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81.
82.
选用4头带有瘤胃瘘管的内蒙古白绒山羊作为瘤胃液供体羊,以两种不同精粗比的粗料型日粮为培养底物,研究不同苹果酸添加量(0、3、6、9、12mmol/l)对内蒙古白绒山羊瘤胃挥发性脂肪酸动态变化的影响。结果表明:不同精粗比日粮下乙酸、丙酸、丁酸及TVFA浓度均以3:7日粮组较高,乙丙比以2:8日粮组较高,差异均不显著(P>0.05)。添加苹果酸后,3:7日粮组乙酸、丙酸浓度在培养4、8、18和24h后显著升高(P<0.05);丁酸浓度3mmol/l组高于对照组,9mmol/l组低于对照组,差异均不显著(P>0.05);而2:8日粮组乙酸、丙酸浓度在培养8、18h后显著升高(P<0.05);丁酸浓度在培养8、12和24h后升高,但差异不显著(P>0.05);乙丙比在两种日粮下均极显著降低(P<0.01);TVFA浓度在两种日粮下均升高,培养4、8、18h差异是显著的(P<0.05)。 相似文献
83.
对70头山羊、50头绵羊和5头奶山羊进行了人工培植羊黄研究。在植黄后一年,对42头山羊,10头绵羊和1头奶山羊取黄,在羊的胆囊内形成了羊黄。对11个羊黄样品进行了胆色素、总胆固醇和总胆酸等项目测定,结果表明与天然牛黄主要成分相同,但含量有所不同。对5个羊黄样品进行了超微结构观察,结果与天然牛黄一致。 对人工培植羊黄羊的胆囊胆汁进行了测定,β-葡萄糖醛酸苷酶活性(以下简称β-G酶活性)和粘蛋白含量明显升高。因接种的大肠杆菌血清型不同,β-G酶活性也呈现不同程度的变化。对培植羊黄羊的胆囊进行了组织学检查,胆囊壁粘膜上皮柱细胞间的杯状细胞及固有膜中的粘液腺大量增生,是胆汁中多糖粘蛋白增高的组织学基础。 对培植羊黄进行了药理学试验,其结果与天然牛黄完全一样。 相似文献
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ABSTRACT1. Prolactin hormone (governed by the PRL gene) is secreted by the anterior pituitary of animals, which combines with its receptor (prolactin receptor, PRLR) to act on target cells. Both PRL and PRLR are mainly associated with reproductive performance. The genetic mechanism of nesting in poultry is not yet clear, and so the aim of the current study was to determine expression patterns of PRL and PRLR at different times across the breeding stages of black Muscovy ducks.2. In this study, the CDS regions of PRL and PRLR were determined by RACE sequencing. The expression levels of PRL and PRLR in the pituitary, ovary and uterus from the black Muscovy duck were compared and analysed during the pre-laying, laying and nesting periods.3. The results showed that PRL and PRLR are highly homologous in a variety of poultry species. The expression of the PRL gene in the pituitary was the highest, which was significantly higher than seen in the ovary and uterus. This trend ran through the entire prenatal period, i.e. the laying period and the nesting period. The expression level of the PRLR gene in the pituitary and ovary was generally low, and expression in the uterus was the highest. There was no significant difference in expression of the PRLR gene between pituitary and ovary during different periods, but the expression level of the PRLR gene in the uterus reached its highest level during the nesting stage, which was significantly higher than seen in the early laying period. 相似文献
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Xu YN Cui XS Sun SC Lee SE Li YH Kwon JS Lee SH Hwang KC Kim NH 《The Journal of reproduction and development》2011,57(1):143-150
Mitochondria are important regulators of both apoptosis and autophagy. One of the triggers for mitochondrial-mediated apoptosis is the production of reactive oxygen species (ROS), which include hydrogen peroxide, superoxide, hydroxyl radical, nitric oxide and peroxynitrite. Recently, several studies have indicated that ROS may also be involved in the induction of autophagy. In the present study, we used H(2)O(2) to induce mitochondrial stress, examined apoptotic- and autophagic-related gene expression and observed LC3 protein (autophagosome presence marker) expression in porcine parthenotes developing in vitro. In porcine four-cell parthenotes cultured for 5 days in NCSU37 medium containing 0.4% BSA, the developmental rate and mitochondrial distribution did not differ from that of the group supplemented with 100 μM H(2)O(2) but was significantly decreased in the group supplemented with 500 μM H(2)O(2) (P<0.05). Transmission electron microscopy (TEM) indicated that whereas normal shaped mitochondria were observed in blastocysts from the control group, abnormal mitochondria (mitophagy) and autophagic vacuoles were observed in blastocysts from the group that received 500 μM H(2)O(2). Furthermore, addition of H(2)O(2) (100 μM and 500 μM) decreased cell numbers (P<0.05) and increased both apoptosis (P<0.05) and LC3 protein expression in the blastocysts. Real-time RT-PCR showed that H(2)O(2) significantly decreased mRNA expression of anti-apoptotic gene Bcl-xL but increased pro-apoptotic genes, Caspase 3 (Casp3) and Bak, and autophagy-related genes, microtubule-associated protein 1 light chain 3 (Map1lc3b) and lysosomal-associated membrane protein 2 (Lamp2). However, the addition of H(2)O(2) had no effect on mRNA expression levels in nuclear DNA-encoded mitochondrial-related genes, cytochrome oxidase (Cox) 5a, Cox5b and Cox6b1, in blastocysts. These results suggest that H(2)O(2) leads to mitochondrial dysfunction that results in apoptosis and autophagy, which is possibly related to porcine early embryo development. 相似文献
89.
Hongzhi Xiao Pan Sun Feifei Sun Jicheng Qiu Jie Wang Jianzhong Wang Yalong Lin Xiaohui Gong Lu Zhang Suxia Zhang Xingyuan Cao 《Journal of veterinary pharmacology and therapeutics》2019,42(6):660-664
Altrenogest, a synthetic progestogen, is characterized by its estrus synchronization in mares, ewes, sows, and gilts. To investigate the pharmacokinetic profile and evaluate its accumulation in gilts, 18 oral doses of 20 mg altrenogest/gilt/day were given to eight healthy gilts at an interval of 24 hr. Plasma samples were collected, and altrenogest was determined by ultra‐high‐performance liquid chromatography with mass spectrometry. WinNonlin 6.4 software was used to calculate the pharmacokinetic parameters through noncompartmental model analysis. After the first administration (D 1), the pharmacokinetic parameters, including Tmax, Cmax, and the elimination half‐life (T1/2λz), were similar to those observed after the final administration (D 18). However, the mean residence time at D 1 was significantly lower than D 18. As a whole, the mean steady‐state plasma concentration (Css), degree fluctuation (DF), accumulation factor (Rac), and area under the plasma concentration–time curve in steady state (AUCss) were 22.69 ± 6.15 ng/ml, 270.64 ± 42.51%, 1.53 ± 0.23, and 544.63 ± 147.49 ng hr/ml, respectively. These results showed that after 18 consecutive days of oral administration of altrenogest, plasma concentrations of altrenogest had a certain degree of fluctuation, without significant accumulations. 相似文献
90.