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91.
Yang JH Hou JF Farquharson C Zhou ZL Deng YF Wang L Yu Y 《British poultry science》2011,52(4):507-516
1. The aim of this study was to investigate the localisation and expression of the epithelial Ca2+ channel TRPV6 (transient receptor potential vanilloid channel type 6) in different intestinal segments and kidney of laying hens during peak lay. 2. Immunohistochemical analysis of the intestine indicated that TRPV6 was localised to the brush-border membranes of the duodenum, jejunum, ileum, caecum, and rectum. Expression was weaker in the rectum, and little or no expression was found in crypt and goblet cells. In addition, TRPV6 mRNA was quantified amongst different intestinal segments, and expression was highest in the duodenum and jejunum. Furthermore, Western blotting indicated that the duodenum expressed the greatest amount of TRPV6 and the rectum the least with the other segments expressing intermediate levels. 3. In the kidney, distinct immunopositive staining for TRPV6 was detected at the apical domain of the distal convoluted tubules (DCT) and medullary connecting tubules (CNT). Interestingly, distribution of TRPV6 extended to the proximal convoluted tubules (PCT). Furthermore, the kidney expressed lower TRPV6 mRNA and protein levels compared with that in the duodenum. 4. In conclusion, the epithelial Ca2+ channel TRPV6 is strongly expressed in the apical cells of the entire intestine and the renal tubules, suggesting that active Ca2+ transcellular transport plays a crucial role in dietary calcium (re)absorption in laying hens. 相似文献
92.
Dietary supplementation with Acanthopanax senticosus extract enhances gut health in weanling piglets
Jun Fang F.Y. Yan X.F. Kong Z. Ruan Z.Q. Liu R.L. Huang T.J. Li M.M. Geng F. Yang Y.Z. Zhang Peng Li Joshua Gong G.Y. Wu M.Z. Fan Y.L. Liu Y.Q Hou Y.L. Yin 《Livestock Science》2009,123(2-3):268-275
The present study was conducted to investigate the effects of Acanthopanax senticosus extract (ASE) as a dietary additive on gut health in weanling piglets by examining diarrhea frequency, intestinal microbiota and morphology. A total of 96 Duroc× (Landrace × Yorkshire) piglets weaned at 21 days of age with an average initial body weight (BW) of 5.6 ± 0.4 kg were randomly assigned to 3 treatment groups with 4 duplicates of 8 piglets each. The piglets were fed basal diet to which had been added 0 or 1 g/kg of ASE, or 0.7 g/kg antibiotics, respectively. Fecal consistence was monitored twice daily and the frequency of diarrhea was calculated. On day 21 after the initiation of supplementation, 8 piglets were randomly selected from each treatment group (2 piglets per pen) and slaughtered. The jejunum, ileum, colon and cecum were then excised and fixed in 10% neutral formalin solution to determine villus height and crypt depth, after their contents were collected to determine microbiota. The results showed that dietary supplementation with ASE increased (P < 0.05) the density of bacterial populations that co-migrated with Lactobacillus amylovorus, Lactobacillus salivarius, Bacillus subtilis, and Clostridium lituseburens, but decreased (P < 0.05) those co-migrating with Staphylococcus aureus, Salmonella typhimurium, Ruminococcus forques, and E. coli O157:H7 in the PCR-DGGE profiling analysis when compared with the control group. The villus height of the duodenum, jejunum and ileum increased (P < 0.05) by 14.8, 13.7 and 10.0%, while the crypt depth decreased (P < 0.05) by 17.9, 9.1 and 12.1%, respectively, in response to dietary ASE supplementation. Additionally dietary supplementation with ASE or an antibiotic decreased (P < 0.05) the frequency of diarrhea by 55.6 and 52.2%, respectively, compared with the control group. In conclusion, these findings suggest that dietary supplementation with ASE could regulate the microbiota composition and maintain a normal morphology of gut mucosa in weanling piglets, thereby decreasing diarrhea that resulted from weaning stress. 相似文献
93.
94.
A novel dendrimeric peptide induces high level neutralizing antibodies against classical swine fever virus in rabbits 总被引:1,自引:0,他引:1
Li GX Zhou YJ Yu H Li L Wang YX Tong W Hou JW Xu YZ Zhu JP Xu AT Tong GZ 《Veterinary microbiology》2012,156(1-2):200-204
The amino acid sequence (TAVSPTTLR, 829-837aa) on the glycoprotein E2 of classical swine fever virus (CSFV) is a conserved and linear neutralizing epitope. In the present study, two peptides were constructed based the core sequence of this neutralizing epitope, the dendrimeric peptide (Th-B(4)) containing four copies of B cell epitope fused to one copy of promiscuous T helper (Th) cell epitope and the peptide Th-B containing a single copy of B cell epitope fused to one copy of Th cell epitope. The dendrimeric peptide Th-B(4) elicited high titers of neutralizing antibodies as detected in an indirect ELISA, blocking ELISA and neutralization test and induced a complete protection against CSFV C strain in rabbits. The Th-B elicited low titers of neutralizing antibodies and did not induce a protection in rabbits. These results suggest that the dendrimeric peptide Th-B(4) may be a promising marker vaccine candidate against CSFV and the multimerization is a requirement for development of a peptide vaccine. 相似文献
95.
2014年从山东省外观健康的牛羊采集鼻拭子样品共707份,提取其RNA,用流感病毒特异性引物进行RT-PCR检测。对RT-PCR扩增的阳性产物进行序列测定,意外发现其中1份羊拭子样品含有羊边界病病毒,并且该结果得到其他试验验证。结合我国2012年首次在安徽和江苏两地检出该病毒,以及当前我国羊群流通情况,推测该病毒可能在我国有所存在。该调研结果对分析各类RT-PCR检测的假阳性产生原因,有参考意义。并提示RT-PCR检测结果难以作为疫病或感染病诊断的确切依据。其诊断结果有时需要用荧光探针或测序进行进一步鉴定。 相似文献
96.
试验选用72头(61.32±1.14)kg杜长大肥育猪,随机分成3个处理,每个处理4个重复(栏),每个栏6头猪。3个处理分别饲喂基础日粮+0.30 mg/kg亚硒酸钠、基础日粮+0.30 mg/kg酵母硒Ⅰ、基础日粮+0.30 mg/kg酵母硒Ⅱ。正试试验期6周。试验结束后从每个重复选择体重基本一致的试验猪各1头,前腔静脉采血后屠宰取背最长肌,测定肌肉和血清中谷胱甘肽过氧化物酶活力、总过氧化物歧化酶活力、丙二醛含量和总抗氧化能力。结果表明:与亚硒酸钠相比,酵母硒Ⅱ提高了血清和肌肉中谷胱甘肽过氧化物酶和总过氧化物歧化酶活力活力(P<0.05),降低了丙二醛水平(P<0.05),显著提高了血清的总抗氧化能力(P<0.05)。 相似文献
97.
<正>2009年生猪存出栏稳定增长,猪饲料消费量稳步增加,对赖氨酸的需求起到了较大的促进作用。然而,2009年国内赖氨酸也继续面临供应、库存双增加的局面,这也是国内赖氨酸价格持续低迷的重要原因。 相似文献
98.
猪、鸡间空肠弯曲杆菌感染分布状况的调查研究 总被引:1,自引:0,他引:1
目的:对入沪28个产地(河南开封、山东青岛、江苏南通、浙江金华、上海奉贤等地)的鸡、猪进行了空肠弯曲杆菌流行分布调查,了解空肠弯曲杆菌在不同动物种间的分布状况。方法:以空肠弯曲杆菌特异性的VS1基因为扩增目标片段,对2005~2007年间在上海市三家家禽市场和五家生猪屠宰场采集的2234(鸡1015份、猪1219份)盲肠内容物样品进行PCR检测。结果:鸡盲肠内容物检出空肠弯曲杆菌阳性的样品288份,平均阳性率为28.4%,猪盲肠内容物检出空肠弯曲杆菌阳性的样品420份,平均阳性率为34.4%。结论:28个产地的鸡、猪均有空肠弯曲杆菌感染,不同产地、种属其感染率和发病情况不同,经统计学分析显示,猪的感染阳性率显著高于鸡,上海市内(奉贤等地)来源的畜禽感染阳性率显著低于浙江金华、江苏海门、江苏张家港和江苏大丰等外省市地区。 相似文献
99.
J. Deng X. Wu S. Bin T.‐J. Li R. Huang Z. Liu Y. Liu Z. Ruan Z. Deng Y. Hou Y.‐L. Yin 《Journal of animal physiology and animal nutrition》2010,94(2):220-226
Experiments were conducted to determine the effects of feeding different starch sources on piglets. Four diets were formulated with maize, brown rice, sticky rice and Hi‐Maize 1043 as starch sources, with resistant starch (RS) contents of 2.3%, 0.9%, 0.0%, 20.6%, and amylose and amylopectin ratio of 0.23%, 0.21%, 0.18%, 0.06% respectively. Fifty‐six pigs weaned at 28 days of age were randomly assigned to one of the four diets. In Exp. 1, six piglets in each group were fitted with an indwelling jugular catheter. After 25 days of feeding trial, venous blood samples were obtained at time zero and every 1 h for 4 h. In Exp. 2, the remaining piglets were used to determine the effects of different starch sources on the fractional synthesis rate (FSR). The results indicated that feeding the Hi‐Maize 1043 diet decreased (p < 0.05) plasma contents of glucose, insulin, lactic acid and T3, while sticky rice increased plasma contents of glucose and insulin. The insulin contents in piglets fed the sticky rice diet was 69.2 μIU/ml at 1 h post‐feeding which was highest among the starch diets. The FSR in the pancreas, spleen, duodenum, jejunum, ileum and colon in the corn group were much higher (p < 0.05) than that in the sticky rice group. These results suggest that RS is potentially beneficial for improving insulin sensitivity in young pigs and that the ratio of amylose and amylopectin have significantly effects on the FSR in splanchnic tissues in weaned piglets. Another finding of this study indicated maize with a ratio of amylose and amylopectin of 0.23 has the best starch sources for pig production. 相似文献
100.
经过对加利福尼亚兔进行3个世代纯种选育后,繁殖性能有了明显的改善。三世代窝产仔数、产活仔数、35日龄断奶窝重分别为7.73只、7.33只、3733.64g,分别较零世代提高10.4%、11.6%和69.8%,在CP16.13%、CF14.5%的中等偏下营养条件下,四世代77日龄体重达1915g,35~77日龄日增重为27.11克,屠宰率达56.2%,兔群整齐度有明显的改善。 相似文献