Lungworm parasite intensity and its association with the endocrine and immune systems and energy reserves in male cane toads

Main Article Content

Sandra Elizabeth Hernández Méndez, Dr
Corad Sernia, Prof
Victor Hugo Reynoso Rosales, Dr
Adrian John Bradley, Dr

Abstract

Host-parasite interactions can be harmful or harmless depending on the fitness and stress levels of the organisms. Interactions between the endocrine system, the immune system and energy expenditure are critical in the maintenance of homeostasis during stressful periods in vertebrates. We examined whether lungworm loads (Rhabdias spp.) of male cane toad (Rhinella marina) sampled during the wet season from three different populations, are associated with hormone levels, immune competence, and metabolic status. We found evidence of direct and strong associations between parasite burdens and variables related to hormonal levels, metabolic status and immune competence. We also found that interrelationships among independent variables can change the strength of the association with lungworm loads. These findings suggest that high levels of corticosterone affect immune competence against parasites, both directly and by inducing changes in the metabolic status of the animals. Additionally, high testosterone levels during the reproductive season, influenced variables related to metabolic status, which will also lead to higher parasite loads. Overall, we conclude that the endocrine system and metabolic status in male cane toads are critical to the immune competence against parasites during the reproductive season.

Keywords:
Rhinella marina, corticosterone, immune-competence, energetic-status, Rhabdias spp

Article Details

Author Biographies

Sandra Elizabeth Hernández Méndez, Dr, Professor

Facultad de Medicina Veterinaria y Zootecnia Universidad Autónoma de Tamaulipas 

Corad Sernia, Prof, Honorary Associate Professor

School of Biomedical Sciences

The University of Queensland

Victor Hugo Reynoso Rosales, Dr, Instituto de Biología UNAM

Departamento de Zoología

Instituto de Biología de la UNAM

Adrian John Bradley, Dr, Honorary Associate Professor

School of Biomedical Sciences, The University of Queensland

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