家蚕3龄入棚饲育技术探讨

随着蚕桑生产的发展，蚕业规模经营的比重越来越高，蚕室紧缺的矛盾日益突出。为解决这一矛盾，大棚养蚕已成为蚕桑生产中推广应用的一项新技术。现行塑料大棚育一般是4龄入棚，为了更好适应规模经营的需要，我们于2003年秋蚕期尝试家蚕3龄入棚落地饲养，试验获得成功。2004年我们将扩大推广面，对家蚕3     

猪营养与肠道健康

肠道不仅在消化吸收营养物质过程中发挥着重要作用,而且是机体的重要免疫屏障,肠道健康水平决定着动物的健康状况。肠道结构的完整性和功能的正常发挥均需要通过获取各种营养物质来维持,因此,日粮中各种营养成分对肠道健康十分重要。本文综述了近年关于猪肠道营养成分对肠道健康影响的研究进展。     

警犬技术工作执法资格等级考试考核制度研究

2008年开始,公安部警犬技术学校希望通过警犬技术工作执法资格等级考试考核制度的研究,以进一步促进警犬技术工作的正规化、规范化、标准化.     

Identification of antigenic epitopes of the SapA protein of Campylobacter fetus using a phage display peptide library

In this study, we immunized mice with prokaryotically expressed recombinant surface layer protein, SapA, of Campylobacter fetus, generated hybridomas secreting mouse monoclonal antibodies (mAb) targeting SapA, and purified the mAb A2D5 from mouse ascites using saturated ammonium sulfate solution. The mAb A2D5, coated onto ELISA plates, was used to screen the phage random 12-peptide library through three rounds of panning. Following panning, 15 phage clones were randomly chosen and tested for reactivity with mAb A2D5 by indirect ELISA. Single-stranded DNA from positive clones was sequenced and compared with the sequence of SapA to predict the key epitope. ELISA and/or Western blot analyses further validated that synthetic peptides and recombinant peptide mimotopes all interact with mAb A2D5. Nine of ten positive phage clones identified by screening were sequenced successfully. Seven clones shared the same sequence HYDRHNYHWWHT; one had the sequence LSKNLPLTALGN; and the final one had the sequence SGMKEPELRSYS. These three sequences shared high homology with SapA J05577 in the region GNEKDFVTKIYSIALGNTSDVDGINYW, in which the underlined amino acids may serve as key residues in the epitope. ELISA and/or Western blot analyses showed that mAb A2D5 not only interacted with the four synthetic peptide mimotopes, but also with 14 prokaryotically expressed recombinant peptide mimotopes. The mimotopes identified in this study will aid future studies into the pathological processes and immune mechanisms of the SapA protein of C. fetus.     

Calcium homeostasis and its relationship to superoxide production in blood and milk neutrophils of lactating goats

Polymorphonuclear neutrophils (PMN), which comprise over 70% of the somatic cells in goat milk, are a major cellular component of innate immunity in the goat mammary gland. However, the function of milk PMNs is modified after diapedesis compared to PMNs in blood. As many aspects of PMN activity depend directly on intracellular Ca²⁺ concentration ((Ca²⁺)_i), the present study aimed to determine the changes in Ca²⁺ homeostasis of milk PMNs from lactating goats compared to autologous blood PMNs, and to examine the significance of these variations to the immuno-competency of milk PMNs. The intracellular Ca²⁺ store of freshly prepared milk cells was estimated from the elevation of (Ca²⁺)_i after ionomycin treatment, which was found to be significantly less than blood PMNs. Replenishment of the intracellular Ca²⁺ store in milk cells after intracellular Ca²⁺ depletion by Bapta-AM followed by spiking with 2.5 mM Ca²⁺ for 20 min was also compared to that of blood PMNs, showing that after depletion/spiking the intracellular Ca²⁺ store in milk cells was much less than blood PMNs. The production of superoxide anion (O₂^?) in vitro in response to (Ca²⁺)_i-dependent or (Ca²⁺)_i-independent modulators was used to evaluate the relevance of altered Ca²⁺ homeostasis on the immuno-competency of milk cells compared to blood PMNs. The results indicated that milk cells produced similarly low levels of O₂^? as blood PMNs when treated with ionomycin. However, the amount of O₂^? produced by milk cells in response to phorbol 12-myristate 13-acetate (PMA) stimulation, although greater than ionomycin treatment, was significantly less than that of blood PMNs. The capacity for O₂^? production by both cell types in response to PMA reverted to the resting state with use of the protein kinase C (PKC) inhibitor, staurosporine. In conclusion, the current study demonstrated an irreversible shortage of intracellular Ca²⁺ in the milk PMNs of lactating goats compared to blood PMNs. It also showed that preliminary O₂^–production, primed by ionomycin treatment, remained unchanged in milk PMNs, despite the shortage in intracellular Ca²⁺, but decreased O₂^? production capacity, mediated via the PKC pathway, in milk PMN. It is suggested that the defects in Ca²⁺ homeostasis in milk PMNs of lactating goats is partially attributable for the post-diapedesis functionality modifications.     

不同饲用燕麦品种生产性能的综合评价

基于熵权赋权法,运用灰色系统理论中的灰色关联度法对26个燕麦品种的生产性能进行综合评价,结果表明,生产性能综合表现较好的是初岛燕麦、青永久409、青永久709及青永久316;青永久18综合评价值最低,生产性能最差,其余品种生产性能表现一般。经逐步回归分析,发现其中的绿叶数、叶长、茎叶比、鲜干比、生长速度、叶面积指数、相对生长速率及生长天数8个指标对饲用燕麦生产性能贡献显著。     

短时高温处理对意大利蝗卵子发生期HSP70蛋白表达的影响

本研究采用免疫组织化学分析方法,测定了HSP70蛋白在意大利蝗卵子发生期的表达定位及33~42℃高温处理对其相对表达量的影响。结果表明,1)在卵黄发生前期,卵母细胞和滤泡细胞均表达HSP70蛋白,而在卵黄发生期和卵黄发生后期,HSP70蛋白阳性表达位于滤泡细胞;2)在33~42℃温度范围内,随着温度升高,意大利蝗卵子发生期HSP70蛋白相对表达量呈现先上升后下降的变化趋势;其中36℃处理组HSP70蛋白相对表达量最高,显著高于27℃对照组(P0.05);42℃处理组HSP70蛋白相对表达量最低,但与27℃对照组差异不显著(P0.05)。短时高温处理对意大利蝗卵子发生期HSP70蛋白相对表达量有显著影响,推测HSP70蛋白的表达在意大利蝗抵抗短时高温胁迫过程中具有重要作用。     

20个龙须草种质资源叶片解剖特征

主要采用扫描电子显微镜技术,对收集的20个龙须草(Eulaliopsis binata)种质资源叶片进行电镜扫描,结果表明,不同种质资源叶片形态中的叶长、叶宽、叶面积,以及叶解剖结构中的叶片表皮厚度、叶片厚度、叶片气孔密度、叶片气孔长、叶片气孔宽、叶片纤维细胞直径、胞壁厚度、腔径、腔壁比等均呈现出显著或极显著差异,以优选造纸材料中重要指标壁腔比进行聚类分析,可将供试龙须草种质资源造纸性能分为最优、较好、较差和最差4类。试验结果可为中国南方丘陵区龙须草种质资源良种选育和开发利用研究提供依据。     

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.     

寄生虫细胞因子免疫的研究进展（一）

寄生虫在入侵机体时必须具备逃避机体免疫,破坏宿主免疫屏障才能感染,这种入侵过程必然和宿主机体的免疫系统发生联系,不但使宿主的先天免疫细胞功能缺失,而且获得性免疫也受到抑制。寄生虫感染均不同程度地伴随免疫损伤,宿主在感染寄生虫后产生的免疫应答中,细胞因子作为免疫过程中的介质起到关键作用,主要是调节机体细胞免疫抗虫,保护机体不被感染,其中巨噬细胞是主要功能的承担者。本文将阐述细胞因子在寄生虫感染过程中所发挥的免疫作用,为解决寄生虫感染的防控问题奠定基础,同时为寄生虫的研究提供新的思路。