Performance dependent lysine requirement of fattening pigs. 3. Effect of amino acid and energy intake on fat, protein and lysine deposition of swine

The gain in structural matter had a linear course with a corresponding feeding intensity and depending on the period of fattening. However, the animals given high-energy diets deposited 130 g protein per day during the first fattening period, this deposition being compensated in the course of further growth by a considerably lower deposition in the sense of aequifinality. Up to a live weight of 70 kg, animals subjected first to restricted feeding and then to fully balanced feeding revealed the highest protein deposition during the last period of fattening, this fact emphasizing the leanmeat character of the animal material used. The daily fat deposition was found clearly determined by energy intake and independent of amino acid supply. Lysine conversion was influenced by the intake of lysine and energy. Under feeding to norm it reached some 40 and 30% during the first and second periods of fattening, respectively.     

杂交中稻蓄留再生稻两季高产高效施氮技术研究

以杂交中稻组合Ⅱ优602为材料,在头季稻不同施氮量基础上分别设再生稻促芽肥施用量处理,研究了头季稻施氮量和再生稻促芽肥施用量对杂交中稻及其再生稻产量的影响。结果表明,头季稻和再生稻产量均与头季稻施氮量(纯N 0~240 kg/hm2范围内)呈极显著正相关,在头季施纯N 0~180 kg/hm2条件下,与促芽肥施用量呈显著或极显著正相关;头季稻施氮量越高,再生稻高产的促芽肥施用量要求越少。从头季稻与再生稻两季高产和经济施肥的角度考虑,以头季稻施纯氮120~180 kg/hm2,再生稻促芽肥施纯氮135 kg/hm2为佳。     

Regulatory role of l-proline in fetal pig growth and intestinal epithelial cell proliferation

l-proline (Pro) is a precursor of ornithine, which is converted into polyamines via ornithine decarboxylase (ODC). Polyamines plays a key role in the proliferation of intestinal epithelial cells. The study investigated the effect of Pro on polyamine metabolism and cell proliferation on porcine enterocytes in vivo and in vitro. Twenty-four Huanjiang mini-pigs were randomly assigned into 1 of 3 groups and fed a basal diet that contained 0.77% alanine (Ala, iso-nitrogenous control), 1% Pro or 1% Pro + 0.0167% α-difluoromethylornithine (DFMO) from d 15 to 70 of gestation. The fetal body weight and number of fetuses per litter were determined, and the small and large intestines were obtained on d 70 ± 1.78 of gestation. The in vitro study was performed in intestinal porcine epithelial (IPEC-J2) cells cultured in Dulbecco''s modified Eagle medium-high glucose (DMEM-H) containing 0 μmol/L Pro, 400 μmol/L Pro, or 400 μmol/L Pro + 10 mmol/L DFMO for 4 d. The results showed that maternal dietary supplementation with 1% Pro increased fetal weight; the protein and DNA concentrations of the fetal small intestine; and mRNA levels for potassium voltage-gated channel, shaker-related subfamily, member 1 (Kv1.1) in the fetal small and large intestines (P < 0.05). Supplementing Pro to either gilts or IPEC-J2 cells increased ODC protein abundances and polyamine concentrations in the fetal intestines and IPEC-J2 cells (P < 0.05). In comparison with the Pro group, the combined administration of Pro and DFMO reduced the expression of ODC protein and spermine concentration in the fetal intestine, as well as the concentrations of putrescine, spermidine and spermine in IPEC-J2 cells (P < 0.05). Meanwhile, the percentage of cells in the S-phase and the mRNA levels of proto-oncogenes c-fos and c-myc were increased in response to Pro supplementation, whereas depletion of cellular polyamines with DFMO increased tumor protein p53 (p53) mRNA levels (P < 0.05). Taken together, dietary supplementation with Pro improved fetal pig growth and intestinal epithelial cell proliferation via enhancing polyamine synthesis.     

Anatid herpesvirus 1 CH virulent strain induces syncytium and apoptosis in duck embryo fibroblast cultures

Anatid herpesvirus 1 (AHV-1) CH virulent strain was first isolated from an infected duck and it was found that this virus strain could induce cytopathic effect (CPE) in duck embryo fibroblast (DEF). Following AHV-1 infection, DEF showed morphological changes such as cell rounding, improved refractivity and detachment from the culture surface. However, its pathological characteristics were not adequately known. Related studies were performed and the results showed that syncytium formation could be observed as the other type of CPE in AHV-1 infection. Hematoxylin-eosin staining and 4’, 6-diamidino-2-phenylindole (DAPI) staining of infected DEF were each used to visualize the shape and distribution of chromatin within nuclei and nuclear fragmentation was observed. Chromatin condensation and margination, as well as formation of apoptotic bodies were observed by transmission electron microscopy (TEM). DNA ladder formation was detected in AHV-1 infected cells and apoptosis of the infected DEF was also detected by flow cytometry analysis of Annexin V-FITC/PI staining method. Therefore, it was suggested that AHV-1 virulent strain can induce syncytium and apoptosis in DEF. Syncytium formation and apoptosis observed in this study may contribute to the elucidation of AHV-1 pathogenesis.     

去苞叶对玉米子粒脱水过程的影响

为明确苞叶层数对玉米子粒脱水过程的影响,2015-2016年以郑单958和先玉335为试验材料,设置乳熟期（授粉后25~26d）不同程度去苞叶处理,分析苞叶层数对子粒含水率的影响。结果显示：（1）去除1层、2层和3层苞叶后,子粒含水率与同一时期不去苞叶对照差异不显著;去除4~6层苞叶后,子粒脱水过程受到不同程度的影响;去除全部苞叶后,子粒含水率在测定期间始终显著低于对照处理,2个品种表现一致。（2）去除全部苞叶后,郑单958和先玉335百粒干重显著下降,降幅为9.77%~13.29%和15.40%~16.37%,而其他去苞叶处理的百粒干重与对照无显著差异。     

EPS364, a Novel Deep-Sea Bacterial Exopolysaccharide,Inhibits Liver Cancer Cell Growth and Adhesion

The prognosis of liver cancer was inferior among tumors. New medicine treatments are urgently needed. In this study, a novel exopolysaccharide EPS364 was purified from Vibrio alginolyticus 364, which was isolated from a deep-sea cold seep of the South China Sea. Further research showed that EPS364 consisted of mannose, glucosamine, gluconic acid, galactosamine and arabinose with a molar ratio of 5:9:3.4:0.5:0.8. The relative molecular weight of EPS364 was 14.8 kDa. Our results further revealed that EPS364 was a β-linked and phosphorylated polysaccharide. Notably, EPS364 exhibited a significant antitumor activity, with inducing apoptosis, dissipation of the mitochondrial membrane potential (MMP) and generation of reactive oxygen species (ROS) in Huh7.5 liver cancer cells. Proteomic and quantitative real-time PCR analyses indicated that EPS364 inhibited cancer cell growth and adhesion via targeting the FGF19-FGFR4 signaling pathway. These findings suggest that EPS364 is a promising antitumor agent for pharmacotherapy.     

蘑菇渣堆肥做基质对华北落叶松容器苗生长的影响1）

以华北落叶松（ Larix principis-rupprechtii）播种容器苗为研究对象,采用完全随机设计,试验设置6个处理,通过比较苗木形态指标及苗木根系形态结构的差异,研究了添加不同比例的蘑菇渣堆肥对华北落叶松苗木生长的影响。结果表明：基质的密度、pH值、EC值随着蘑菇渣堆肥比例的增加呈现逐渐增大的趋势,总孔隙度、持水孔隙度与对照无显著差异;苗木苗高、地径、生物量及苗木总根长、总根表面积、总根体积随着蘑菇渣堆肥比例增加呈现逐渐减小的趋势;基质中蘑菇渣堆肥比例在0～20％范围内时,苗木形态指标及苗木根系形态结构均与对照无显著差异,基质中蘑菇渣堆肥比例大于30％时,苗木形态指标及苗木根系形态结构与对照出现显著差异,苗木生长受到不利影响。     

玉米秸秆炭和典型农业废弃物混合成型与燃烧特性试验

以玉米秸秆炭和玉米秸秆、苹果枝、沼渣、菌渣为原料,在成型压力为6 MPa的条件下,研究了不同混配比例混合燃料的成型特性,并在此基础上探讨了特定混配比例下的混合样品燃烧特性。研究结果表明:农业废弃物质量分数、种类对混合成型燃料稳定性均有影响,农业废弃物占70%比例时混合成型燃料的抗跌碎强度均大于99.50%;玉米秸秆对成型燃料的稳定性影响最为明显,其质量分数大于30%时,成型燃料抗跌碎强度达到99.68%以上,而沼渣和菌渣质量分数大于50%时,其成型燃料的抗跌碎强度分别超过99.11%和99.71%;苹果枝质量分数大于60%,其成型燃料抗跌碎强度超过99.34%;4种成型燃料的能量密度与原料相比分别提高14.93、11.36、11.74、14.53 GJ/m³;堆积密度分别提高792.99、596.92、605.63、820.12 kg/m³。该研究为农业废弃物新型成型燃料的开发提供了基础支撑。