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71.
72.
本试验旨在研究饲粮添加不同剂量25羟基维生素D3[25(OH)VD3]对断奶前犊牛生长性能、营养物质表观消化率、血浆代谢物及粪便菌群的影响。选取18头健康、体重[(40.68±1.20)kg]相近的新生荷斯坦犊牛,随机分为3个组,每组6头牛。对照组饲喂基础饲粮,不添加25(OH)VD3;试验组每头犊牛每天分别在基础饲粮中添加6000(低剂量组)和12000 IU(高剂量组)的25(OH)VD3。试验期56 d。结果表明:1)与对照组相比,低剂量组和高剂量组体重和平均日增重显著提高(P<0.05),高剂量组体高显著提高(P<0.05),低剂量组和高剂量组粪便评分显著降低(P<0.05)。2)与对照组相比,低剂量组和高剂量组干物质表观消化率显著提高(P<0.05),高剂量组中性洗涤纤维(P=0.05)和钙表观消化率(P<0.05)显著提高。3)与对照组相比,低剂量组和高剂量组血浆25(OH)VD3和钙含量显著提高(P<0.05),高剂量组血浆磷含量显著提高(P<0.05)。4)与对照组相比,低剂量组和高剂量组血浆白细胞介素-2含量显著降低(P<0.05)。5)与对照组相比,低剂量组和高剂量组粪便中毛螺菌科(Lachnospiraceae)和普雷沃式菌科(Prevotellaceae)相对丰度显著提高(P<0.05),粪便中鼠杆菌科(Muribaculaceae)、克里斯滕森菌科(Christensenellaceae)、螺旋体科(Spirochaetaceae)和未培养_细菌_o_柔膜菌纲_RF39(uncultured_bacterium_o_Mollicutes_RF39)相对丰度显著降低(P<0.05)。由此可见,饲粮添加25(OH)VD3可以提高断奶前犊牛生长性能,促进营养物质消化吸收,降低炎症反应,改善粪便菌群,降低腹泻发生。 相似文献
73.
74.
NAN Wen-jin HU Hong-hui WU Jing-bo HUANG Jian-qiang PENG Guo-liang XIAO Zheng-zhong 《中国畜牧兽医》2017,44(6):1769-1777
In order to understand the main pathogen of newborn piglets diarrhea in North Guangdong region, 31 diarrhea samples were collected from six pig farms in North Guangdong, the pathogen of porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV) and porcine rotavirus (PoRV) were detected by Real-time RT-PCR, meanwhile, ORF3 gene of PEDV amplified from positive samples were sequenced and analyzed. Pathogen detection results showed that 83.87%(26/31) samples were positive for PEDV, all herds and samples were negative for TGEV and PoRV. The sequence analysis revealed that the ORF3 gene of 5 epidemic strains of PEDV were all 675 bp, homologies of nucleotides were 98.7% to 100.0%, and homologies with reference sequences of nucleotides were 94.5% to 100.0%, and some gene mutation in common nucleotides site. The results of gene phylogenetic trees showed that PEDV could be divided into two groups, PEDV genetic relationship between field strains in North Guangdong and some regions in China, Southeast Asia, North America, Europe from 2013 to 2015 was closer, classed as a gene subgroup, from 2011 to 2012 main epidemic strains in our country and vaccine strains classed as other two gene subgroups. These results indicated that PEDV infection was the main pathogen of newborn piglets diarrhea in North Guangdong region, as time passed, the PEDV epidemic strains gene presented a tendency of evolution and variation. 相似文献
75.
76.
为研究As2O3对实验兔生长和繁殖性能的影响,选择年龄和体重相近的40只实验兔(32只母兔,8只公兔)随机分成4组.对照组饲喂不含As2O3的基础日粮,试验Ⅰ组、试验Ⅱ组和试验Ⅲ组分别饲喂含As2O3 0.5mg/kg、1.0mg/kg和1.5mg/kg的日粮.生长发育和繁殖性能的测定结果显示,试验Ⅰ组与对照组相比,差异不显著(P>0.05),试验Ⅱ组性能表现优于对照组,差异显著(P<0.05),试验Ⅲ组出现中毒症状.本实验表明,适量的As2O3对实验兔生长和繁殖具有促进作用. 相似文献
77.
78.
N-methyl-D, L-aspartate (NMA) elicited secretion of growth hormone (GH)-releasing hormone from both the hypothalamic-preoptic area and the median eminence that were collected from boars. We suggest that the previously described increase in GH secretion that follows peripheral treatment of swine with NMA is attributable, at least in part, to NMA-stimulated secretion of GH-releasing hormone from the central nervous system. 相似文献
79.
《The Journal of Applied Poultry Research》2009,18(2):143-150
The present study was conducted to investigate the effect of feeding Camelina sativa to layer birds on egg production, egg quality characteristics, egg lipids, and fatty acid and lipid oxidation products. Fifty-eight-week-old ISA Brown Leghorn laying hens (n = 48) were kept in individual cages and were fed a corn- and soybean meal-based diet with added Camelina meal at 0%, (control), 5%, (CAM5), 10% (CAM10), and 15% (CAM15). The experimental diets were fed for a period of 80 d. Hen-day egg production was lowest for CAM15 (P < 0.05). A significant reduction in yolk weight was observed for CAM10 and CAM15 eggs when compared with control eggs (P < 0.05). Yolk weight, as a percentage of egg weight, was lower for CAM10 and CAM15 eggs, whereas albumen weight, as a percentage of egg weight, was higher in CAM10 and CAM15 eggs than in control eggs (P < 0.05). The yolk:albumen ratio was higher in control eggs than in CAM10 and CAM15 eggs (P < 0.05). Egg total fat content was lowest for CAM15 eggs and was 31.5, 31.9, 30.8, and 29.5 for control, CAM5, CAM10, and CAM15 eggs, respectively (P < 0.05). Total n-3 fatty acids constituted 0.32% in control eggs compared with 2.54, 2.69, and 2.99% in CAM5, CAM10, and CAM15 eggs (P < 0.05). An 8-fold increase in docosahexaenoic acid was observed in CAM15 eggs when compared with control eggs (P < 0.05). The n-6:n-3 ratio was 14.8, 5.6, 4.6, and 4.3 for control, CAM5, CAM10, and CAM15 eggs, respectively (P < 0.05). Total saturated fats were lowest for CAM5 and CAM10 eggs. Eggs from the CAM15 regimen had higher TBA-reactive substance values (P < 0.05) than those from the CAM5, CAM10, or control regimen. Camelina meal could be incorporated into poultry rations as a source of energy, protein, and essential n-3 and n-6 fatty acids. However, inclusion of more than 10% Camelina meal in the hen diet may affect egg lipid quality aspects. Therefore, measures for minimizing lipid peroxidation should be used to enhance egg quality and lipid stability. 相似文献
80.
Fernando A. Muoz Sergio Estrada-Parra Andres Romero-Rojas Thierry M. Work Erik Gonzalez-Ballesteros Iris Estrada-Garcia 《Veterinary immunology and immunopathology》2009,131(3-4):211-217
To understand the role of the immune system with respect to disease in reptiles, there is the need to develop tools to assess the host's immune response. An important tool is the development of molecular markers to identify immune cells, and these are limited for reptiles. We developed a technique for the cryopreservation of peripheral blood mononuclear cells and showed that a commercially available anti-CD3 epsilon chain antibody detects a subpopulation of CD3 positive peripheral blood lymphocytes in the marine turtle Chelonia mydas. In the thymus and in skin inoculated with phytohemagglutinin, the same antibody showed the classical staining pattern observed in mammals and birds. For Western blot, the anti-CD3 antibodies identified a 17.6 kDa band in membrane proteins of peripheral blood mononuclear cell compatible in weight to previously described CD3 molecules. This is the first demostration of CD3+ cells in reptiles using specific antibodies. 相似文献