Effects of Vitrification Techniques on the Formation of Skin Cryobank of the Ocelot (Leopardus Pardalis)

Abstract

BACKGROUND: Skin cryobanks represent important tools for the conservation of the maximum genetic representation of a population, especially those with a certain degree of threat to extinction, such as the ocelot. A relevant step towards the proper establishment of these banks is the definition of adequate cryopreservation techniques for the conservation of the skin. OBJECTIVE: We evaluated the effects of two different techniques [direct vitrification in cryovials (DVC) and solid-surface vitrification (SSV)] for the preservation of ear skin derived from ocelot. MATERIALS & METHODS: For both techniques, we vitrified the ear skin using Dulbecco's modified Eagle's medium with 3.0 M dimethyl sulfoxide, 0.25 M sucrose, and 10% fetal bovine serum. Non-cryopreserved tissues were used as control (control group). All tissues were analyzed for their morphometric characteristics by conventional histology and morphological/functional analysis by cell ability during the culture. RESULTS: While tissues cryopreserved by DVC showed similar values for dermis thickness and number of perinuclear halos to the control, tissues cryopreserved by SSV showed similarities to the control regarding the number of melanocytes, percentage of collagen fibers, and numbers of viable cells by apoptosis analysis. Additionally, none of the vitrification techniques affected stratum corneum thickness, number of keratinocytes, tissue proliferative activity, cell viability, or metabolism. CONCLUSION: Both vitrification techniques (DVC and SSV) can be used for the conservation of ocelot skin; however, SSV guarantees a higher cellular quality after in vitro tissue culture in most of the parameters evaluated, such as viability, metabolism, and apoptosis analysis.