Comparative Tick Gene Expression in Brahman and Holstein-Friesian Cattle

Summary

This project funded a small trial to provide tick and animal samples to complement milestones within the larger tick vaccine project funded by the Beef CRC and the Qld Smart State Innovation Fund (2005-2010). The main aim of this study was to compare the gene expression of ticks raised on resistant cattle (Brahman) with ticks raised on susceptible cattle (Holstein-Friesian). Tick gene expression profiles from ticks collected from resistant cattle revealed over 200 genes not expressed by ticks raised on susceptible cattle. These genes are under further investigation as putative vaccine candidates. A secondary aim of this trial was to collect and study skin samples from naïve and infested Brahman and Holstein-Friesian cattle to add to gene expression data collected previously. In addition, skin biopsy samples taken from cattle before and after infestation were examined using immuno-histochemistry to determine the differences in the skin immune responses at the tick:host interface. Understanding the behaviour and physiology of ticks on resistant breeds, and the bovine skin responses leading to strong immunity of resistant breeds will contribute to the development of a new tick vaccine.​​​​​​