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Effects of adding different concentrations of melatonin (10?7, 10?9 and 10?11 M) to maturation (Experiment 1; Control, IVM  + 10?7, IVM  + 10?9, IVM  + 10?11) and culture media (Experiment 2; Control, IVC  + 10?7, IVC  + 10?9, IVC  + 10?11) were evaluated on in vitro bovine embryonic development. The optimal concentration of melatonin (10?9 M) from Experiments 1–2 was tested in both maturation and/or culture media of Experiment 3 (Control, IVM  + 10?9, IVC  + 10?9, IVM /IVC  + 10?9). In Experiment 1, maturated oocytes from Control and IVM  + 10?9 treatments showed increased glutathione content, mitochondrial membrane potential and percentage of Grade I blastocysts (40.6% and 43%, respectively). In Experiment 2, an increase in the percentage of Grade I blastocysts was detected in IVC  + 10?7 (43.5%; 56.7%) and IVC  + 10?9 (47.4%; 57.4%). Moreover, a lower number and percentage of apoptotic cells in blastocysts were observed in the IVC  + 10?9 group compared to Control (3.8 ± 0.6; 3.6% versus 6.1 ± 0.6; 5.3%). In Experiment 3, the IVC  + 10?9 treatment increased percentage of Grade I blastocysts with a lower number of apoptotic cells compared to IVM /IVC  + 10?9 group (52.6%; 3.0 ± 0.5 versus 46.0%; 5.4 ± 1.0). The IVC  + 10?9 treatment also had a higher mRNA expression of antioxidant gene (SOD 2) compared to the Control, as well as the heat shock protein (HSPB 1) compared to the IVM  + 10?9. Reactive oxygen species production was greater in the IVM /IVC  + 10?9 treatment group. In conclusion, the 10?9 M concentration of melatonin and the in vitro production phase in which it is used directly affected embryonic development and quality.  相似文献   
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This study evaluated the reproductive performance of gilts inseminated at three intervals before ovulation (0-12, 13-23, 24-30 h) with sperm doses (SD) stored for 0-48 and 96-120 h. A total of 218 PIC Camborough 22 gilts were inseminated once with SD of 1.5 x 10(9) sperms. Pregnant gilts (n = 166) were slaughtered 30.8 +/- 3.7 days after artificial insemination. The number of corpora lutea (CL) and total embryos (TE) was counted. Pregnancy rates (PR) were analysed by chi-square test. TE and embryonic survival (ES), obtained as the ratio between viable embryos and CL, were analysed by GLM procedure (SAS) and mean values were compared by Tukey's test. Pregnancy rate was similar among artificial insemination-ovulation (AIOV) intervals when semen was stored for 0-48 h. However, the lowest PR was observed in the 24-30 h AIOV interval with storage time (ST) of 96-120 h (p < 0.05). There was a significant effect of the interaction between ST and AIOV (p < 0.05) on TE and ES variables. Total embryos and ES did not differ (p > 0.05) among AIOV intervals in ST of 0-48 h. However, gilts inseminated at 24-30 h AIOV interval with ST of 96-120 h showed a reduction of 6.7 embryos (p < 0.05) compared with gilts in the same interval inseminated with semen stored for 0-48 h. ES for the 24-30 h AIOV interval and ST of 96-120 h was lower than that observed in the other groups (p < 0.05).  相似文献   
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复方泛菌克是(犬毒必治)一种新型高效复方抗菌、抗病毒药物,能迅速消除动物肠毒素和内毒素,增强胃肠吸收能力,提高机体免疫功能。试验用犬毒必治对30只患犬细小病毒的病犬进行治疗,治愈28只,死亡2只,治愈率为93.3%。  相似文献   
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  1. Preservation of endangered species is now recognized as a relevant component of regional and global conservation actions achieved through the maintenance of the remaining populations in a favourable conservation status. The Mediterranean common dolphin (Delphinus delphis) is listed as an Endangered subpopulation in the International Union for Conservation of Nature Red List, with declining numbers in some of the areas where it has been studied for numerous years. Prey depletion, fisheries bycatch, pollution, health risks, and climate change are among the recognized threats that the species is facing in the region.
  2. The existing national, regional, and international legislation pertinent to Mediterranean countries should aid greater science–policy–management integration and support innovative research and monitoring towards effective conservation. The challenges inherent in studying the pelagic D. delphis should not preclude the use of long-term, year-round, multiplatform surveys, side by side with the latest molecular tools, which aid our understanding of its populations' genetic diversity, resistance to diseases, and resilience in a semi-enclosed fast-changing sea.
  3. Addressing the multiplicity of problems confronting the species requires collaborative effort at all levels to share and merge resources, data, and expertise more efficiently. In this review, we provide an overview of the current knowledge on the Mediterranean common dolphin, the main threats, and knowledge gaps that are priorities for addressing its conservation, while providing clear recommendations for effectively safeguarding the species and its habitat at both local and regional levels.
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