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The aim of this study was to assess a vitrification protocol for asinine ovarian tissue, to preserve preantral follicles using different cryoprotectant solutions, composed of various concentrations (EG 3 M or 6 M) of dimethyl sulfoxide or ethylene glycol isolate, or as a combination (DMSO 3 M + EG 3 M). Ten pairs of ovaries from Brazilian north‐eastern breed jennies were obtained through videolaparoscopy, and cortical fragments were submitted to a solid‐surface vitrification (SSV) using each cryoprotectant solution. The ovarian tissue was evaluated for follicular morphology and viability, DNA integrity (TUNEL technique) and the presence of nucleolar organizing regions in granulosa cells (AgNOR technique). After thawing, the percentage of normal preantral follicles was significantly reduced in the vitrified ovarian tissue fragments compared to the fresh control (p < 0.05). When comparing treatments, the use of DMSO 3 M (81.7 ± 37.5%), EG 3 M (83.7 ± 27.4%) and the combination of both DMSO 3 M + EG 3 M (81.8 ± 46.8%) allowed a greater percentage of follicular survival in contrast to DMSO 6 M (69.8 ± 16.5%) and EG 6 M (72.3 ± 18.0%; p < 0.05). When vitrified using the DMSO + EG combination, a higher percentage (62.5 ± 29.1%) of viable follicles (trypan blue) was observed in relation to the other vitrification treatments (p < 0.05). The TUNEL technique identified that all treatments tested showed DNA fragmentation in the follicular cells, except in the case of the DMSO 3 M + EG 3 M treatment. When evaluating the presence of NORs, no significant differences were observed in the amount of NORs between the fresh and vitrified groups using DMSO 3 M + EG 3 M (p > 0.05). We concluded that the combination DMSO 3 M + EG was more efficient for the vitrification of ovarian tissue taken from Equus asinus, allowing adequate preservation of PAFs morphology, viability, DNA integrity and cell proliferative capacity.  相似文献   
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The restoration of native forbs in the Great Basin and similar dryland ecosystems remains a great challenge for land managers. Variable soil water, precocious germination and emergence, and the presence of soil fungal pathogens often reduce plant establishment. Novel restoration treatments that increase soil water during early forb life stages, delay germination and emergence to coincide with favorable spring conditions, and reduce mortality from soil fungal pathogens may benefit native forb restoration. We compared the efficacy of three novel treatments—snow fencing, plant protection fabric, and seed coatings—to improve establishment of a forb species native to the Great Basin, basalt milkvetch (Astragalus filipes Torr. ex A. Gray). We replicated treatments plus a no-treatment control at three sites in the Great Basin in a randomized complete block design over 2 yr. To evaluate the efficacy of our restoration treatments, we measured germination, seedling emergence, establishment, and second-yr survival. The effects of snow fencing and plant protection fabric varied by site and life stage and were likely influenced by the wet spring conditions across sites, particularly the two northern sites. Snow fencing increased establishment and second-yr survival at one site. Plant protection fabric did not benefit any life stage at any site. Seed coatings increased seedling emergence at all sites but did not affect establishment or survival. Overall, second-yr survival remained low across all sites and treatments. Our study indicates that our treatments can positively affect basalt milkvetch emergence, establishment, and survival, but additional management actions are needed to improve long-term restoration success of native forbs.  相似文献   
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