Can a deadly fungal disease affect the metabolic rate of Plethodon cinereus?

Rubino, Christopher

Can a deadly fungal disease affect the metabolic rate of Plethodon cinereus?

Persistent URL

https://hdl.handle.net/10456/57591

Author(s)

Rubino, Christopher

Date Issued

April 1, 2024

Abstract

Vertebrates produce an immune response when a pathogen is detected in the body. These immune responses can have metabolic costs because of the need to produce leukocytes, cytokines, and antibodies to fight off the pathogen. Specifically, in most vertebrates, when a pathogen is present, an immune response is produced, ultimately increasing the metabolic rate to provide energy for this biological process. This increase in metabolism directly affects other physiological processes in the body of the infected individual, such as growth, lack of movement, and reproduction. This mechanism is referred to as a trade-off and is important because it can increase an organism's chance of survival. Ectothermic organisms, such as amphibians, have been known to use trade-offs in nature due to stress and infectious diseases. An infectious disease driving amphibians to utilize these physiological trade-offs is an emerging fungal disease, Batrachochytrium dendrobatidis, a chytrid fungus that is the main driver for the decline of over 350 amphibian species. Chytridiomycosis, a fungal disease, attacks the microbiota on the keratinized skin of metamorphosed amphibians and mouthparts of tadpoles, causing water loss, lethargy, and difficulty in oxygen exchange. Although this fungal disease causes amphibian declines, few species have evolved to clear the infection. One species that can clear this infection is a terrestrial salamander, Plethodon cinereus. This salamander has shown to be highly resistant to Bd because of its cutaneous bacteria on its microbiome. This cutaneous bacteria on its skin may allow for less metabolic costs during infection and therefore have fewer physiological trade-offs. To further study why this salamander is highly resistant to Bd, I assessed the metabolic rate of Bd-exposed and non-exposed salamanders. I predicted to find that Bd-exposed salamanders would have similar metabolic rates as the control salamanders. These data show that Bd-exposed salamanders had lower metabolic rates than control salamanders. These results negate the previous literature on this topic and suggest that these salamanders may be significantly useful in understanding other properties of Bd.

Major

Biology

First Reader(s)

Venesky, Matthew D.