Life Sciences Commons^™

Characterizing Predator-Prey Relationships Of Great Lakes Fishes Using Targeted Stomach Content Dna Analyses, Matthew Richard Charron

Electronic Theses and Dissertations

Stomach content DNA (scDNA) analyses provide important insights into feeding ecology, trophic interactions, and diet composition of predator fishes. However, previous scDNA analyses have focused on investigating a small number of predator and prey fishes using binary presence/absence data. Here, I describe the development and validation of a panel of single-species quantitative real-time PCR (qRT-PCR) assays targeting the polymorphic mitochondrial cytochrome oxidase subunit 1 (CO1) region of 28 Great Lakes prey fishes. The assay panel will significantly increase the number of targeted prey species available for predator diet assessment, while at the same time improving detection sensitivity and through-put. I …

Physiological And Behavioural Responses Of Arctic-Breeding Shorebirds To Weather And Habitat Conditions, Sara Bellefontaine

Electronic Theses and Dissertations

Arctic-breeding shorebirds balance proximate and ultimate trade-offs in an energetically demanding environment. While these species are selective of nest sites, previous research shows that the characteristics of preferred shorebird nests do not predict increased breeding success. Thus, I aimed to identify detectable mechanisms driving nest preferences in Arctic-breeding shorebirds. Using an archival dataset, I first examined long-term nest preferences in relation to wind conditions at the East Bay Migratory Bird Sanctuary, on Southampton Island, Nunavut, Canada. I then studied energetic responses of two shorebird species to weather conditions across various nest types in a field study using non-invasive heart rate …

Regulation Of Natural Killer Cell Responses By Myeloid-Derived Suppressor Cells In Mouse Mammary Tumors, Mary Ibrahim

Electronic Theses and Dissertations

Natural killer (NK) cells of the innate immune system play important roles in anti-cancer immunity. NK cell functions are regulated by inhibitory and activating receptors, which recognize specific ligands on the target cells. One example is the inhibitory NKR-P1B receptor which recognizes the ligand C-type lectin-related protein b (Clr-b). Work in our lab has shown NKR-P1B:Clr-b interactions are involved in mammary tumor immunosurveillance by NK cells. However, the cellular interactions and factors involved in modulating NK cell functions via this receptor:ligand system in the tumor microenvironment (TME) are not fully understood. This project aims to understand the role of myeloid-derived …

Exploring The Relationships Between Environmentally Influenced Foraging Behaviour, Energetics, And Breeding Decisions In Arctic Breeding Common Eiders, Erika Nissen

Electronic Theses and Dissertations

Migratory species breeding in polar environments face highly seasonal conditions and significant temporal and spatial constraints which can limit their ability to reproduce successfully. Effective energetic management is especially important at high latitudes, where a shortened breeding season and variable spring climatic conditions can restrict seasonal food availability, impact ability to initiate reproduction and successfully raise offspring. We explored this paradigm in marine benthic foraging common eiders (Somateria mollissima), at a long-term studied colonial nesting site at East Bay (Mitivik) Island, Nunavut, Canada. Eiders rely on marine prey to gain the energy necessary to invest in reproduction when arriving at …

The Role Of Cort And Anaphase Promoting Complex/Cyclosome (Apc/C) In Drosophila Sex Determination And Meiosis, Abuzar Sikander Malik

Electronic Theses and Dissertations

The E3 ubiquitin ligase, APC/C, is essential for the completion cell cycle; along with its co-activators it allows mitotic exit and maintenance of G1. APC/C marks various substrates with ubiquitin chains; marked substrates are subsequently destroyed via the 26S proteasome pathway. Cort is a Drosophila female meiosis specific activator of APC/C. Cort works within meiosis in conjunction with Fzy to mediate Securin and cyclin destruction. A C-terminal IR-tail motif and a N-terminal C-box support Cort-APC/C interaction, whereas short motifs like D-box and KEN-box on the target protein impart substrate recognition to Cort. Cort expression is tightly controlled in the female …

Examining The Effectiveness Of Probiotic Therapy For Improving Growth Performance Of Triploid Chinook Salmon (Oncorhynchus Tshawytscha) In Aquaculture Using A Behavioural Genomics Approach, Chelsea Frank

Electronic Theses and Dissertations

With an increasing human population, there has been increased production of fish to meet nutritional needs. Commercial aquaculture accounts for a significant portion of seafood production with salmonids being the major farmed finfish in Canada. To obtain greater biomass from aquaculture with minimal drawbacks (e.g., compromised flesh quality), triploidization has been implemented, altering ploidy from 2N to 3N, to induce sterility and promote energy investment towards somatic growth. Triploid individuals experience transcriptional and behavioural changes resulting in disease, mortalities, and reduced growth. Probiotic therapies (live microorganisms) have been recommended to potentially overcome drawbacks of triploidy and improve mass due to …

The Black Soldier Fly, Hermetia Illucens Linnaeus (Diptera: Stratiomyidae): A Novel Approach To Combat Food Waste In Windsor-Essex., Patricia Obianuju Okpara

Electronic Theses and Dissertations

Within Ontario alone, approximately 3.7 million tonnes of organic food waste is generated yearly. This waste includes food scraps, wasted food, and plant wastes such as leaves, plant stems, and fruit. Most of it is transported to landfills for composting each year, but the use of landfills as a method of waste management is not sustainable. It adds strain to the environment by releasing harmful greenhouse gases and by demanding landfill space. The current protocols set by the Ontario government, while promising, do not address methods that support the safe disposal of organic waste and conversion into valuable end products …

The Influence Of Administrative Timing In Triple-Negative Breast Cancer Treatments, Emily Mailloux

Electronic Theses and Dissertations

Breast cancer accounts for 25% of all cancers in Canadian women, and 15-20% of these are triple-negative breast cancers (TNBC), which have a poorer prognosis than other breast cancer subtypes. TNBC lacks expression of the estrogen receptor, progesterone receptor, and the human epidermal growth factor receptor 2 (HER2), which are common therapeutic targets in breast cancer. Due to the lack of target therapy, generalized chemotherapy treatments are used instead. The standard of care for treatment of TNBC instead consists of doxorubicin (A), cyclophosphamide (C) paclitaxel (T), and carboplatin (Carbo), that target various aspects of the cell cycle to induce cell …

Survey Of Native Predatory Hemipterans And Assessment Of Nabis Americoferus Carayon (Hemiptera: Nabidae) As A Biological Control Agent Of Lepidopteran Tomato Pests, Andrew Laflair

Electronic Theses and Dissertations

Invasive species have become a grave threat to the economic viability of our global vegetable producers. Tomato pinworm Tuta absoluta Meyrick (Lepidoptera: Gelechiidae) has expanded from its range originating from Peru to being established in nearly hundreds of countries, causing tomato production losses of up to 100% on occasion; however, it has not yet been found in Canada or the USA. Southwestern Ontario is a significant tomato producer making it a high risk from this invasive species. Efficient integrated control methods such as native biological control agents (BCAs) that avoid creating insecticide resistance are ideal. Surveys of Southwestern Ontario conservation …

Experimental Analysis Of Fish Sensory Systems: From Behavioural Responses To Physiological Extremes, Roselia Ayala-Osorio

Electronic Theses and Dissertations

Fishes are surrounded by various types of stimuli in their habitats which provide important information about their environments. Here, I investigated how various types of stimuli can affect the behaviour and physiology of two freshwater species: the invasive round goby (Neogobius melanostomus) and the black bullhead (Ameiurus melas). In chapter 2, I tested for a synergistic response in the round goby to multimodal stimuli, by presenting acoustic, visual, and olfactory stimuli separately and simultaneously. The results showed a significant decrease in the average respiration rate during multimodal stimuli suggesting that a synergistic response to multimodal stimuli …

Characterizing Hematological And Reproductive Phenotypes In The Plk4+/– Mouse, Brayden Labute

Electronic Theses and Dissertations

The polo-like kinases (Plks) are a family of serine/threonine kinases, of which there are five members. These protein kinases are involved in a multitude of processes associated with the cell cycle. These include centriole duplication, maturation of centrosomes, mitotic entry, and cytokinesis. Since the Plks are involved in such critical processes, dysregulation of these proteins are implicated in the development of a variety of malignancies. Higher and lower levels of Plk4 are both associated with tumourigenesis, therefore Plk4 can act as either an oncogene or tumour suppressor. While Plk4–/– mice are embryonic lethal, Plk4+/– mice are viable. Aged …

Studies Of Chemosensory Responses In The Pharynx Of The Sea Lamprey (Petromyzon Marinus), Hasan Huseyin Polat

Electronic Theses and Dissertations

The sea lamprey is a basal vertebrate, and the oldest extant species with taste buds. The objective of this thesis was to study the chemosensory responses from the sea lamprey’s pharynx, which is located caudal to oral cavity and medial to seven lateral brachiopores. The pharynx contains taste buds that detect and respond to tastants to inform lampreys about gustatory factors in the environment. The location of these taste buds along the lateral surface of the pharynx was first determined using scanning electron microscopy. Then using electrophysiology, our recordings from these pharyngeal regions containing taste buds picked up responses from …

The Design And Testing Of Fluorescence-Based Sensors For Phosphate And Phosphonate, Sara Hassanzadehroknabadi

Electronic Theses and Dissertations

Inorganic phosphate (Pi) is an essential compound for all living things, as it serves as a component of nucleic acids and ATP, which are required for plant growth and proliferation. However, when excess Pi enters the aquatic environment, it has severe detrimental effects through the induction of harmful algal blooms (HAB), which negatively impact aquatic life, the quality of drinking water as well as recreational activities. It is therefore critical to have fast, sensitive, and inexpensive sensors for Pi that quickly and quantitively measure its concentration in a field setting.

Phosphonates or organophosphorus compounds are phosphoric acids possessing alkyl or …

Mother Knows Best: Mechanistic Aspects Of Foraging Preference And Differential Arrestment Of Gravid Females: A Case Study On Blow Flies (Diptera: Calliphoridae), Vanessa Elizabeth Owen

Electronic Theses and Dissertations

Behavioural plasticity is a concept that describes a change in an organism’s behaviour due to their exposure to stimuli that differ from their usual environment. For instance, females of many insect species alter their behavioural responses when exposed to differing substances that they utilize for feeding, oviposition, and/or mating. Behaviours such as the frequency of walking, tasting, grooming exhibited by flies can be associated with the detection and acceptance of a suitable medium. For this thesis, the arrestment and behavioural response of gravid adult females of three species of blow flies (Diptera: Calliphoridae), Lucilia sericata Meigen, Phormia regina Meigen, and …

The Bouba/Kiki Effect On Gendered Objects In The Arabic Language, Ghadir Nassereddine

Electronic Theses and Dissertations

People are more likely to associate the nonword bouba with a round shape, and kiki with a sharp shape, an effect known as the Bouba/Kiki effect (BK) (Ramachandran & Hubbard, 2001). Relatedly, female names are associated with a round shape whereas male names are associated with a sharp shape (Sidhu & Pexman, 2015) and this effect extends to grammatically gendered nonwords in French (Sidhu, Pexman, & Saint-Aubin, 2019). These associations have not been examined in Arabic, or with real words with a grammatical gender. The present study addresses this gap by examining the influences of letter sound …

Utilizing An Integrated Approach To Explore Niche In A Complex Equatorial System, Danielle Orrell

Electronic Theses and Dissertations

Our ability to identify and understand the relationships and distributions of organisms in nature is key to exploring the rich tapestry of life seen on Earth. The term "niche" describes how animals partition resources in space and time, shaped by behavioural choices and environmental conditions. Iterations of niche over time have focused on different aspects of a species' ecological characteristics, from Grinnell’s initial study of songbird distribution (‘spatial niche’) in 1917 to Elton’s description of functional attributes shaping trophic position (‘trophic niche’). The fusion of these niche definitions formed Hutchinson’s n-dimensional niche hypervolume. The coexistence of …

The Role Of The Circadian Clock In The Intestinal Epithelium During Health, Regeneration, And Tumourigenesis, Kyle Stokes

Electronic Theses and Dissertations

The Earth’s axial rotation subjects its surface to constant periods of light and dark, this is known as photoperiod. Many organisms have adapted their physiology in accordance with this environmental constant by generating 24h rhythms in their physiological functions; these are known as circadian rhythms. Circadian rhythms are controlled by an endogenous time-keeping mechanism known as the circadian clock. Over 40% of the genome in mice and over 80% of the genome in primates has been shown to have 24h rhythms in transcription. The disruption of circadian rhythms through shiftwork, jetlag, or exposure to light at night is associated with …

The Role Of The Nkr-P1b:Clr-B Inhibitory Axis In Nk Cell-Mediated Tumour Immunosurveillance, Abd El Aziz Hendy

Electronic Theses and Dissertations

Natural killer (NK) cells are lymphocytes of the innate immune system which do not require prior priming to target infected or altered-self cells, such as tumour cells. The basic functions of NK cells include cytotoxicity and cytokine production. These cells possess numerous activating and inhibitory receptors which regulate their function based on a signalling balance. In mice, NK cells possess NKR-P1B inhibitory receptors which recognize the C-type lectin-related protein-b (Clr-b) ligand. This ligand is present on healthy self cells and may be used by cancer cells to evade NK cell effector functions. The disruption of the NKR-P1B:Clr-b axis has been …

An Integrated Approach To Understanding Anthonomus Eugenii Cano (Coleoptera: Curculionidae): An Exotic Pest Of Greenhouse And Field Pepper Crops, Diana Catalina Fernandez

Electronic Theses and Dissertations

Anthonomus eugenii, the pepper weevil is an important pest of cultivated pepper plants (Capsicum spp.). The weevil is originally from Mexico, but it is present in Central America, the Caribbean, and southern United States. Additionally, it was present and eradicated in the Netherlands, Italy, and western Canada in British Columbia. However, sporadic outbreaks occur during the pepper growing season in southern Ontario, which has prompted further investigation of its biology and management. My dissertation investigates the genetics, physiology and ecology of the pepper weevil and its implications for prevention, management, and potential establishment in southern Ontario. I investigated …

Does It Take A Community To Save A Species? Examining The Use Of Community Interactions To Restore Unionid Species At Risk, Roland Adriaan Eveleens

Electronic Theses and Dissertations

The conservation and restoration of freshwater ecosystems are complex. Knowledge from community ecology, conservation biology, and restoration ecology was integrated to interrogate the role of species interactions involving freshwater mussels (order Unionida) as keystone species. Freshwater mussels require host fish and provide ecosystem functions for other species throughout aquatic and riparian ecosystems, yet conservation efforts remain focused on focal mussel species or host fish associations. My thesis explored species co-occurrences within mussel and benthic macroinvertebrate community assemblages, and systematically reviewed the published literature to assess the breadth and reported effectiveness of mussel restoration. Community analyses confirmed species co-occurrences across environmental …

Parasites And Sexual Selection In A Sexually Dichromatic Toad, Nicole Erin Shangi

Electronic Theses and Dissertations

Parasitism is among the most common and successful life history strategies on Earth, leading to constant coevolution between parasites and hosts. Parasites continuously pressure hosts to evolve more effective parasite resistance, fueling interest in the relationships between expression of sexually selected host ornamentation and parasite resistance. By studying parasite-mediated sexual selection we gain unique insights into the evolution of animal traits. In this thesis, I attempt to further our understanding of a sexually dichromatic neotropical anuran by studying its parasites in the context of sexual selection. Firstly, in the General Introduction (Chapter 1), I reviewed important background information key to …

The Effects Of Probiotic Therapy On Stress Coping Styles Of Triploid Juvenile Farmed Chinook Salmon, Oncorhynchus Tshawytscha, Brendyn M. St. Louis

Electronic Theses and Dissertations

Triploid salmon – fish with three sets of chromosomes – are regularly used in aquaculture as they are functionally sterile and therefore avoid the decline in flesh quality associated with sexual maturation. However, triploid fish exhibit many immune, behavioural, and physiological drawbacks which reduce their condition and survival in aquaculture environments. My research examines the effects of probiotic treatment to promote behavioural and stress-related (termed ‘coping styles’) traits more suited for aquaculture environments in triploid fish with the ultimate goal of increasing fish yield. In this study, Chinook salmon (Oncorhynchus tshawytscha) crosses were developed in a 3x3 and 3x2 design, …

The Function And Evolution Of Wood-Warbler Flight Calls (Parulidae), Zach G. Gayk

Electronic Theses and Dissertations

Animals produce vocalizations to communicate with territorial rivals, to communicate with potential mates, to alert others of predators, or to stay in contact with other animals. To date, little research has focused on the vocalizations that animals use to communicate during migration. Many birds produce flight calls, which are short calls given by migratory birds on the wing. The function of flight calls is poorly understood but they are thought to help migrants maintain contact with other individuals during movements between breeding grounds and wintering grounds. Across four data chapters in my dissertation, I investigated the function and evolution of …

A Network-Based Approach For Computational Drug Repurposing On Cancer Data, Ann Reba, Thomas Alexander

Electronic Theses and Dissertations

In this thesis, we are interested in finding the best drugs that can be repurposed for the disease and able to find the adverse effects such drugs that are FDA-Approved. Developing an effective drug can be a time-consuming and expensive crucible method. Network-based machine learning methods are used for predicting a given drug for A that can be used for B. It aims at finding new indications for already existing drugs and therefore increases the available therapeutic choices at a fraction of the cost of new drug development. The perturbation gene expression data corresponding to the MCF7 cell line was …

The Effects Of Acid Rain Mitigation Efforts On The Behaviour-Dependent Movement Of Migrating Atlantic Salmon (Salmo Salar, L.) Smolts, Omar Salem Taboun

Electronic Theses and Dissertations

Acidification has led to changes in the chemistry of fresh waters and has impacted the survival of Atlantic Salmon (Salmo salar), an endangered anadromous fish species. Liming, which has been implemented to restore freshwater ecosystems, has been demonstrated to restore a suitable pH for Atlantic Salmon, however, it remained unknown to what extent liming can restore the underlying behavioural traits and migration behaviour of smolts. We captured 116 smolts from two freshwater river treatments in Nova Scotia, Canada: acidified Little River (n=17) and lime-treated West River (n=99). We performed stream-side behavioural assays and discerned five behavioural metrics: (1) …

Examining The Links Between Environmental Variation, Foraging Behaviour And Foraging Success In An Arctic Seabird, Alyssa Eby

Electronic Theses and Dissertations

Arctic regions are experiencing increasing variability in inter-annual sea ice dynamics ultimately impacting marine Arctic ecosystems. Arctic-breeding seabirds, such as thick-billed murres (Uria lomvia) are thus likely to be negatively impacted by fluctuating environmental conditions through its influence on prey availability. Additional extrinsic factors (colony size and chick demand) and intrinsic factors (sex) are also likely to impact foraging behaviour and success of murres in combination with environmental conditions. First, we tested the effect of colony size on colony sensitivity to environmental change at two low Arctic colonies of varying sizes, Coats Island, Nunavut and Digges Island, Nunavut …