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The correlation between apoptosis and early bovine embryonic loss is still not fully elucidated. In the present study, the relationship between the arrest of bovine embryos at the different stages of development and apoptosis was evaluated. We used embryos 7 days after in vitro maturation and fertilization, and morphologic and biochemical apoptotic analyses were performed by using a phase contrast microscope and by the terminal transferase dUTP nick end‐labelling respectively. For the statistic, the apoptotic cell ratio (ACR) was determined as the percentage of apoptotic cells per embryo. To evaluate the relation between ACR and fragmentation pattern, embryos were divided into five groups, groups I–V. To assess the relation between ACR and cytoplasmatic fragmentation, embryos were divided into three groups, according to the fragmentation percentage (<5%; 5–15% and >15%). Of the total 139 embryos included, 65 arrested at 2–8 cells; 14 arrested at 9–16 cells; 18 compacted morula and 42 were non‐arrested blastocysts. The average number of embryonic fragmentation at different stages of the development, 2–8 cells, 9–16 cells, compacted morula and blastocyst, was 16.0 ± 1.5, 28.7 ± 4.4, 4.4 ± 2.4 and 1 ± 0.3 respectively. The embryos at the stage of arrested 9–16 cells and compacted morula had higher ACR than those at the blastocyst stage, excluding the stage of 2–8 cells (the genome is not yet active). The correlation detected between embryonic development and ACR was 0.92 (p < 0.01). It was observed that embryos possessing high fragmentation showed the higher ACR value (r = 0.98, p < 0.05). Comparing the results between fragmentation percentage and ACR, it was observed that the embryos with higher percentage of fragmentation corresponded to higher ACR (r = 0.97, p < 0.01). These results clearly demonstrated that bovine embryonic arrest at different stages of development is correlated with the apoptotic mechanisms.  相似文献   
3.
Melatonin, the major secretory product of the pineal gland, scavenges a variety of reactive oxygen and nitrogen species in vivo and in vitro, indicating that melatonin is a potent function as an antioxidant. The objective of this study was to investigate the effect of melatonin in the presence or absence of hydrogen peroxide (H2O2) on sperm characteristics (motility, viability, survival rate, membrane integrity, lipid peroxidation (LPO) and mitochondria activity) and also to examine the developmental rates to the blastocysts stage of porcine oocytes fertilized in vitro with semen treated with or without melatonin (100 nm ) in the presence or absence of H2O2 (250 μm ). The sperm were treated with melatonin in the presence or absence of H2O2 for 3, 6, 9 and 12 h at 37°C and then analysed for the sperm characteristics. The porcine embryos were produced by in vitro maturation and in vitro fertilization (IVM/IVF) using semen treated with or without melatonin (100 nm ) in the presence or absence of H2O2 (250 μm ) for 6 h. The semen characteristics, including motility, viability, survival rate, membrane integrity and mitochondria activity, were higher in the groups that were treated with melatonin in comparison to other groups, irrespective of incubation periods. Malondialdehyde levels in control, melatonin and melatonin + H2O2 groups were lower than H2O2 only group. A positive correlation was shown among motility, viability, survival rate and membrane integrity, but a negative correlation was observed between LPO and the other evaluation methods. The developmental rates to blastocysts of IVM/IVF porcine oocytes fertilized by semen treated with melatonin were significantly increased compared with any other groups, with the cell number of blastocysts shown to have a similar trend to the developmental rates. These results demonstrate that melatonin can improve the semen characteristics during in vitro storage and support the developmental ability of IVM/IVF embryos in pigs.  相似文献   
4.
The aim of the present study was to elucidate the fundamental mechanism of bovine oviduct epithelial cell (BOEC) co‐culture on developmental capacity of bovine in vitro oocyte maturation/in vitro fertilization (IVM/IVF) embryos. We examined the effects of astaxanthin against nitric oxide‐induced oxidative stress on cell viability by MTT assay, lipid peroxidation (LPO) by using thiobarbituric acid (TBA) reaction for malondialdehyde (MDA) and the expression of antioxidant genes (CuZnSOD, MnSOD and Catalase) or apoptosis genes (Bcl‐2, Caspase‐3 and Bax) by RT‐PCR in BOEC. We also evaluated the developmental rates of bovine IVM/IVF embryos co‐cultured with BOEC pre‐treated with astaxanthin (500 μm ) in the presence or absence of sodium nitroprusside (SNP, 1000 μm ) for 24 h. Cell viability in BOEC treated with SNP (50–2000 μm ) lowered, while astaxanthin addition (50–500 μm ) increased it in a dose‐dependent manner. Cell viability in astaxanthin plus SNP (1000 μm ) gradually recovered according to the increase in astaxanthin additions (100–500 mm ). The LPO in astaxanthin group (50–500 μM) gradually decreased in a dose dependent manner and among SNP or astaxanthin plus SNP group, SNP alone and astaxanthin (50 μM) plus SNP shown a significant increase than other groups (p < 0.05). Expression of apoptosis or antioxidant genes was detected by RT‐PCR. Bcl‐2 and antioxidant genes were detected in astaxanthin or astaxanthin plus SNP group, and Caspase‐3 and Bax genes were only found in SNP group. When bovine IVM/IVF embryos were cultured for 6–7 days under co‐culture system such as BOEC treated with astaxanthin in the presence or absence of SNP, the developmental ability to blastocysts in 500 μm astaxanthin group was the highest of all groups. These results suggest that astaxanthin has a antioxidative effect on cell viability and LPO of BOEC, and development of bovine IVM/IVF embryos due to the induction of antioxidant genes and suppression of apoptosis genes.  相似文献   
5.
A 5‐year‐old male Miniature Schnauzer was presented with unilateral cryptorchidism and signs of feminization. Abdominal ultrasonography revealed an enlarged right testis and a large, fluid‐filled cavity that appeared to arise from the prostate. Computed tomography revealed the cavity to be consistent with an enlarged uterine body, arising from the prostate, and showed two structures resembling uterine horns that terminated close to the adjacent testes. The dog had a normal male karyotype, 78 XY. Gonadohysterectomy was performed and both the surgical and the histological findings confirmed the presence of a uterus in this male animal, resulting in a diagnosis of persistent Mullerian duct syndrome (PMDS). The enlarged intra‐abdominal testis contained a Sertoli cell tumour. Computed tomography proved to be an excellent diagnostic tool for PMDS.  相似文献   
6.
ObjectiveTo determine the analgesic and systemic effects of epidural administration of ketamine, lidocaine or a combination of ketamine/lidocaine in standing cattle.Study designProspective, randomized, experimental trial.AnimalsSix healthy male cattle weighing between 335 and 373 kg.MethodsThe animals received 0.5 mg kg?1 of ketamine (K), 0.2 mg kg?1 of 2% lidocaine (L) or 0.25 mg kg?1 ketamine plus 0.1 mg kg?1 lidocaine (KL). All the drugs were injected into the dorsolumbar epidural space via a caudal approach through a non‐styletted multiple‐port catheter. Each animal received each treatment at random. Evaluations of analgesia, sedation, ataxia, heart rate, arterial pressure, respiratory rate, skin temperature and rectal temperature were obtained at 0 (basal), 5, 10, 15, 30, 45, 60, 75, 90 minutes after epidural injection, and then at 30‐minute intervals until loss of analgesia occurred. Skin temperature was taken at these intervals up to 60 minutes. All the animals received a standard noxious stimulus; a 4‐point scale was used to score the response. A second scale was used to score ataxia and a third for sedation.ResultsThe duration of analgesia in the upper and lower flanks in cattle was 140 ± 15, 50 ± 14 and 80 ± 22 minutes (mean ± SD) after dorsolumbar epidural KL, K or L, respectively. The cardiovascular changes were within acceptable limits in these clinically healthy cattle.ConclusionsDorsolumbar epidural administration of KL to cattle resulted in longer duration of analgesia of the upper and lower flanks in standing conscious cattle, than the administration of K or L alone.Clinical relevanceFurther research is necessary to determine whether this combination using this technique provides sufficient analgesia for flank surgery in standing cattle.  相似文献   
7.
H. J. Crofts 《Euphytica》1989,44(3):225-234
Summary An international survey of wheat breeders and scientists was conducted to determine whether there was a common understanding of the term winter wheat. Response to photoperiod was mentioned by only seven of the 30 survey respondents. It was consequently suggested that it be excluded from any definition. Response to vernalization was mentioned by 28 of the 30 respondents. However, there was considerable variation in the method of quantifying this response and the degree of response necessary for wheat to be called winter. It was concluded that the only objective and internationally consistent definition of winter wheat was a genetic definition based on the complement of Vrn genes a wheat possesses. Varieties not possessing any of the dominant Vrn alleles appear to take a distinctively longer and more variable time to head when grown under non-vernalizing, long day conditions. These are genetically winter wheats.  相似文献   
8.
Studies were conducted to examine the effects of the cyclicity and the presence of a dominant follicle (DF) in ovary on the recovery and in vitro growth of pre-antral follicles (PFs) in sheep and buffalo. Small pre-antral follicles (SPFs, 100–250 μm) and large pre-antral follicles (LPFs, 250–450 μm) were isolated from slaughterhouse ovaries in the breeding seasons by a mechanical and enzymatic method. The sheep and buffalo PFs were cultured in vitro for 6 and 15 days, respectively, and examined for their growth, survival and antrum formation rates and growth rates of oocytes in cultured pre-antral follicles. The follicles of the sheep and buffalo were recovered and cultured simultaneously within replicates. The recovery rates (number per ovary) of both SPFs and LPFs were significantly (p < 0.05) higher in cyclic ewes (SPFs: 22.0 ± 3.3 vs 12.1 ± 2.6 and LPFs: 16.0 ± 3.6 vs 9.2 ± 1.8) and buffaloes (SPFs: 9.2 ± 1.3 vs 4.1 ± 1.0 and LPFs: 10.3 ± 2.7 vs 5.4 ± 0.7) compared with those recovered from acyclic ones. Presence of a DF in ovary significantly (p < 0.05) reduced the recovery rates of LPFs in ewes (9.06 ± 2.7 vs 16.4 ± 3.8) but had no effect in buffalo. Cyclicity of animals or follicular dominance had no effects on in vitro growth, survival and antrum formation rates and growth rates of oocytes in cultured PFs of SPFs and LPFs in both sheep and buffalo. The in vitro growth, survival and antrum formation rates of LPFs and growth rates of oocytes in cultured LPFs were significantly (p < 0.05) higher than those observed in SPFs in both sheep and buffalo. The overall recovery and growth rates of the PFs were lower in buffaloes compared with ewes.  相似文献   
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10.
  1. The waters of the Patagonian Shelf in the south-west Atlantic are nutrient rich, support large concentrations of wildlife, and are exploited by several fisheries, including the large Asian squid-jigging fishery. Although the squid-jigging fishery has previously been observed to have few problems with the accidental mortality of seabirds, the deliberate catch for consumption of seabirds by the crew has been identified as a possible issue.
  2. Four cruises were made between Uruguay and the Falkland Islands during 2005–2006 to quantify the impact of jiggers on seabirds from indirect observation platforms. Monitoring included closely approaching 116 jigging vessels and boarding seven for inspection.
  3. The use of non-jigging fishing gear, either for catching fish or seabirds, was observed at the stern of 33 vessels. Twelve seabird carcasses were observed floating close to vessels during 13 days of monitoring. Although the results recorded here are not sufficient to put a confident estimate on the magnitude of this mortality, the density of carcasses floating in the water among the jigging fleet indicated the potential significance of this problem.
  4. The results were considered sufficiently concerning for the Falkland Islands Government to take preventative actions, including educational efforts, improving humanitarian conditions onboard vessels, introducing relevant legislation and licence conditions, and prosecuting intentional seabird take inside the Falkland Islands jurisdiction. This has resulted in the apparent elimination of these mortalities within Falkland waters since the late 2000s.
  5. Nevertheless, it is likely that the same initial conditions exist for the crews of squid jiggers on vessels operating on the high seas, and so the possibility of the targeting of seabirds for consumption continues. Squid fisheries with substantial numbers of jiggers overlap with important foraging areas for a range of albatross and other species in high-seas areas such as the Patagonian Shelf, the Humboldt and Kuroshio currents, and the south-west Pacific Ocean. These areas of overlap may be important to investigate, especially in the foraging grounds of declining seabirds.
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