Towards the development of a chemical lure to improve the management of invading rat populations

Introduced species, such as Rattus norvegicus and Rattus rattus,have contributed to the extinction of many native animals and plants in New Zealand(NZ). Current strategies exist to monitor, manage and eradicate pest species. However, these haven’t always been completely successful and tools to detect small or invading densities remain to be developed. One possible new method to address this problem is the application of chemical attractants (lures). Recently, a major urinary protein (MUP) has been shown in male miceto act as a sexual attractant. MUPs modulate the release of volatile attractants and have potential to act as attractants themselves. Our aim was to determine if a similar MUP(s) and associated volatiles are present in the urine of rats, with the prospect of creating a chemical lure to use in rat detection and eradication. Using Gas Chromatography/Mass Spectrometry, potential volatiles in rat urine have been identified. Analysis of rat urine by gel electrophoresis has shown MUPs present in both sexes. A 22.4 kDa MUP in Rattus norvegicushas been synthesised and expressed in E.coliusing recombinant DNA technology. Preliminary steps have been made towards the production of a MUP based on ship rat DNA sequence. Future behavioral trials are needed to investigate whether the synthesised protein, in the presence or absence of the urinary-derived volatiles, is a sexual attractant.