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Gastrointestinal nematode parasites are the single most important health problem of sheep and goats. Traditionally, parasites have been controlled by frequent administration of anthelmintic drugs. However, the emergence of multiple-drug-resistant parasites now threatens this paradigm of control and new approaches are required. Anthelmintics can no longer be thought of as a convenient and inexpensive management tool for maximizing animal productivity. Instead, anthelmintics must be thought of as extremely valuable and limited resources that should be used prudently. In response to this changing paradigm of anthelmintic use, new recommendations for parasite control now exist. A key tenet of this approach, referred to as "Smart Drenching", is to use the best available knowledge to develop strategies that maximize the effectiveness of treatments while also decreasing the development of drug resistance. Additionally, new innovative schemes using novel and sustainable approaches must be implemented. An overall strategy that integrates these approaches is referred to as "sustainable integrated parasite management" (sIPM). However, by its very nature sIPM is much more complicated and difficult to implement than casual administration of anthelmintics. Consequently, successful implementation of sIPM will only be possible with the help and active involvement of veterinarians and other animal health professionals. Because multiple-drug resistance in parasites is now the status quo, and development of further drug resistance is almost certain to outpace the development of new anthelmintics, it is critical that this new philosophy and approach to parasite control be embraced and implemented immediately., The Bovine Practitioner, Vol. 47, No. 2 (2013 Summer)

Anthelmintic resistance is an increasing challenge in the control of parasites in livestock.The fecal egg count reduction test (FECRT) is the practical gold standard method forevaluating resistance, but the interpretation is complicated due to high levels ofvariability. Several factors contribute to cause this high variability and these must betaken into account to accurately identify a reduction in anthelmintic efficacy. To addressthis problem, we developed a hierarchical statistical model for analysis of FECRT datafrom multiple farms. The model includes animal effect and farm clusters as randomeffects. Resistance classifications are based on model adjusted lower confidence limit(LCL) values of predicted mean efficacies on each farm. The model was used to evaluatethe efficacy of pyrantel embonate paste from 64 Danish horse farms. On these farms 614out of 1644 horses had egg counts = 200 eggs per gram (EPG) and were treated. Posttreatment samples and information on age, gender and farm zip code were collected foreach horse. In addition, individual coprocultureswere performed on all pretreatment fecalsamples to determine the presence of Strongylus vulgaris, with 31farms (48.4 %) testingpositive. The efficacy of pyrantel was unaffected by the presence of S. vulgaris on thefarm. The cutoff LCL values used for classifying farms as pyrantel resistant were: >92%:no resistance, 88-92%: suspect resistance, and LCLs, we classified 7 (10.93 %) farms as pyrantel resistant, 5 (7.81 %) as suspectresistant and the remainder of farms (81.25%) as not resistant. In comparison withunadjusted LCLs, the model provided a more stable classification of farms with a 1.1 %12false discovery rate. The statistical model presented here can be adapted to handleFECRT data obtained from other livestock species, drug types, and parasite species.

Gastrointestinal nematode (GIN) parasites are the single most important health problem of sheep and goats. Traditionally, parasites have been controlled by frequent administration of anthelmintic drugs. However, the emergence of multiple-drug resistant parasites now threatens this paradigm of control and new approaches are required. Anthelmintics can no longer be thought of as an inexpensive management tool to be used as needed to maximize animal productivity. Instead anthelmintics must be thought of as extremely valuable and limited resources that should be used prudently. In response to this changing paradigm of anthelmintic use, new recommendations for parasite control have been proposed. The basis of this approach is to use the knowledge we have about the parasite, the animal, and the drugs to develop strategies that maximize the effectiveness of treatments while also decreasing the development of drug resistance. The term "Smart Drenching'' is often used to describe this approach to worm control. Due to the complexities ofinstituting such a program, successful implementation will only be possible with the help and active involvement of small ruminant veterinarians and other animal health professionals. Additionally, new innovative schemes using novel and sustainable approaches must be implemented. There are a number of new non-chemical technologies that will become increasingly important in GIN control programs both in the short and long term future. However, it is highly likely that any new technologies or developments in non-chemical GIN control methods will be less effective than chemical control has been (prior to emergence of drug resistant parasites). Therefore, as novel non-chemical control modalities become available and widely applied, anthelmintics will still be required for life-saving therapy when control fails. Unless veterinarians take an active and leading role in the education of small ruminant owners and help to implement these new approaches to parasite control, there may be no effective anthelmintics remaining when that time comes., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2006