山西瘦肉型猪SD-Ⅱ系繁殖性状的表型和遗传参数估测

本文对山西瘦肉型猪SD—Ⅱ系繁殖性状的表型参数和遗传参数进行了研究 ,结果如下 :(1)繁殖性状存在负的母体效应 ,表型变化不稳定 (呈亲代高子代低 ,亲代低子代高的趋势 ) ,不适宜用表型选择进行选择 ;(2 )总产仔数、活产仔数、初生窝重、初生个体平均重、泌乳力、断奶窝重、断奶个体平均重、断奶头数、总乳头数的遗传力分别为 0 2 30、 0 2 42、 0 2 19、 0 2 5 7、 0 184、 0 12 8、 0 40 8、 0 419、 0 5 0 2 ,与国内文献报道结果相近 ,而高于国外文献报道结果。 (3)繁殖性状间的遗传相关都比较强 ,断奶头数与大多数繁殖性状的遗传相关呈显著或极显著的正相关 ,因此应作为繁殖性状的主选性状之一     

杜洛克、大白、长白猪的生长和肉用性状杂交效果研究

为筛选优化杂交组合,进行了杜洛克（杜）、大白（大）、长白（长）品种间杂交试验,测定了不同品种组合的生长速度、饲料转化率、胴体和肉质性状及其杂种优势率。结果表明,杜洛克、父系大白猪作终端父本与长大杂母猪杂交,其后代的日增重、饲料转化率、屠宰率、胴体长、眼肌面积、后腿比例、瘦肉率及肉质等主要性状均无显著差异。     

离体研究脂肪型与瘦肉型猪脂肪组织代谢的年龄性变化

采用离体组织培养技术对不同经济类型猪种的脂肪合成代谢及分解代谢进行了比较研究。结果表明,脂肪的分解代谢在品种间差异不显著,而月龄间差异极显著,即随着年龄的增长,其脂解率明显下降。香猪利用#+14C-葡萄糖掺入总脂、脂肪酸、甘油及CO#-2的能力均显著高于长白猪,且脂肪酸的合成随年龄的增长而上升,甘油的合成随年龄的增长而下降。脂肪的合成代谢及分解代谢平衡的结果最终说明了脂肪随年龄增长而沉积增多的规律。     

猪传染性胸膜肺炎HT株的分离,鉴定与定型试验

近年来从山东省等地曾发生过猪传染性胸膜肺炎的一些猪场,分离并获得了ＡＰＰ菌株１８株。１９９８年又从青岛地区发病猪场分离到ＡＰＰ菌ＨＴ株,经鉴定确认为ＡＰＰ８型     

猪乳中IgG和有关生长因子的动态变化

选择８头３～４胎,产仔数９～１３头的健康内蒙黑猪（大白猪×内蒙黑猪）,对其分娩后２８ｄ泌乳期内初乳和常乳中的胰岛素（ｌｎｓ）、上皮生长因子（ＥＧＦ）、皮质醇（Ｃｏｒｔ）、ＩｇＧ和总蛋白（ＴＰ）进行了动态分析。结果表明,母猪刚分娩时其初乳中Ｉｎｓ、ＥＧＦ、Ｃｏｒｔ、ＩｇＧ、ＴＰ含量与常乳比较都很高（ｐ＜０．０５）,但是分娩后２４ｈ,初乳中这些成分除Ｉｎｓ外均急剧下降（ｐ＜０．０５）,并且到分娩后的７ｄ,猪乳中的上述成分接近常乳水平（ｐ＞０．０５）。     

猪血综合开发利用的研究

笔者设计了能够同时利用猪血各主要组分制备或提取特异性抗动物疾病γ－球蛋白、干扰素、血红素和ＳＯＤ的技术路线。以６头肥育猪（平均体重１１２ｋｇ）为试验材料,分别收集全血（１５１７ｍｌ／头）。试验结果表明,采用这一技术路线,可从１０００ｍｌ猪血制备或提取２．２５ｇ特异性抗动物疾病γ－球蛋白液,９．２３ｇ白细胞干扰素、３１２６ｍｌ血红素和１５．６ｍｇＳＯＤ。     

Prediction of protein and amino acid composition and digestibility in individual feedstuffs and mixed diets for pigs using near-infrared spectroscopy

Knowledge of the amounts and digestibility of amino acids in pig feedstuffs is essential for calculating the appropriate inclusion level in a complete diet. Wet chemical analysis and in vivo digestibility trials are time-consuming and costly and cannot be used for routine assessment. Near-infrared spectroscopy (NIRS) offers a rapid, cost effective and environmentally friendly method for evaluating feedstuffs. Calibrations models were developed using NIRS to predict the content of crude protein and 18 amino acids from a wide range of feedstuffs used in pig production (n = 607). The samples ranged from single feed ingredients (containing amino acids from 0.3 to 129.8 g/kg of dry matter) to feed mixtures (containing amino acids from 1.2 to 53.2 g/kg of dry matter). The predictive ability of the calibrations was tested with an independent dataset (n = 150) and with cross-validation. Furthermore, we compare these calibrations with calibrations developed on more narrowly defined groups of samples and with predictions from regression analysis of crude protein. The models were able to predict the concentrations of crude protein and 18 amino acids with good levels of precision and high coefficients of determination for calibration (RSQ ^CAL) from 0.91 to 0.99 and validation (RSQ^VAL) from 0.87 to 0.97. Calibration models were able to predict all amino acids except tryptophan and valine with greater accuracy than those from protein regression. We also developed calibration models to predict the apparent ileal and total tract digestibility of protein and amino acids. With the exception of tryptophan, RSQ values (>0.7) and standard error of cross validation (SECV) values (<5%) were obtained for the digestibility of most of the amino acids. In conclusion, NIRS can be used to predict crude protein and amino acid concentrations from a wide range of single ingredients and feed mixtures used for pig diets without separate models for each feedstuff. The digestibility of protein and amino acids can be predicted with an acceptable accuracy to be useful in formulating pig diets.     

Life cycle assessment of high- and low-profitability commodity and deep-bedded niche swine production systems in the Upper Midwestern United States

We used ISO-compliant life cycle assessment to evaluate the comparative environmental performance of high- and low-profitability commodity and deep-bedded niche swine production systems in the Upper Midwestern United States. Specifically, we evaluated the contributions of feed production, in-barn energy use, manure management, and piglet production to farm-gate life cycle energy use, ecological footprint, and greenhouse gas (GHG) and eutrophying emissions per animal produced and per live-weight kg. We found that commodity systems generally outperform deep-bedded niche systems for these criteria, but that significant overlap occurs in the range of impacts characteristic of high- and low-profitability production between systems. Given the non-optimized status of current deep-bedded niche relative to commodity production, we suggest that optimizing niche systems through improvements in feed and sow herd efficiency holds significant environmental performance improvement potential. Drivers of impacts differed between commodity and deep-bedded niche systems. Feed production was the key consideration in both, but proportionally more important in niche production due to lower feed use efficiencies. Liquid manure management in commodity production strongly influenced GHG emissions, whereas solid manure management increased eutrophication potential due to outdoor storage in deep-bedded niche production. We further observe an interesting but highly imperfect relationship between economic and environmental performance measures, where profitability tracks well with resource (in particular, feed) throughput, but only indirectly with emissions intensity.     

猪瘟病毒检测和猪瘟疫苗研究进展

猪瘟（Classical Swine Fever，CSF）是由猪瘟病毒（Classical Swine Fever Virus，CSFV）引起的高度 传染性、致死性疾病，是公认对养猪业危害最严重的病毒性疾病之一。自 1810 年首次报告 CSF 疫情至今，CSF 给世界养猪业造成了重大经济损失，持续威胁着全球猪肉生产和人类的食品安全。世界动物卫生组织将 CSF 列 为最重要的法定报告传染病之一，在我国被列为一类传染病。现阶段 CSF 临床表现形式复杂多变，有死亡率很 高的急性型或死亡率变化不定的亚急性型、慢性型、隐性型及持续感染型等，且常与多种疫病混合感染。目前， 疫苗免疫接种仍然是全球大多数国家特别是发展中国家防控 CSF 的主要手段， CSFV 抗原 / 抗体试验室诊断和临 床检测技术的开发和应用对于 CSF 防控也起到非常重要的作用。随着生物技术的快速发展，更多的 CSFV 抗原 / 抗体检测技术和新型疫苗被开发和批准使用。综述 CSFV 抗原和抗体检测技术、CSFV 减毒活疫苗和亚单位疫苗、 载体疫苗等新型疫苗开发进展等，以期为更好地防控 CSF 提供参考。     

基于免疫信息学方法设计针对猪急性腹泻综合征冠状病毒S、M及E蛋白的多表位疫苗

【目的】 设计针对猪急性腹泻综合征冠状病毒（Swine acute diarrhea syndrome coronavirus，SADS-CoV） S、M及E蛋白的多表位疫苗。【方法】 本研究选用IEDB预测SADS-CoV S、M及E蛋白T淋巴细胞主要组织相容性复合体Ⅰ（MHCⅠ）类分子结合表位；用NetMHCIIpan 4.0 Serve预测T淋巴细胞MHCⅡ类分子结合表位；用Immunomedicine Group、IEDB预测B淋巴细胞表位。将各个服务器预测结果筛选出重叠表位区域作为优势表位，运用IEDB、AllerTOP v 2.0 Servers筛选出高保守性、非致敏性的优势表位区域，通过柔性linker串联成多表位疫苗。对构建的多表位疫苗进行抗原性、理化性质、N-糖基化位点、二级结构和三级结构预测。使用分子对接评估多表位疫苗与免疫受体的结合能力，最后进行基因克隆。【结果】 经筛选后的高保守性、非致敏性优势表位构建的多表位疫苗相对分子质量为35.30 ku，为稳定亲水蛋白，具有良好的抗原性，存在1个N-糖基化位点，在二级结构中α-螺旋、β-折叠、无规则卷曲和β-转角分别占22.11%、20.35%、50.88%和6.67%。三级结构Ramachandran作图显示优势区域中含有残基数占到90.00%，进行细化后优势区域的残基数增加到91.92%，三级结构突出表位作图也证明多表位疫苗具有良好的免疫原性，分子对接表明多表位疫苗与TLR3具有高亲和力。经密码子优化、反向翻译和基因克隆确保设计的多表位疫苗在大肠杆菌K12表达系统中高效、稳定的表达。【结论】 构建的多表位疫苗抗原可有效表达并可能诱导强烈的T细胞和B细胞免疫应答。本研究为SADS-CoV多表位疫苗的设计提供了一种新的方法，为SADS-CoV多表位疫苗的研发提供了理论依据及数据支持。