ESSENTIAL LEAF OILS OF JUNIPERUS COMMUNIS AS A REPELLENT OR ATTRACTANT OF ORNITHODOROS TARTAKOVSKYI By Chelsea J. Hughes Soft ticks are vectors of multiple infectious agents, and some of these infectious agents can cause disease in humans and livestock. Therefore, there is a need for a repellent that will prevent soft ticks from feeding on these organisms and transmitting these infectious agents. I placed unfed nymphs in the center of a four-way arena to provide choices among carbon dioxide, J. communis essential leaf oil, J. communis essential leaf oil and carbon dioxide, and a control blank vial to examine the potential of Juniperus communis essential leaf oil as a repellent against the soft tick Ornithodoros tartakovskyi. I used a secondary attachment assay to determine if J. communis essential leaf oil prevented O. tartakovskyi from attaching to a membrane and feeding because a substance may prevent tick-host attachment but not be a repellent. Both assays indicated that J. communis essential leaf oil does not repel O. tartakovskyi but suggested attraction. Based on these results, I tested if J. communis essential leaf oil would attract O. tartakovskyi using a two-way olfactometer. After these trials, it appears that J. communis essential leaf oil does not influence the behavior of O. tartakovskyi, despite the findings of previous studies that demonstrate that such oils repel other species of ticks. The data also suggest that O. tartakovskyi may not behave naturally in a two-way olfactometer when given the choice between a blank control and carbon dioxide because the nymphs were not attracted to carbon dioxide, despite the reliance of ticks on this gas for finding hosts. This study has important implications for finding appropriate natural repellents. ACKNOWLEDGEMENTS I would like to thank Greg Adler, Rob Mitchell, and Steve Bentivenga for serving as advisors on my thesis committee. Without your guidance and support, this project would never have come to fruition. I would also like to thank Greg Potratz and Tom Perzentka for providing me with supplies as well as helping me assemble various components of the olfactometers. Lastly, special thanks to Steve Schaar for his input and the Michalski lab for allowing me to borrow their equipment. I am extremely grateful for the aid of all mentioned contributors. ii i TABLE OF CONTENTS Page LIST OF TABLES .............................................................................................................. 2 LIST OF FIGURES ............................................................................................................ 3 CHAPTER I - INTRODUCTION ...................................................................................... 4 CHAPTER II - EXPERIMENTAL DESIGN ................................................................... 22 CHAPTER III - CONCLUSION ...................................................................................... 32 REFERENCES ................................................................................................................. 35 iv LIST OF TABLES Table 1. Review of tick-borne diseases Table 2. The effect of J. communis essential leaf oil on O. tartakovskyi in a four- way arena Table 3. The effect of J. communis essential leaf oil on O. tartakovskyi nymph feeding Table 4. The effect of J. communis essential leaf oil on O. tartakovskyi in a two- way olfactometer Table 5. The effect of J. communis essential leaf oil and carbon dioxide on O. tartakovskyi in a two-way olfactometer Table 6. The effect of carbon dioxide on O. tartakovskyi in a two-way olfactometer under two ambient light conditions v LIST OF FIGURES Figure 1. Arena setup Figure 2. Two-way olfactometer setup vi 1 Chapter 1 Introduction A Review of Tick-borne Diseases Humans have expanded beyond their ancestral homeland in the Rift Valley of East Africa and now occupy virtually all terrestrial habitats on earth (Maslin, 2014). In doing so, they have unwittingly entered the transmission cycles of an array of infectious agents, many of which cause diseases in not only humans but also domesticated animals. The transmission cycles of many agents require blood-feeding arthropods as vectors, including flies, heteropterans, fleas, and especially ticks (Leitner et al., 2015),(Klotz et al., 2010). A large number of infectious agents are transmitted by the 899 known tick species (Dantas-Torres et al., 2012), including both hard (Ixodidae) and soft (Argasidae) ticks (Table 1). Table 1. Review of tick-borne diseases Species Pathogen vectored Hosts References Soft ticks Argas Borrelia anserina, Pretoria Birds Labuda & Nuttall (2008), africolumbae virus Gothe et al. (1981) Argas arboreus Francisella [Wolbachia] Cattle, birds Belozerov persica et al. (2003), Hoogstraal (1985), Mumcuoglu et al. (2005), Noda et al. (1997), Larson et al. (2016) Argas cooleyi Mono Lake virus, Sixgun virus, Humans Hoogstraal (1985), Sapphire II virus, Sunday Calisher et al. (1988), Canyon Vermeil et al. (1996), virus Labuda & Nuttall (2008), 2 de la Fuente et al. (2008) Argas hermanni Chenuda virus, Abu Hammad Unknown Hoogstraal (1985), Labuda virus, Royal Farm virus, West & Nuttall (2008) Nile virus, Grand Arbaud virus, Nyamanini virus, Quaranfil virus Argas Mono Lake virus Humans Schwan et al. (1992), monolakensis Vermeil et al. (1996), de la Fuente et al. (2008) Argas persicus Aegyptianella pullorum, Poultry, other Keirans Borrelia anserina, Rahnella birds et al. (2001), aquatilis, Pseudomonas Ntiamoa-Baidu et al. fluorescens, Enterobacter (2004), Ghosh et al. cloacae, Chryseomonas (2007), Petney luteola, Chryseobacterium et al. (2004), Gothe et al. meningosepticum (1981), Montasser (2005) Argas pusillus Issyk-Kul fever virus Bats, humans Labuda & Nuttall (2008), Tahmasebi et al. (2010), de la Fuente et al. (2008) Argas reflexus Aegyptianella pullorum, Domestic Hoogstraal (1985), Uukuniemi virus, poultry Gavrilovskaya (2001), de CCHF virus la Fuente et al. (2008) Argas Issyk-Kul Fever virus, Sokuluk Bats Hubbard vespertilionis virus, Borrelia burgdorferi et al. (1998), Hoogstraal (1985), Gavrilovskaya (2001), de la Fuente et al. (2008) Carios amblus Mono Lake virus Humans Labuda & Nuttall (2008), Fuente et al. (2008) Carios capensis Hughes virus, Soldado virus, Seabirds, Converse et al. (1975), Quaranfil virus, Saumarez reef humans Hoogstraal (1985), Labuda virus, Upolu virus, Nyaminini & virus Nuttall (2004, 2008) Carios kelleyi Borrelia johnsoni, Two Unknown Schwan et al. (2009), 3 undescribed Rickettsia spp., Loftis et al. (2005), Rickettsia felis, Borrelia Reeves lonestari et al. (2006) Carios Chenuda virus, West Nile virus Unknown Labuda & Nuttall maritimus (2008) Ornithodoros Huacho virus, Unknown Hoogstraal (1985) amblus Punta Salinas virus Ornithodoros Borrelia caucasica, Borrelia Humans, Assous & Wilamowski asperus microti, Borrelia baltazardi rodents (2009), Parola & Raoult (2001) Ornithodoros Baku virus Pigeons Hoogstraal et al. (1979) coniceps Ornithodoros African swine fever virus, Pigs Groocock et al. (1980), coriaceus Bluetongue virus Stott et al. (1985), Kleiboeker et al. (1998), Labuda & Nuttall (2004) Ornithodoros Hughes virus, Soldado virus, Humans Labuda & Nuttall (2004), denmarki Raza virus, Quaranfil group de la Fuente et al. (2008) Ornithodoros Qalyub virus (QYB), African Humans, pigs Miller et al. (1985), erraticus swine fever virus, Borrelia Labuda & Nuttall (2004, microti, Borrelia hispanica, 2008), Basto et al. (2006) Borrelia crocidurae, Babesia meri Ornithodoros Borrellia graingeri Humans Parola & Raoult graingeri (2001) Ornithodoros Borrelia hermsi Humans Dana (2009), Schwan et hermsi al. (2007) Ornithodoros Matucare virus Unknown Labuda & Nuttall kohlsi (2008) Ornithodoros Colorado tick fever group Humans Sonenshine et al. (2002) lagophilus Ornithodoros CCHF virus Cattle Moemenbellah- Fard et al. 4 lahorensis (2009), Ahmed et al. (2007), Ghosh et al. (2007), Hoogstraal (1985), Telmadarraiy et al. (2010) Ornithodoros Soldado virus Seabirds Labuda & Nuttall (2004), maritimus de la Fuente et al. (2008) Ornithodoros African swine fever virus, Humans, pigs Cutler (2006), Lawrie et moubata West Nile virus, al. (2004), Shepherd et al. HIV, (1989), Durden et al. Hepatitis B virus, Borrelia (1993), duttoni Humphery-Smith et al. (1993), Jupp et al. (1987), Haresnape & Wilkinson (1989), Labuda & Nuttall (2004, 2008) Ornithodoros African swine fever virus, Humans Kleiboeker & Scoles parkeri Karshi and Langat virus, (2001), Turell et al. (1994, Borrelia parkeri 2004), Dana (2009), Dworkin et al. (2002) Ornithodoros African swine fever virus, Humans, pigs Haresnape & Wilkinson porcinus Borrelia duttoni (1989), Labuda & Nuttall (2004, 2008), Lawrie et al. (2004), Shepherd et al. (1989), Durden et al. (1993), Humphery-Smith et al. (1993), Jupp et al. (1987) Ornithodoros African swine fever virus Reptiles Nava et al. (2007), Venzal puertoricensis et al. (2006, 2008), Bermúdez et al. (2010), Endris et al. (1989) Ornithodoros Borrelia venezuelensis Humans Parola & Raoult (2001) rudis Ornithodoros African swine fever virus, AHF Camel, Ghosh et al. (2007), Gaber savignyi virus, Bluetongue virus, sheep, goats, et al. (1984), Helmy Borrelia crocidurae cows, buffalo (2000), Shanbaky & Helmy (2000) 5 Ornithodoros African swine fever virus, Pigs Vial et al. (2006), Turell et sonrai Karshi and Langat virus, al. (1994, 2004), Vial et al. Bandia virus, Borrelia (2007), Labuda & Nuttall crocidurae, Coxiella burnetii (2008) Ornithodoros Borrelia mazzottii Rodents, Parola & Raoult (2001)