TICKLESS - Reduced ticks and tick-borne diseases in sheep by integrated management

Tick-borne fever (TBF) is one of the main challenges in Norwegian sheep farming during the grazing season. TBF is caused by the bacteria Anaplasma phagocytophilum and transmitted by the tick Ixodes ricinus. Climate change, changes in land use and an increase in the deer population are factors expected to increase the population of ticks. Ticks and tick-borne pathogens are particularly widespread in the coastal areas of Norway and farmers are experiencing large losses of lambs due to TBF. The project TICKLESS focuses on identification of robust animals, natural tick enemies, integrated vector (tick) management and understanding of interactions between vegetation, climate and host animals on the tick-population and the frequency of tick-borne disease. Genetic variation in robustness is shown in many species to numerous diseases (Bishop et al., 2010). It is shown that there are marked differences between individual animals with respect to susceptibility to TBF and knowledge on within and between breed variation in robustness to tick-borne infection has potential for reducing challenges with TBF through implementing this trait into a breeding scheme. Fungal pathogens, predatory mites and ants are all thought to be important tick killers in nature and may be used in conservational biological control strategies. Knowledge on natural enemies of I. ricinus and development of biological control strategies has a great potential for reducing challenges with tick-borne diseases. The I. ricinus tick population and frequency of tick-borne pathogens interacts with climate, vegetation and host conditions and there is a need for knowledge on these interactions. Understanding the reservoir and host mechanisms of A.phagocytiophilum variants that cause TBF in sheep, as well as other tick-borne agents, is important in order to implement preventive management strategies.