ABSTRACT Routine blood analysis indicated the presence of Mycoplasma-like bodies in a guigna (Leopardus guigna). Evidence of infection with Candidatus Mycoplasma haemominutum was found in blood samples using PCR and DNA sequencing of the 16S rRNA gene of Mycoplasma. Mycoplasma spp. are documented in cats but their role in the transmission of Mycoplasma to guigna populations requires investigation.

Abstract Extracellular vesicles are nanoparticles secreted by cell and have been proposed as suitable markers to identify competent embryos produced in vitro. Characterizing EVs secreted by individual embryos is challenging because culture medium itself contributes to the pool of nanoparticles that are co-isolated. To avoid this, culture medium must be depleted of nanoparticles that are present in natural protein source. The aim of this study was to evaluate if the culture medium subjected to nanoparticle depletion can support the proper in vitro development of bovine embryos. Zygotes were cultured in groups on depleted or control medium for 8 days. Nanoparticles from the medium were characterized by their morphology, size and expression of EVs surface markers. Isolated nanoparticles were labelled and added to depleted medium containing embryos at different developmental stages and evaluated after 24 hours at 2, 8-16 cells, morula and blastocyst stages. There were no statistical differences on blastocyst rate at day 7 and 8, total cell count neither blastocyst diameter between groups. However, morphological quality was better in blastocysts cultured in non-depleted medium and the expression of SOX2 was significantly lower whereas NANOG expression was significantly higher. Few nanoparticles from medium had a typical morphology of EVs but were positive to specific surface markers. Punctuated green fluorescence near the nuclei of embryonic cells was observed in embryos from all developmental stages. In summary, nanoparticles from culture medium are internalized by in vitro cultured bovine embryos and their depletion affects the capacity of medium to support the proper embryo development.

Abstract: Adipose tissue derived mesenchymal stem cells (AMSCs) had been isolated and used for cell therapy in domestic cats. For wild cats, the isolation of AMSCs has only been reported in the black-footed cat (Felis nigripes). AMSCs obtained from wild cats may be useful to treat injuries of endangered cat species that remain in captivity or arrive at wildlife rehabilitation centers. Additionally, AMSCs might allow improvement of cloning techniques or assist in derivation of induced pluripotent stem cells. Endangered wild cats such as the guigna (Leopardus guigna), an endemic and endangered species from Chile and Argentina, might benefit greatly from the development of novel treatments or techniques that can be applied for its conservation. The objective of this study was to characterise putative AMSCs from guigna in terms of their main biological attributes, particularly, growth kinetics, differentiation ability and surface marker expression. Results obtained from this characterisation were compared with AMSCs isolated from domestic cats. AMSCs were isolated from peritoneal adipose tissue of female cats and subcutaneous tissue from a female guigna. Migration potential, colony-forming unit assay, mesodermal differentiation and surface marker expression (CD45, CD44, CD90, MHCI and MHCII) were evaluated. Domestic cat and guigna AMSCs displayed similar growth properties in culture. Both AMSC types showed mesodermal differentiation potential, in vitro homing potential and similar surface marker expression. These results indicate that AMSCs from subcutaneous tissue of guigna could have potential use as regenerative treatment for this species and might be considered for use in other biotechnological applications.