogle Scholar
• Brunsdon , RV . 1970 . The spring-rise phenomenon: seasonal changes in the worm burdens of breeding ewes and in the availability of pasture infection . New Zealand Veterinary Journal , 18 : 47 – 54 .
   PubMedGoogle Scholar
• Brunsdon , RV . 1980 . Principles of helminth control . Veterinary Parasitology , 6 : 185 – 215 .
   Web of Science ®Google Scholar
• Charleston , WAG . 1986 . “ Parasites ” . In Sheep Production. Vol. 2. Feeding, Growth and Health Edited by: SN, , McCutcheon , MF, , McDonald and GA , Wickham . 204 – 243 . Auckland, , NZ : New Zealand Institute of Agricultural Science and Ray Richards Publisher, . In
   Google Scholar
• Familton , AS . 1991 . Re-examination of gastrointestinal parasite control — the contribution of the ewe . Proceedings of the 21st Annual Seminar of the Society of Sheep and Beef Cattle Veterinarians of the New Zealand Veterinary Association , : 25 – 35 .
   Google Scholar
• Familton , AS , McAnulty , RW , Thompson , KF and Sedcole , JR . 1995 . The effect of anthelmintic treatment of ewes during pregnancy . Proceedings of the New Zealand Society of Animal Production , 55 : 211 – 213 .
   Google Scholar
• Leathwick , DM , Barlow , ND and Vlassoff , A . 1992 . A model for nematodiasis in New Zealand lambs . International Journal for Parasitology , 22 : 789 – 799 .
   PubMed Web of Science ®Google Scholar
• Leathwick , DM , Vlassoff , A and Barlow , ND . 1995 . A model for nematodiasis in New Zealand lambs: The influence of drenching and grazing management on the development of anthelmintic resistance . International Journal for Parasitology , 25 : 1479 – 1491 .
   PubMed Web of Science ®Google Scholar
• Leathwick , DM , Miller , CM , Atkinson , DS , Haack , NA , Alexander , R , Oliver , A-M , Waghorn , TS and Sutherland , IA . 2006 a . Drenching adult ewes: Implications of anthelmintic treatments pre- and post-lambing on the development of anthelmintic resistance . New Zealand Veterinary Journal , 54 : 297 – 304 .
   PubMed Web of Science ®Google Scholar
• Leathwick , DM , Waghorn , TS , Miller , CM , Atkinson , DS , Haack , NA and Oliver , A-M . 2006 b . Selective and on-demand drenching of lambs: Impact on parasite populations and performance of lambs . New Zealand Veterinary Journal , 54 : 305 – 312 .
   PubMed Web of Science ®Google Scholar
• Marley , CL , Fraser , MD , Davies , DA , Rees , ME , Vale , JE and Forbes , AB . 2006 . The effect of mixed or sequential grazing of cattle and sheep on the faecal egg counts and growth rates of weaned lambs when treated with anthelmintics . Veterinary Parasitology , 142 : 134 – 141 .
   PubMed Web of Science ®Google Scholar
• Martin , PJ . 1987 . Development and control of resistance to anthelmintics . International Journal for Parasitology , 17 : 493 – 501 .
   PubMed Web of Science ®Google Scholar
• McKenna , PB . 1981 . The diagnostic value and interpretation of faecal egg counts in sheep . New Zealand Veterinary Journal , 29 : 129 – 132 .
   PubMed Web of Science ®Google Scholar
• Michel , JF . 1985 . Strategies for the use of anthelmintics in livestock and their implications for the development of drug resistance . Parasitology , 90 : 621 – 628 .
   PubMed Web of Science ®Google Scholar
• Soulsby , EJL . 1968 . “ Nematodes ” . In Helminths, Arthropods and Protozoa of Domesticated Animals , 6th Edtn , 142 – 330 . London, , UK : Baillière, Tindall and Cassell .
   Google Scholar
• Stafford , KJ , West , DM and Pomroy , WE . 1994 . Nematode worm egg output by ewes . New Zealand Veterinary Journal , 42 : 30 – 32 .
   PubMed Web of Science ®Google Scholar
• Van Wyk , JA . 2001 . Refugia — overlooked as perhaps the most potent factor concerning the development of anthelmintic resistance . Onderstepoort Journal of Veterinary Research , 68 : 55 – 67 .
   PubMed Web of Science ®Google Scholar
• Waghorn , TS , Leathwick , DM , Rhodes , AP , Lawrence , KE , Jackson , R , Pomroy , WE , West , DM and Moffat , JR . 2006 a . Prevalence of anthelmintic resistance on sheep farms in New Zealand . New Zealand Veterinary Journal , 54 : 271 – 277 .
   PubMed Web of Science ®Google Scholar
• Waghorn , TS , Leathwick , DM , Rhodes , AP , Jackson , R , Pomroy , WE , West , DM and Moffat , JR . 2006 b . Prevalence of anthelmintic resistance on 62 beef cattle farms in the North Island of New Zealand . New Zealand Veterinary Journal , 54 : 278 – 282 .
   PubMed Web of Science ®Google Scholar