实用饲粮补锌对肉鸡组织锌、免疫器官及生产性能的影响

采用实用饲粮（玉米－多饼型,含锌３０ｍｇ／ｋｇ）,对狄高肉鸡（４～６周龄）分别补加锌４０和８０ｍｇ／ｋｇ,研究微量元素Ｚｎ对试鸡组织锌含量、免疫器官生长发育及生产性能的影响。结果表明饲粮缺锌（含Ｚｎ３０ｍｇ／ｋｇ）不影响鸡体重、饲料转化率和心、肝、肾、胰、肌胃、脑千克活体重（Ｐ＞０．０５）,但缺锌影响脾、胸腺、法氏囊、盲肠扁桃体、免疫器官及腺胃、小肠厚度、甲状腺生长发育（Ｐ＜０．０５或Ｐ＜０．０１）;饲粮补锌（４０、８０ｍｇ／ｋｇ）能改善免疫器官机能,增加胫骨、跗骨、趾骨、肝、胰、肾、心组织锌含量（Ｐ＜０．０５或Ｐ＜０．０１）;骨、肝、胰组织对饲粮锌缺乏较敏感,趾骨锌含量是标识鸡锌营养状况的灵敏指标。     

意蜂采用2,3日龄工蜂幼虫产浆的研究

对意蜂采用２和３日龄工蜂幼虫产浆的王台接受率和不同时间取浆浆量进行了研究。研究结果显示：①２日龄工蜂幼虫的王台接受率（８２．４２％）与采用３日龄幼虫的（８１．２１％）无显著差异;②２和３日龄幼虫产浆的台平均产浆量最高峰分别在各自移虫后第６０小时和第４８小时,浆量较高时段分别在移虫后上时和第４２－５４小时;③２日龄幼虫产浆最高时段台平产浆量（０．３７５４ｇ）极显著高于３日龄的（０．３１５７ｇ）但采用     

Effects of road transportation on metabolic and immunological responses in Holstein heifers

This study examined the effects of road transportation on metabolic and immunological responses in dairy heifers. Twenty Holstein heifers in early pregnancy were divided into non‐transported (NT; n = 7) and transported (T; n = 13) groups. Blood was collected before transportation (BT), immediately after transportation for 100 km (T1) and 200 km (T2), and 24 h after transportation (AT). The T heifers had higher (P < 0.05) blood cortisol and non‐esterified fatty acid concentrations after T1 and T2 than did NT heifers. By contrast, the T heifers had lower (P < 0.05) serum triglyceride concentrations after T1 and T2 than had the NT heifers. The serum cortisol and triglyceride concentrations returned (P > 0.05) to the BT concentrations at 24 h AT in the T heifers. The granulocyte‐to‐lymphocyte ratio and the percentage of monocytes were higher (P < 0.05) after T2 in the T heifers than in the NT heifers, suggesting that transportation stress increased the numbers of innate immune cells. T heifers had higher (P < 0.01) plasma haptoglobin concentrations than NT heifers 24 h AT. In conclusion, transportation increased cortisol secretion and was correlated with increased metabolic responses and up‐regulation of peripheral innate immune cells in dairy heifers.     

Ultrastructure of the tubular glands in the isthmus region of the oviduct in laying and natural moulting commercial egg‐type chickens

The study investigated the ultrastructural characteristics of tubular gland and duct cells, as well as luminal gland cells in the isthmus region of the oviduct of laying and natural moulting hens. Tubular glands in laying birds were composed of type 1 and 2 cells. Based on the preponderance of each cell type, in relation to the location of a developing egg in the oviduct of the domestic fowl, these gland cells may represent different functional states of the same cell. The findings of the study on natural moulting birds suggest that autophagy is a process confined to the early stages of degeneration, while necrosis occurs in the terminal stages.     

High level expression of recombinated hepatocyte growth factor in human umbilical cord mesenchymal stem cells

AIM: To construct a lentiviral vector encoding human hepatocyte growth factor (hHGF) for transfection,and to observe the expression of hHGF in human umbilical cord mesenchymal stem cells.METHODS: pUC-SRα/hHGF was subcloned into the expression vector pWPI to construct recombinant pWPI-hHGF.hHGF was identified by gene sequence.Recombinant lentivirus was produced by pWPI-hHGF,pAX2 and pMD2G altogether transient transfection into 293T cells using calcium phosphate method.The pWPI-hHGF and the contructed pWPI-GFP were transfected into human umbilical cord mesenchymal stem cells by the Lipofectamin 2000.Through counting by the fluorescent microscope,the efficiency of the transfection was identified.The expressions of hHGF and GFP in human umbilical cord mesenchymal stem cells were also detected.The concentration of hHGF in cell culture medium was determined by enzyme linked immunosorbent assay (ELISA).RESULTS: DNA sequence showed that hHGF cDNA was correctly inserted into pWPI vector.The positive rate of hHGF transfecting 293T cells was 100 %.Bright green fluorescence in the transfected cells was observed under the fluorescent microscope after 24 h transfection with lentiviral plasmid pWPI-hHGF-GFP,and the transfection rate reached 80%.The difference was distinct between the pWPI-hHGF group and control group in the secretive level of hHGF by Western blotting and the ELISA (P<0.01).CONCLUSION: The recombinant pWPI-hHGF plasmid was successfully constructed and efficient,stable and ectopic expression of hHGF was accomplished in human umbilical cord mesenchymal stem cells.     

Effect of ensiling whole crop oat with lucerne in different ratios on fermentation quality,aerobic stability and in vitro digestibility on the Tibetan plateau

The objective of this study was to determine the effect of ensiling different ratios of whole crop oat to lucerne on fermentation quality, aerobic stability and in vitro digestibility of silage on the Tibetan plateau. Four experimental treatments were produced varying in the ratio of forages on a fresh matter (FM) basis: 1) 100% oat (control, dry matter (DM) content: 317 g/kg), 2) 90% oat + 10% lucerne (OL10, DM content: 316 g/kg), 3) 80% oat+ 20% lucerne (OL20, DM content: 317 g/kg) and 4) 70% oat+ 30% lucerne (OL30, DM content: 318 g/kg). All treatments were packed into laboratory‐scale silos and ensiled for 60 days and then subjected to an aerobic stability test for 15 days. Further, the four experimental treatments were incubated in vitro with buffered rumen fluid to study the nutrient digestibility. All silages were well preserved with low pH and NH₃‐N contents, and high lactic acid contents and V‐scores (evaluation of silage quality). Increasing the lucerne proportion increased (p < 0.05) crude protein (CP) content of silage, whereas neutral (NDF) and acid (ADF) detergent fibre contents were not affected. Under aerobic conditions, the control silage showed higher (p < 0.05) yeast counts (>10⁵ cfu/g FM) followed by OL10 silage, and OL10 silage improved aerobic stability for 74 h. OL20 and OL30 silages showed fewer (p < 0.05) yeasts (<10⁵ cfu/g FM) and markedly (p < 0.05) improved the aerobic stability (>360 h). After 48‐h incubation, OL30 silage increased (p < 0.05) in vitro dry matter digestibility (IVDMD) and neutral detergent fibre digestibility (IVNDFD) compared with the control silage. These results suggest that replacing oat with lucerne had no unfavourable effects on fermentation quality of silage, but improved CP content, aerobic stability IVDMD and IVNDFD. OL30 silage was the best among the three mixed silages.     

银杏幼胚离体培养再生植株的研究

 以佛手银杏幼胚为外植体, 研究了不同大小幼胚在不同培养条件下, 愈伤组织和胚状体的诱导发育情况。结果表明: 大于3 mm的幼胚, 在MK +NAA 1.0 mg·L ^{- 1} +BA 1.0 mg·L ^{- 1}培养基上胚状体诱导率最高, 达到53.6% , 最多的一块愈伤组织形成多达38个胚状体。暗培养不利于胚状体的发生。在MK培养基上添加10%椰汁对胚状体的生长发育有很好的促进作用, 有34.5%生长成苗。