Quantitative and descriptive histological aspects of jaguar (Panthera onca Linnaeus, 1758) ear skin as a step towards formation of biobanks

Abstract

Skin of mammals vulnerable to extinction, such as the jaguar, is used as a source of material in conservation strategies. The composition of skin is not uniform among species, and the ability to distinguish similarities in skin morphology in animal groups is fundamental in the application of skin tissue for use in biobanks. The aim of our study was to evaluate the structure, composition and capacity for culture of ear skin from the yellow and black jaguars. Both qualitative and quantitative methods were used, focusing on skin thickness, cell quantification and distribution, collagen density, proliferative activity and viability. Histomorphometrical study of the skin showed a total thickness of 273.2 and 274.6 µm for the yellow and black jaguars, respectively. Melanocytes and fibroblasts were, respectively, 9.7 and 23.0 for the yellow jaguar and 11.3 and 26.8 for the black jaguar. A collagen density of 67.0% and 49.0% was observed for yellow and black jaguars, respectively. Both animals presented a proliferative activity varying between 1.20 and 1.30. All tissues could promote cellular detachment, reaching subconfluence in 10–15 days. This kind of information from histomorphometrical features and cell cultures can be essential for a more targeted application of ear skin cryopreservation in this species, as such information will enable understanding the action of substances on tissues during the conservation process.

Evaluation of the damage caused by in vitro culture and cryopreservation to dermal fibroblasts derived from jaguars: An approach to conservation through biobanks

“…In this context, two factors are crucial-the conditions of in vitro culture and cryopreservation. Recently, our group established primary culture conditions for jaguar cells by evaluating these cells until the first passage (Praxedes et al, 2020). However, studies in different mammals have shown that somatic cells may lose their viability and functions following extended in vitro culture (Magalhaes et al, 2017;Tian et al, 2003).…”

Ultrastructural and morphometric description of the ear skin and cartilage of two South American wild histricognate rodents (Dasyprocta leporina and Galea spixii)

“…Variations in the thickness of the epidermal layers of the skin of the neck, thorax, and carpus of male and female paca (C. paca) have also been described in the study by Isola et al (2013). These variations observed in the agouti and spix's yellowtoothed cavy epidermis are important, since they will allow determination of cryoprotective agents that should be used in the cryopreservation of the skin (Praxedes et al 2020).…”

“…However, epidermal cells, such as Langerhans and Merkel cells, in spix's yellow-toothed cavy were found to be smaller. In general, different cellular proportions of the epidermis have also been observed for other species, such as rodents, felids and domestic mammals, such as the common mole rat (C. hottentotus), naked mole rat (H. glaber) (Daly & Buffenstein 1998), jaguar (Panthera onca) (Praxedes et al 2020), cats, dogs (Souza et al 2009) and pigs (Navarro et al 2001). This cellular variation observed both in agoutis and spix's yellow-toothed cavy for other species may be associated with the need in the skin to protect itself from the environment, specifically, from ultraviolet rays, since melanin synthesized from melanocytes of the epidermis has this function (Khavkin & Ellis 2011, Dolka et al 2014).…”

Evaluation of different skin regions derived from a postmortem jaguar, Panthera onca (Linnaeus, 1758), after vitrification for development of cryobanks from captive animals

“…Tissue fragments from all experimental groups were submitted to histological processing according to Praxedes et al, (2019Praxedes et al, ( , 2020.…”