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261.
X-chromosome inactivation (XCI) is an epigenetic process that equalizes expression of X-borne genes between male and female eutherians. This process is observed in early eutherian embryo development in a species-specific manner. Until recently, various pluripotent factors have been suggested to regulate the process of XCI by repressing XIST expression, which is the master inducer for XCI. Recent insights into the process and its regulation have been restricted in mouse species despite the evolutionary diversity of the process and molecular mechanism among the species. OCT4A is one of the represented pluripotent factors, the gate-keeper for maintaining pluripotency, and an XIST repressor. Therefore, in here, we examined the relation between OCT4A and X-linked genes in porcine preimplantation embryos. Three X-linked genes, XIST, LOC102165544, and RLIM, were selected in present study because their orthologues have been known to regulate XCI in mice. Expression levels of OCT4A were positively correlated with XIST and LOC102165544 in female blastocysts. Furthermore, overexpression of exogenous human OCT4A in cleaved parthenotes generated blastocysts with increased XIST expression levels. However, increased XIST expression was not observed when exogenous OCT4A was obtained from early blastocysts. These results suggest the possibility that OCT4A would be directly or indirectly involved in XIST expression in earlier stage porcine embryos rather than blastocysts.  相似文献   
262.
The embryo culture technique has been improving, but the detailed demands for energy substrates such as glucose, fructose, pyruvate and lactate of preimplantation embryos are still unclear. In the present study, the demands of pig preimplantation embryos at each different developmental stage were investigated by use of parthenogenetic diploids as a model of pig preimplantation embryos. Pig parthenogenetic diploids showed different use of glucose and fructose before and after the 4-cell stage. Although glucose supported the development of pig embryos throughout the preimplantation stages and even maintained the expansion and hatching of blastocysts, it suppressed development to the blastocyst stage when glucose coexisted with pyruvate and lactate from 4 h after activation, but not after 48 h (early 4-cell stage). Since ketohexokinase that metabolizes fructose was not expressed in 2-cell and 4-cell diploids, a medium that included only fructose as a major energy substrate did not support early cleavage of pig diploids beyond the 4-cell stage, and almost no diploids developed to the morula stage just as in a medium without carbohydrates. These results may explain the different suppressive effects on pig preimplantation development between glucose and fructose when pyruvate and lactate were present in a medium. In addition, 4-cell diploids that had been cultured in a medium with pyruvate and lactate developed to the expanded blastocyst stage without any carbohydrates as a major energy substrate. These results show that the demands for carbohydrates are different depending on the developmental stage in pig preimplantation embryos.  相似文献   
263.
Serum samples from 1,011 wild boars hunted in 2012 were collected for serological surveillance for 4 subtypes (pandemic A (H1N1) 2009 and classical H1N1, H1N2 and H3N2) of swine influenza virus (SIV). Samples from 12 of the boars were identified as positive for SIV (pandemic A (H1N1) 2009, n=9; classical H1N1, n=2; and H1N2, n=1) by a hemagglutination inhibition test (HI test) and a nucleoprotein (NP)-based enzyme-linked immunosorbent assay (NP-ELISA). Although the overall seroprevalence of SIV in the Korean wild boar population was somewhat low compared with that in China and the U.S.A., the apparent prevalence of pandemic H1N1 was notable. Therefore, continuous monitoring of the wild boar population is needed as it may be a major reservoir for pandemic H1N1, facilitating its spread to humans and domestic pigs.  相似文献   
264.
Fatalities among avian species due to multiple bee stings are rare. Sixteen pigeons on a farm in Bangladesh each suffered multiple bee stings. Ten of the pigeons died before treatment, 5 (4–11 stings) died within 12 hr after treatment, and 1 pigeon (only 3 stings) survived. Body temperature, heart rate, respiratory rate, hematocrit, hemoglobin, erythrocytes, thrombocytes, MCV, MCH and MCHC decreased significantly after the incident, but leucocytes, heterophils, basophils, eosinophils, monocytes, ALT, AST, LDH, CK, creatinine, BUN and UA increased markedly. Overall, the hematological and biochemical changes in the bee-stung pigeons were similar to those of mammals; however, avian species may be more sensitive to bee stings than mammals.  相似文献   
265.
Between 2011 and 2012, a total of 896 pig fecal samples were collected from nine provinces in Korea, and 50 salmonella enterica susp. enterica serovar Typhimurium (S. Typhimurium) was isolated. The characteristics of the 50 strains were analyzed, and 4 strains were identified as Salmonella enterica subsp. enterica serovar 4,[5],12:i:-. Salmonella 4,[5],12:i:- could not be distinguished from S. Typhimurium through phage typing, antimicrobial resistance testing or multiple-locus variable-number tandem repeat analysis (MLVA). However, among the four Salmonella 4,[5],12:i:- strains, one (KVCC-BA1400078) was identified as a Salmonella 4,[5],12:i:- clone isolated from humans in the United States, and another (KVCC-BA1400080) was identified as DT193, which has been primarily isolated from humans and animals in European countries. The presence of Salmonella 4,[5],12:i:- in Korea poses a significant threat of horizontal transfer between pigs and humans.  相似文献   
266.
Four 1‐week growth trials were conducted to determine the effects of feeding rates on the growth performances of white sturgeon (Acipenser transmontanus) fries 6–9 weeks after initiation of feeding. Six feeding rates with four replications were used in each of the four trials, and the feeding rates were 3.0–8.0, 2.0–7.0, 1.0–6.0 and 1.0–6.0% body weight (BW) per day in 1% increment, respectively. Number of fries per replicate and their initial BW (means ± SEM) were 60, 45, 30 and 30 and 2.8 ± 0.1, 4.5 ± 0.4, 8.5 ± 0.7 and 10.0 ± 0.7 g, respectively. The fries were kept at 18–19 °C and fed a commercial salmonid feed (488 g kg?1 protein and 123 g kg?1 fat). Mortality was low and unrelated to feeding rates. Final body weights, body weight increases, specific growth rates and feed efficiency were significantly (P < 0.05) affected by the feeding rates. Body moisture and lipid contents were significantly affected by feeding rates except body moisture content in trial II. Body protein contents were not affected by feeding rates except in trial III. Broken‐line analysis on specific growth rates indicated that the optimum feeding rates were 6.5 ± 0.4, 4.8 ± 0.2, 4.2 ± 0.1 and 3.8 ± 0.2% body weight per day, respectively, for white sturgeon fries 6–9 weeks after initiation of feeding.  相似文献   
267.
基于SSILP、InDel和SSR标记的杂草稻籼粳分类   总被引:1,自引:0,他引:1  
 采用40对SSILP、30对InDel和43对SSR标记对来自斯里兰卡的28份杂草稻和14栽培稻,来自国内外的9份籼型栽培稻、7份粳型栽培稻和4份代表性杂草稻进行遗传多样性分析。SSILP、InDel和SSR标记分别检测到84、61和213个等位基因,其平均多态性信息含量(PIC)分别为0.257、0.255和0.543。聚类分析显示供试的42份斯里兰卡杂草稻和栽培稻均为籼型。SSILP与InDel标记的相关性很高(r=0.989),而它们与SSR标记相关性较低(0.812和0.808)。结果表明,SSILP和InDel标记可高效鉴别各类稻种资源的籼粳属性,而SSR标记更适用于亚种内的分类。  相似文献   
268.
 利用粳稻品种间杂交组合“龙锦1号/香软米1578”的196份F3家系,对糙米中Fe、Se、Zn、Cu、Mn、Ca、Mg、K、Na和P等10种矿质元素含量的变异及其相关性进行了分析。 10种矿质元素在F3家系间均有较大的变异,其中Na含量变异最大,Zn含量变异最小,变异系数分别为77.69%和12.04%。各矿质元素含量的变异系数大小顺序为Na>Se>Cu>Fe>Mg>Mn>Ca>P>K>Zn。不同矿质元素含量也有较大的差异,F3家系群各矿质元素含量平均值高低排序为P>K>Mg>Ca>Fe>Mn>Zn>Na>Cu>Se。糙米中10种矿质元素含量在F3家系群中均表现为正态分布,为由多基因控制的数量性状。Zn与Fe、Cu,Mn与Mg、Ca、K、P,Ca与Mg、K、Na、P,Mg与K、P,P与K、Na含量呈显著或极显著正相关,而Fe与Se、Mn与Na、Mg与Na含量呈显著或极显著负相关。Mn、Ca、Mg、K、P含量与其他矿质元素含量间的相关关系较Fe、Se、Cu、Zn含量与其他矿质元素含量间的相关关系更为密切。  相似文献   
269.
Recently,thousands of SSR and now SNP markers have been discovered in cotton.Each of these markers provides a valuable molecular tool applying genetic and genomic research to cotton improvement.Cotton DNA marker database (CMD) continues to serve as a molecular marker resource for the cotton research community (http://www.cottonrnarker,org).The current collection of cotton SSR markers oublicly available through CMD is 8,915 and the number continues to grow.  相似文献   
270.
This study examined the analgesic and cardiopulmonary effects of intravenous (IV) tramadol during general intravenous anesthesia in calves. Calves were premedicated with diazepam (0.2 mg/kg, IV) with tramadol (2 mg/kg, IV) (group T) or saline (group S). Anesthesia was induced by thiamylal sodium (4 mg/kg, IV) and maintained with an infusion (2 ml/kg/hr) of 5% guaifenesin containing thiamylal sodium (2 mg/ml). Additional thiamylal sodium (1–2 mg/kg, IV) was administered when interference from the calves was observed during surgery. The total counts of additional thiamylal sodium administration, analgesia score using a visual analog scale, recovery time, and cardiopulmonary function in the different groups were assessed and compared. Group T showed significantly fewer counts of additional drug administration and a significantly higher analgesia score. Tramadol may provide adequate analgesia with minimal cardiopulmonary changes in calves during general anesthesia.  相似文献   
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