Kenneth Jeffries
Photo of Kenneth Jeffries

Assistant Professor

Office W477 Duff Roblin
(204) 474-6429

Environmental and anthropogenic stressors can disrupt homeostasis and negatively affect aquatic organisms, potentially leading to impacts on growth, reproduction and survival over time. The focus of my research is to investigate how various environmental and contaminant stressors can affect an individual's fitness through examination of responses at cellular, tissue and whole organism levels of biological organization, and how these responses can potentially scale up to population level consequences. I use genomics techniques to characterize the cellular responses of fishes to abiotic (e.g., temperature, salinity), biotic (e.g., pathogens) and anthropogenic (e.g., wastewater, endocrine disrupting compounds, pesticides, pharmaceuticals) stressors relevant to aquatic ecosystems. I integrate these cellular level responses with tissue or whole organism level performance indices to gain a more comprehensive understanding of the effects of exposure to environmental stressors and to address whether populations and species can persist in changing or disturbed aquatic environments. This work has focused on non-model fishes that are economically important, invasive or of conservation concern and combines approaches used in the fields of physiology, ecological genomics, fish ecology and ecotoxicology. I have recently begun examining how exposure to environmental stressors affects the expression of immune response genes and increases the susceptibility of stressed individuals to pathogen infections, a potentially significant and undetected cause of fish mortality in disturbed ecosystems. I am moving towards using next generation sequencing approaches to examine how genome variation leads to different phenotypic responses to aid in predicting which populations and species will be able to tolerate future changes in environmental conditions. Because of the widespread influence of climate change, environmental disturbances and the impacts of human activity on ecosystems, much of this research is applicable for studying aquatic systems throughout North America.

Selected Publications

Jeffries, Ken M, Connon, Richard E, Davis, Brittany E, Komoroske, Lisa M, Britton, Monica T, Sommer, Ted, Todgham, Anne E and Fangue, Nann A (2016). Effects of high temperatures on threatened estuarine fishes during periods of extreme drought. Journal of Experimental Biology 219 (11), 1705–1716.

Komoroske, Lisa M, Connon, Richard E, Jeffries, Ken M and Fangue, Nann A (2015). Linking transcriptional responses to organismal tolerance reveals mechanisms of thermal sensitivity in a mesothermal endangered fish. Molecular Ecology 24 (19), 4960–4981.

Jeffries, Ken M, Hinch, Scott G, Gale, Marika Kirstin, Clark, Timothy D, Lotto, Andrew G, Casselman, Matthew T, Li, Shaorong, Rechisky, Erin L, Porter, Aswea D, Welch, David W and et al. (2014). Immune response genes and pathogen presence predict migration survival in wild salmon smolts. Molecular Ecology 23 (23), 5803–5815.

Jeffries, Ken M, Hinch, Scott G, Sierocinski, Thomas, Pavlidis, Paul and Miller, Kristi M (2014). Transcriptomic responses to high water temperature in two species of Pacific salmon. Evolutionary Applications 7 (2), 286–300.

Research Interests

Biodiversity, Ecology and Environment, Physiology, Molecular Ecology, Transcriptomics, Conservation Physiology, Threatened Fishes, Ecotoxicology

Recent Publications

  • Brander, Susanne M, Jeffries, Ken M, Cole, Bryan J, DeCourten, Bethany M, White, J Wilson, Hasenbein, Simone, Fangue, Nann A and Connon, Richard E (2016). Transcriptomic changes underlie altered egg protein production and reduced fecundity in an estuarine model fish exposed to bifenthrin. Aquatic Toxicology 174, 247–260.
  • Clark, Timothy D, Furey, Nathan B, Rechisky, Erin L, Gale, Marika K, Jeffries, Ken M, Porter, Aswea D, Casselman, Matthew T, Lotto, Andrew G, Patterson, David A, Cooke, Steven J and et al. (2016). Tracking wild sockeye salmon smolts to the ocean reveals distinct regions of nocturnal movement and high mortality. Ecological Applications 26 (4), 959–978.
  • Cole, Bryan J, Brander, Susanne M, Jeffries, Ken M, Hasenbein, Simone, He, Guochun, Dennison, Michael S, Fangue, Nann A and Connon, Richard E (2016). Changes in Menidia beryllina gene expression and in vitro hormone receptor activation after exposure to estuarine waters near treated wastewater outfalls. Archives of Environmental Contamination and Toxicology 71, 210–223.
  • Jeffries, Ken M, Connon, Richard E, Davis, Brittany E, Komoroske, Lisa M, Britton, Monica T, Sommer, Ted, Todgham, Anne E and Fangue, Nann A (2016). Effects of high temperatures on threatened estuarine fishes during periods of extreme drought. Journal of Experimental Biology 219 (11), 1705–1716.
  • Komoroske, Lisa M, Jeffries, Ken M, Connon, Richard E, Dexter, Jason, Hasenbein, Matthias, Verhille, Christine and Fangue, Nann A (2016). Sublethal salinity stress contributes to habitat limitation in an endangered estuarine fish. Evolutionary Applications 9 (8), 963–981.

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We are recruiting a motivated postdoc to join the laboratories of Drs. Ken Jeffries, Jason Treberg and Darren Gillis at the University of Manitoba. The postdoc’s primary focus will be synthesizing and linking metabolic indices and transcriptomic profiles with differences in movement patterns in walleye from what may be genetically distinct populations. Experience with the analysis of transcriptomics data or large data sets on animal movement is desirable.

Important Dates

March 20: Start of Summer term registration

March 30: Good Friday (University Closed)

April 1: Easter Sunday (University Closed)

Upcoming Seminars

General seminar: Stephanie Tkachuk, MSc Defense: “A forward genetic screen for Caenorhabditis elegans pharyngeal gland cell defects and characterization of mutagenized strains with a homozygous viable gland cell under migration” — Friday, March 23 at 2 p.m., 304 Biological Sciences.

General seminar: Dr. Virginia Trimble: “TBA” — Friday, March 23 at 3 p.m., 527 Buller.

General seminar: Dr. Paul Cremer: “TBA” — Friday, April 6 at 3 p.m., 527 Buller.