Sustainable management of pasture parasites in Norwegian beef and dairy cattle

Use of pasture is important for cattle production throughout Norway. Grazing cattle can, however, be infected by parasites that affect their production negatively. The pasture parasites (PP) may also cause clinical disease, even mortality, and thus adversely affect animal health and welfare. The main objective of this project is to contribute to a sustainable cattle production through increased knowledge of the occurrence and importance of PPs and better tests for the detection of these parasites. This also includes studies of resistance to drugs commonly used to control parasites, anthelmintic resistance (AR). The main focus will be on the parasites Ostertagia ostertagi in the gastrointestinal system and Fasciola hepatica that infects the liver. A survey asking Norwegian cattle farmers about their perception of the importance of PPs and currently used control strategies is completed. A similar survey is distributed to veterinarians in production animal Practice. This study will be followed by qualitative interviews. The results will be used as a basis for further work in the project and improvement of control strategies on cattle farm. The project will establish, optimize and evaluate diagnostic tests, including molecular methods, for the detection and quantification of important PPs. The use of tests measuring antibody levels to important parasites in bulk tank milk and recordings of liver fluke in the abattoirs, will provide tools to target herds in need of better parasite management. Furthermore, the impact of O. ostertagi and F. hepatica on production efficiency will be investigated by combining results of diagnostic tests with data from the Norwegian Dairy Herd Recording System and the Norwegian Beef Herd Recording System. The aim of the project is to provide the Norwegian cattle industry with increased knowledge about the significance of PPs and AR and new tools for detection and quantification. The knowledge gained will make the basis for updated recommendations on parasite control in Norwegian beef and dairy herds. The collaboration between researchers at NMBU, international researchers and the cattle industry, represented by TINE and Animalia, ensures the relevance of the project and the implementation of the findings in the industry.

Grazing cattle are infected by parasites that influence their health and production. The main focus of the project will be on the gastrointestinal nematode Ostertagia ostertagi and the liver fluke Fasciola hepatica. These parasites may cause clinical disease, but not least production loss due to subclinical, chronic infections. The primary aim of the project is to contribute to a sustainable cattle production in Norway through increased knowledge of the significance of pasture parasites (PP) and improved diagnostic tests. Cattle farmers and veterinarians´ perception of impact of PP and their current management strategies will be investigated. Diagnostic tests, including molecular methods, for detection and quantification of important PP will be established, optimized and evaluated. The performance of tests measuring antibody levels to O.ostertagi and F.hepatica in bulk tank milk and recordings of liver fluke in the abattoirs will also be evaluated to provide tools to target herds in need of better parasite management. The impact of O. ostertagi and F. hepatica on production efficiency will be investigated by combining results of evaluated diagnostic tests with production data from the Norwegian Dairy Herd Recording System and the Norwegian Beef Herd Recording System. Finally, the project will establish a molecular method for detection of anthelmintic resistance (AR) and investigate the occurrence of AR in Norwegian cattle. The project will provide the cattle industry with increased knowledge about the significance of PP and anthelmintic resistance and furthermore new tools for detection and quantification of important PP. The knowledge gained will make the basis for updated recommendations on parasite control in Norwegian beef and dairy herds. The collaboration between researchers at NMBU, international researchers and the cattle industry, represented by TINE and Animalia, ensures the relevance of the project and the implementation of the findings in the industry.