Non-chemical control methods for sheep with mixed, predominantly Teladorsagia circumcincta , nematode infections.

Abstract

Abstract Nematode infection is a potent threat to efficient and welfare-friendly livestock production. Anthelmintic treatment is a simple, cheap and effective method to control nematodes but the widespread evolution of drug resistance in parasite populations threatens the sustainability of drug treatment. Non-chemical methods to control nematodes include biological control, grazing management, nutritional supplementation, and the exploitation of genetic variation in resistance to nematode infection. Biological control includes the use of predatory fungi which can control nematode populations but the current requirement for daily feeding means that this approach will be most useful for animals that are handled daily. Grazing management schemes can reduce the intensity of infection but these schemes are not always practical. Feeding supplementary protein can control nematode infection but this may not be cost-effective on some farms. Genetic approaches include the use of resistant breeds and selective breeding. There are large differences among breeds in resistance to infection but the use of resistant breeds is not always feasible. Selective breeding is cheap and effective but requires considerable expertise. Substantial experience and knowledge will be required by farmers, consultants or veterinarians to determine the most appropriate procedures to control nematodes infection on any given farm.