Assessment of the incidence of Pythium insidiosum on the banks of the Tietê River in the Botucatu/SP region and possible associated environmental factors

• Grant number: 21/14378-1
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): January 01, 2023
• Effective date (End): August 31, 2023
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Preventive Veterinary Medicine
• Principal Investigator: João Pessoa Araújo Junior
• Grantee: Gabriel Gasparini Camargo
• Host Institution: Instituto de Biociências (IBB). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Oomycetes are microorganisms from the Kingdom Stramenopila, phylogenetically close to brown algae and diatoms, and that have some fungal-like characteristics, such as heterotrophic nutrition, hyphae-shaped vegetative growth and similar ecological niches. Some species of oomycetes can be plant and animal parasites. Representative of oomycetes, Pythium insidiosum is the etiological agent of pythiosis, a disease capable of affecting several species of domestic and wild animals, as well as humans, having been reported in different countries with tropical climate. The biology of P. insidiosum includes phases of sexual and asexual reproduction, and in the asexual phase, biflagellate zoospores are produced. These zoospores are released into the aquatic environment and seek to establish themselves in plant substrates as part of their life cycle, in addition to having chemotaxis for keratinous substrates. Despite knowledge about the life cycle of P. insidiosum, biotic and abiotic factors for the establishment of the pathogen in the environment are poorly understood. Lentic environments, such as reservoirs and riverbanks, are suitable environments for the study of biotic and abiotic factors related to the establishment of P. insidiosum in these environments. The detection and isolation of P. insidiosum from the environment by conventional methods, such as the use of baits or bait (for example, hair strands, snake ecdysis) and the use of selective culture media, are ineffective due to their low sensitivity. Currently, new techniques for detection and monitoring of microorganisms have been used, providing satisfactory results and a high degree of sensitivity. The collection of environmental-DNA (eDNA) from the environment and application of the qPCR (Real-Time Quantitative Polymerase Chain Reaction) technique, associated with the baiting method, can contribute to the evaluation of the presence of the microorganism in the environment, enabling the monitoring of P. insidiosum in different environments, as well as helping to understand environmental factors that may be associated with its presence.