Collection, long-term preservation, and in vitro culture of sheep testis as model species for endangered deer species

• Grant number: 24/04621-4
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: July 30, 2024
• End date: October 31, 2024
• Field of knowledge: Biological Sciences - Genetics - Animal Genetics
• Principal Investigator: José Maurício Barbanti Duarte
• Grantee: Eluzai Dinai Pinto Sandoval
• Supervisor: Pierre Comizzoli
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Institution abroad: Smithsonian Conservation Biology Institute (SCBI), United States
• Associated to the scholarship: 23/07473-3 - Development of protocols for conservation and culture of cells to obtain cytogenetic preparations in Cervids, BP.PD

Abstract

Sheep is a domestic ruminant species used as experimental model for studying reproductive, metabolic and in vitro-growing features of non-domestic ruminant species. Therefore, it is an optimal model to develop collection, long-term preservation and in vitro protocols for testicular tissue of neotropical deer aiming to properly storage it in cryobanks for conservation purposes. The main objective of this study is to establish and measure different cryopreservation protocols (in association with different cryoprotectants) for testicular tissue from domestic sheep as model species for endangered neotropical deer. Testicular tissue will be collected from domestic sheep adult males and dissected in small fragments to allocated it in one of the following experimental groups: no cryopreservation (control); exposure to dimethyl sulphoxide (DMSO), glycerol (GLY) or ethylene glycol (EG) followed either by slow freezing (SF), or conventional vitrification (CV). Tissues will remain cryopreserved in cryotubes for at least one week. After thawing, we will investigate the effects of cryopreservation protocols on testis histomorphology, cell viability, proliferative potential, and mitochondrial activity of testicular cells. Statistical analysis will be performed to compare the effects of the cryopreservation technique on testicular parameters using SAS version 8.0. The results will suggest clear direction to optimize sheep testicular tissue survival allowing us to make comparative analysis of collection and long-term preservation methods that may be applied on somatic and reproductive tissue samples from endangered neotropical deer species.