Genetic Resistance of Bovines to Theileriosis

SIMPLE SUMMARY: Theileriosis is a potentially fatal disease for susceptible cattle and is an important cause of economic losses for farms around the world. Nevertheless, there are animals that can be protected with vaccination or acaricides, or that can recover after treatment is carried out. However, the current trend is to try to reduce the use of drugs and to implement more sustainable strategies. The following review presents the parasite’s life cycle, the clinical signs and lesions resulting from infection by Theileria spp. and discusses current strategies to control the disease and the development of strategies based on the genetic selection of resistant animals. ABSTRACT: Diseases caused by ticks have a high impact on the health, welfare, and productivity of livestock species. They are also an important cause of economic losses in farms worldwide. An example of such diseases is theileriosis, which can be controlled by drugs or vaccines, although these are not fully efficient. Therefore, there is a need to develop alternative and more sustainable and efficient complementary strategies. These may involve the identification and selection of animals more resistant to the disease. Several previous studies have identified significant differences in resistance between different breeds, with resistant breeds typically identified as those native to the region where they are being studied, and susceptible as those from exotic breeds. These studies have indicated that resistance traits are intrinsically related to the modulation of the immune response to infection. This review aims to systematize the general knowledge about theileriosis, emphasize resistance to this disease as a sustainable control strategy, and identify which traits of resistance to the disease are already known in cattle.