Biological Sciences

Supervisory Team : Dr Natasha Kruger (Lecturer in Animal Ecology), Prof Iza Radecka (Professor in Biotechnology)

About the Project:

Background

Amphibians represent the most threatened vertebrate group, with 41% of species being in danger of extinction (IUCN, 2023). The common toad (Bufo bufo) native to the UK, has been reportedly facing major declines within the last decade (Wilkinson, 2019). Although there are potentially numerous, non-mutually exclusive causes of these declines, one particular concern is the effect of microplastics (MP) (Boyero et al., 2020). Over the last decades plastic production and use have increased exponentially, resulting in large quantities of plastic waste (Geyer et al., 2017). Plastic waste that ends up in aquatic environments can be broken down into smaller particles by chemical and photochemical reactions (Güven et al., 2017). Frogs can ingest MPs directly or via prey, these accumulate in the tissues and can impair survival, body condition and function (Boyero et al., 2020) However, little is known about the multi-stressor effect of MPs interacting with gastrointestinal parasites. The presence of these parasites is predicted to influence the retention of MPs in the gastrointestinal tract by increasing the surface area for adhesion and retention (ex., Hernandez-Milian et al., 2019). Additionally, they can also act as a vector for other contaminants, such as pathogens increasing transmission between individuals (Gkoutselis et al., 2021). MPs are ubiquitous, abundant and persistent over time, which highlights the need for understanding these multi-stressor effects in declining populations of common toads.

Aim

1) To investigate the effect of microplastic (MP) ingestion and accumulation on common toad body condition and gastrointestinal parasite composition.

Objectives

1) To assess MPs in the freshwater breeding habitats of common toads in urban and rural areas.

2) To characterise the type of MPs present in the gastrointestinal tract of common toads collected from these breeding sites.

3) To identify the gastrointestinal parasite composition of common toads from different breeding sites.

4) To determine individual common toad body condition in relation to type and number of MPs identified in the gastrointestinal tract.

5) To determine individual common toad parasite composition in relation to type and number of MPs identified in the gastrointestinal tract.

6) Thorough analysis of the data and literature leading to publication.

References:

Boyero, L., López-Rojo, N., Bosch, J., Alonso, A., Correa-Araneda, F. and Pérez, J., 2020. Microplastics impair amphibian survival, body condition and function. Chemosphere, 244, p.125500.

Geyer, R., Jambeck, J.R. and Law, K.L., 2017. Production, use, and fate of all plastics ever made. Science advances, 3(7), p.e1700782.

Gkoutselis, G., Rohrbach, S., Harjes, J., Obst, M., Brachmann, A., Horn, M.A. and Rambold, G., 2021. Microplastics accumulate fungal pathogens in terrestrial ecosystems. Scientific Reports, 11(1), p.13214.

Güven, O., Gökdağ, K., Jovanović, B. and Kıdeyş, A.E., 2017. Microplastic litter composition of the Turkish territorial waters of the Mediterranean Sea, and its occurrence in the gastrointestinal tract of fish. Environmental pollution, 223, pp.286-294.

Hernandez-Milian, G., Lusher, A., MacGabban, S. and Rogan, E., 2019. Microplastics in grey seal (Halichoerus grypus) intestines: Are they associated with parasite aggregations?. Marine Pollution Bulletin, 146, pp.349-354.

Wilkinson, J. 2019. Interviewed by IUCN SSC Amphibian Specialist Group. September 2019, UK.

For more information: For an informal discussion please contact via direct email to Dr Natasha Kruger (N.Kruger@wlv.ac.uk)

Supervisory Team: Dr Timothy Baldwin (Reader in Plant Cell biology), Professor Paul Dupree (University of Cambridge), Professor Peter Williams & Dr Jixin Yang (Glyndwr University)

About the Project:

Acacia senegal is a species of legume, native to the Sahelian region of Africa. When wounded, mature trees of this species secrete a valuable plant gum exudate (termed gum Arabic) to seal the damaged region of the plant. This gum is comprised of a variety of macromolecules commonly associated with the plant cell wall. This exudate has been harvested on a commercial basis for thousands of years and is widely used in the food industry.

The chemical, biochemical and biophysical/physicochemical properties of gum Arabic have been intensively studied for over sixty years. However, little work has been conducted on the cellular and molecular wound response which is responsible for the biosynthesis of the gum. The objectives of the proposed project, therefore, would be to investigate the molecular structure and composition of the plant cell wall in seedlings of this species (Dr Baldwin: University of Wolverhampton), in conjunction with chemical and biochemical analyses of gum samples (harvested from the seedlings’ parent plants) (Professor Williams and Dr Jixin Yang: Glyndwr University). In addition, the proposed project will also include a transcriptomic study of the molecular basis of gummosis that will be performed in the laboratory of Professor Paul Dupree (University of Cambridge).

Methodology

The proposed project will consist of four main areas of study: 1) analytical chemistry/biochemistry 2) light level and transmission electron microscope level immunocytochemistry 3) molecular analyses of gum synthesis.

The initial phase of the project will mainly focus on chemical and biochemical analyses of gum Arabic samples. The bulk of this work will be performed at Glyndwr University in collaboration with Professor Williams and Dr Yang. This will involve the determination of the sugar composition using HPLC, and molecular mass distribution using GPC coupled to MALLS/RI/UV detectors, FTIR etc. The biochemical studies will include determination of total nitrogen content, monosaccharide and amino acid composition analyses, SDS-page, Western blots and immuno-dot blots.

At the same time, Acacia seeds obtained from Nigeria (Rubber Research Institute) will be germinated and the resultant seedlings grown, in the glasshouse facility at UoW. At six months post germination, plant material from the stem and branches from several of the seedlings will be harvested, fixed and embedded in L.R. white resin. The resin embedded samples will subsequently be sectioned and screened against a panel of anti-cell wall antibodies using light level and transmission electron microscope level immunocytochemistry, to investigate the structure and molecular composition of their cell walls.

The final phase of the study will involve an investigation of gene expression related to gum synthesis (using a transcriptomics approach) will be performed on RNA extracted from the A.senegal seedlings, in collaboration with Professor Paul Dupree based at the University of Cambridge.

For more information: For an informal discussion please contact via direct email toDr Timothy Baldwin (T.Baldwin@wlv.ac.uk)

Supervisory Team

Director of Studies: Dr Paul Barrow, Senior Lecturer in Physiology and Pharmacology

About the Project:

The human gastric wall contains a variety of receptors detecting, among other things, temperature, stretch and osmolarity. These are linked to afferents in the autonomic nervous system and cause a variety of systemic consequences, including modulation of cardiac autonomic control resulting in acute changes in heart rate, cardiac output and blood pressure. We have already shown that stimulation of gastric TRPM8 cold receptors by menthol results in an acute increase in cardiac parasympathetic tone and concomitant reduction in heart rate and blood pressure, counteracting the increase in cardiac sympathetic activity caused by gastric stretch via TRPV4 receptors when both receptors are stimulated by a cold meal (Kazadi et al., 2018. https://doi.org/10.1113/EP087058). Using analysis of respiratory sinus arrhythmia as a measure of cardiac parasympathetic tone (Task Force of the European Society of Cardiology et al., 1996. https://doi.org/10.1161/01.CIR.93.5.1043) and QTc analysis of ECG as a measure of cardiac sympathetic tone, you will further investigate the effects of other gastric receptor activation on acute cardiac autonomic control. Research will be undertaken in the physiology research laboratory on the Wolverhampton City campus. This research will lead to the submission of a thesis for the award of Doctor of Philosophy (PhD) and will be published at research conferences and in scientific journals as the data warrant.

For more information: For an informal discussion please contact via direct email to Dr Paul Barrow (p.a.barrow@wlv.ac.uk)

Supervisory Team: Dr Stefano Vaglio (Reader in Animal Behaviour), Dr Colin Dubreuil (Lecturer in Conservation Biology), Dr Andrew Gascoigne (Senior Lecturer Mathematics & Computer Science), Dr Jacob Dunn (Associate Professor in Evolutionary Biology – Anglia Ruskin University)

About the Project:

Modern zoos are involved in captive breeding and reintroduction programmes and, thus, play a pivotal role in fighting biodiversity loss. However, several endangered animal species are currently showing a low success rate in captive breeding, which impair them from possibly serving as a buffer against extinction. In the zoo environment, the lack of stimuli and the repetitive routine can lead to boredom and to the display of stereotypic behaviours, as well as endocrinological dysfunction, which may be linked with decreased reproductive fitness of captive populations. Nevertheless, captivity is a human-controlled environment and, therefore, it is possible to enhance captive breeding via evidence-based facilitation of reproductive behaviours and environmental enrichments.

This project aims to develop novel techniques for captive animal welfare based on the supervisory team experience in olfactory and acoustic communication. We will initially focus our research on critically endangered primate species that can be difficult to breed and maintain in captivity (i.e., lemurs and tamarins). The PhD student will gather behavioural data and samples for analysis, focussing on two main areas of research for commercialisation:

1) Olfactory enrichment: the PhD student will study the scent-marking behaviour of primate groups and, with the assistance of zoo staff, will gather olfactory samples for laboratory analysis. The chemical profiles of the samples will be examined using solid-phase microextraction and gas chromatography-mass spectrometry techniques. This will allow for the identification of specific compounds associated with the biology and behaviour of the individual primates. Compounds of interest (e.g., those relating to female fertility or affiliative behaviour) will then be isolated, synthesised, and used in olfactory enrichment experiments – i.e., presented to other individuals to evaluate their responses. Such approaches have been proven to improve welfare and reproductive success in domestic animal species (e.g., the Feliway© cat calming pheromones on sale to the public), but little is known about this in non-human pr

2) Acoustic communication: the PhD student will study the behaviour of the animals and will simultaneously record all vocalisations using active and passive acoustic recording. This will allow us to analyse individual calls associated with the biology and behaviour of specific individuals. Acoustic data will be analysed, and machine learning methods will be developed to automatically detect and classify calls. We will analyse calls that are related to positive and negative experiences (e.g., feeding vs. aggressive interactions) to understand how acoustic analysis could be used as a novel welfare monitoring technique. Such methods have previously been used with domestic animals (e.g., chickens), but have not yet been implemented in wildlife.

The expected outputs of this project will include:

• Training for the PhD student, who will work with us and learn new field and lab skills.
• Data towards the development of two different technical approaches to animal welfare and conservation (olfactory enrichment and acoustic monitoring).
• Data for high-quality peer-reviewed publications, presenting our findings and supporting an impact case study, currently being developed by Dr Vaglio on the theme of animal welfare and conservation.

For more information: For an informal discussion please contact via direct email to Dr Stefano Vaglio (S.Vaglio@wlv.ac.uk)