Cryopreservation of somatic tissue can be applied in biodiversity conservation, especially for wild species as collared peccary. We aimed to evaluate the effect of vitrification techniques of ear tissue of collared peccary [direct vitrification in cryovials (DVC) or solid-surface vitrification (SSV)] on the layers of epidermis and dermis by conventional histology and cell ability during the in vitro culture. Thus, both the vitrification methods were able to maintain normal patterns of the epidermis as the cornea and granular layers, furthermore the intercellular space and dermal-epidermal junction of the spinous layer when compared to fresh control. Nevertheless, DVC and SSV percentage of normality decreased in the morphological integrity of cytoplasm (37.5 and 25.0%) of spinous layer, respectively, as compared to the fresh fragments (100%, p < 0.05). Moreover, other differences between the fresh control (100%) and DVC tissues were verified in the intra-epidermal cleavage of the spinous (37.5%) and basal (37.5%) layers. In general, DVC and SSV techniques were efficient for the recovery of the somatic cells according to most of the evaluated parameters for the in vitro culture (p > 0.05). In addition, only at time of 72 h (D3), in the growth curve, DVC fragments showed a reduced cell concentration than fresh control. In conclusion, SSV was found to be a more efficient method for vitrifying collared peccary skin tissue when compared to DVC. These results are relevant for the tissue cryopreservation from collared peccary and could also be useful for mammals with phylogenetic relationships.

The work aimed (Experiment I) to compare commercial representations of porcine follicle stimulating hormone (FSH, Pluset® vs. Folltropin®) in concentration (10 μg/mL) and time (24 h) standard (more used in protocols of in vitro maturation, IVM); (Experiment II) to evaluate the best incubation time (6 h vs. 16 h vs. 24 h) and, (Experiment III) to analyze varying concentrations (1.0 μg/mL vs. 2.5 μg/mL vs. 10.0 μg/mL) of representations of FSH on the IVM of bovine oocytes. Thus, oocytes were recovered and submitted to IVM under appropriate conditions. After the IVM, oocytes were evaluated for expansion of cumulus cells (CCs), presence of the first polar body (1PB) and metaphase plate (MII). All the data were analyzed by the Fisher exact test (P < 0.05). Initially, in Experiment I, no difference (P > 0.05) was observed in maturation rates of the oocytes incubated with FSH Pluset® or Folltropin®, assessed by expansion of CCs (97.6% vs. 94.3%), presence of 1PB (76.6% vs. 69.4%) and MII (70.0% vs. 68.6%). In Experiment II, when the incubation time with FSH was evaluated, both Pluset® as Folltropin® showed lower rate of expansion of CCs when they were present only in the first 6 h of IVM. As for presence of 1PB, differences were observed in relation to Pluset® while Folltropin® showed similar results in all incubation times. Regarding the MII, no difference was observed between the incubation times with FSH Pluset® and Folltropin®. In Experiment III, no difference was observed in the expansion of CCs, presence of 1PB and MII for concentrations evaluated FSH Pluset® and Folltropin®. Therefore, the FSH Pluset® and Folltropin® have the same efficiency in IVM of bovine oocytes. Regarding the incubation time, it is recommended to maintain FSH (Pluset® or Folltropin®) throughout the period of IVM, since there was no difference in the results of presence of MII. Furthermore, the concentration of 1.0 μg/mL of FSH Pluset® and Folltropin® is as effective as 10 μg/mL and can therefore be used for IVM of oocytes. Key words: Cattle. Gonadotropin. In vitro production of embryos. Oocytes. ResumoO trabalho objetivou (Experimento I) comparar representações comerciais do hormônio folículo estimulante suíno (FSH, Pluset® vs. Folltropin®) na concentração (10 μg/mL) e tempo (24 h) padrão (mais utilizados nos protocolos de maturação in vitro, MIV); (Experimento II) avaliar o melhor tempo de incubação (6 h vs. 16 h vs. 24 h) e, (Experimento III) analisar concentrações variáveis (1,0 μg/mL vs. 2,5 μg/mL vs. 10,0 μg/mL) das representações de FSH sobre a MIV de oócitos bovinos. Para tanto, oócitos foram recuperados e submetidos a MIV em condições adequadas. Após a MIV, oócitos foram avaliados quanto à expansão das células do cumulus (CCs), presença do primeiro corpúsculo polar (1CP) e placa metafásica (MII). Todos os dados foram analisados pelo teste exato de Fisher (P < 0,05).

Animal cloning is a promising technology for biodiversity conservation, and its success depends on the recovery of nucleus donor cells. Specifically for collared peccaries, found sometimes in regions that are difficult to access, the storage at 4-6°C of skin tissues would be an alternative for the conservation of genetic material. Therefore, we aimed to evaluate different storage periods and the presence of a nutrient medium at 4-6°C on the recovery of somatic cells from the skin of collared peccaries. To analyze cell recovery rates, ear explants were distributed in non-refrigerated samples and samples refrigerated for 10, 30, and 50 d in the absence or presence of nutrient medium. All explants were analyzed by histologically and cultured. Only the fragments stored for 50 d without medium showed an increase in the total thickness of skin. Moreover, increased storage period, regardless of the presence of medium, increased the halo number and reduced the metabolic activity. After culture, only the fragments stored without medium for 50 d did not yield any somatic cells. Cells recovered from explants stored for 10 d showed similar characteristics to these recovered from non-refrigerated explants, regardless of the presence of medium, including the day at which explants achieved attachment and the total time to reach subconfluence. In conclusion, viable cells can be recovered from somatic tissues of collared peccaries stored for up to 50 d in the presence of medium, and tissues refrigerated for up to 10 d in the presence of medium yielded more viable cells.

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.

In vitro embryo production (IVEP) contributes to the quantitative and qualitative aspects of animal reproduction. Nevertheless, inherent technical factors such as oxidative stress can negatively influence the result and this can impair cell metabolism, thus decreasing the rates of in vitro development, and necessitating the supplementation of culture medium with antioxidants. In this context, compounds of natural origin with this property have been highlighted because of the positive results obtained at different stages of IVEP. Thus, this review aims to present the results obtained by using natural antioxidants to minimize the effects of oxidative stress on gametes and embryos. A variety of natural isolated substances and mixtures (essential oils and extracts) have been studied for supplementation of IVEP media, at stages of in vitro maturation, sperm capacitation, in vitro fertilization, and in vitro development of embryos in different mammalian species. Generally, beneficial effects are observed according to the concentration used, thus demonstrating the potential of several natural antioxidants. Therefore, the main challenges in using these compounds as antioxidants during IVEP include proving their efficiency against free radicals and determining the best concentration at each stage. In addition, understanding the mechanisms of action of such antioxidants is crucial to establishing their use in IVEP biotechnology. Key words: Culture medium. Natural bioactive. Oxidative stress. Reproduction. ResumoA produção in vitro de embriões (PIVE) contribui para os aspectos quantitativos e qualitativos da reprodução animal. Contudo, fatores inerentes da técnica, como o estresse oxidativo, podem influenciar negativamente o resultado e isso pode prejudicar o metabolismo celular, diminuindo assim as taxas de desenvolvimento in vitro, e exigindo a suplementação do meio de cultivo com antioxidantes. Neste contexto, os compostos de origem natural com essa propriedade têm se destacado devido aos resultados positivos obtidos em diferentes estágios da PIVE. Assim, esta revisão pretende apresentar os resultados obtidos usando antioxidantes naturais para minimizar os efeitos do estresse oxidativo em gametas e embriões. Uma variedade de substâncias isoladas e de misturas naturais (óleos essenciais e extratos) tem sido estudada para a suplementação de meios de PIVE, nas etapas de maturação in vitro, capacitação espermática, fecundação in vitro e desenvolvimento in vitro de embriões em diferentes espécies de mamíferos. Geralmente, os efeitos benéficos são observados de acordo com a concentração utilizada,