农艺措施对大豆籽粒蛋白质和脂肪含量的影响

探讨了栽培密度、撒可富专用肥、思德富多元长效肥等农艺措施对大豆籽粒蛋白质和脂肪含量的影响。结果表明 ,密度对蛋白质含量、脂肪含量和蛋白脂肪总含量的影响不大。在各种栽培密度中 ,品种九三 97- 6 0是在 30万株 /hm2 时籽粒的蛋白质含量、脂肪含量和蛋白脂肪总含量均达到最高值 ,而对于品种九三 96 - 12 7来说 ,是在 2 5万株 /hm2 时三者达到最高。并且 ,蛋白质含量、脂肪含量及蛋白脂肪总含量对栽培密度敏感程度因品种而异。撒可富专用肥和思德富多元长效肥均使蛋白质含量增加 ,使脂肪含量降低。施用撒可富专用肥后 ,蛋白脂肪总含量变化因处理而异。施用思德富后 ,蛋白脂肪总含量有所增加。     

钢筋混凝土框架—剪力墙结构非线性地震反应分析

The inelastic response of reinforced concrete plane frame-wall structures subjected to strong ground motions is studied from an analytical standpoint. In the analysis, the structure is idealized as the assemblage of prismatic members with two rigid zones     

陇西南塬区农业生产系统结构与效益研究

本研究通过对陇西南塬区农业生产系统的结构分析，确认该系统的特征为产业结构不合理（以种植业为主），种植业以粮食生产为主，复种指数低（１１１％）；养殖业中草食家畜比例低，饲养技术落后，良种率低；林果业效益低下；人口密度高，劳动力过剩，生产能源短缺等。通过系统分析提出了调控方针，该系统整体效益提高的关键是发展以草食家畜为核心的养殖业，种植业应及时调整结构，提高经济作物和饲料作物的比例，提高复种指数，林果     

振动胁迫对杨梅果实采后衰老生理的影响

振动胁迫促进杨梅果实的衰老，表现为促进膜诱性的增加和ＳＯＤ活性与精胺含量的下降。但在振动胁迫后的贮藏初期，果实多源精胺的合成明显增加，而乙烯产生量明显降低，这可能是杨梅果实抗振动胁迫的一种应激机制。而在振动胁迫后的贮藏后期，果实的精胺含量降低，腐胺积累较多，乙烯产生量较高，表明振动胁迫最终促进果实的全面衰老。     

Influence of dietary cobalt source and concentration on performance, vitamin B12 status, and ruminal and plasma metabolites in growing and finishing steers

Sixty Angus steers, averaging 274 kg, were used to evaluate the effects of Co source and concentration on performance, vitamin B12 status, and metabolic characteristics of steers. Treatments consisted of 0 (control, analyzed 0.04 mg Co/kg), 0.05, 0.10, and 1.0 mg of supplemental Co/kg of DM from CoCO3 or 0.05 and 0.10 mg of supplemental Co/kg of DM from Co propionate. Steers were individually fed a growing diet for 56 d followed by a high-concentrate finishing diet. Performance was not affected by Co supplementation during the growing phase. During the finishing phase, ADFI (DM basis) and ADG were higher (P < 0.05) for the entire finishing phase, and gain:feed was higher (P < 0.10) over the first 56 d for Co-supplemented steers. Steers supplemented with 0.10 mg Co/kg as Co propionate had higher (P < 0.05) ruminal propionate and lower (P < 0.05) acetate molar proportions than steers receiving 0.10 Co/kg as CoCO3 during the growing phase. Supplemental Co increased (P < 0.10) molar proportion of propionate during the finishing phase. Plasma vitamin B12 was higher (P < 0.05) in Co-supplemented steers by d 56 of the growing phase and remained higher (P < 0.10) throughout the study. Control steers had higher (P < 0.05) plasma methylmalonic acid on d 56 of the growing phase and on d 28, 56, and 112 of the finishing phase than steers receiving supplemental Co. Steers supplemented with Co had higher plasma glucose at d 56 (P < 0.01), 84 (P < 0.10), and 112 (P < 0.01) of the finishing phase. Steers supplemented with 0.10 mg Co/kg as Co propionate had higher plasma glucose than those receiving 0.10 mg Co/kg as CoCO3 at d 28 of the growing phase (P < 0.05) and d 28 of the finishing phase (P < 0.10). Final body weight and hot carcass weight were lower (P < 0.10) in steers receiving the control diet, whereas other carcass characteristics were not affected by dietary Co. Average daily gain and feed efficiency for the entire finishing phase did not differ among Co-supplemented steers. However, increasing supplemental Co above 0.05 mg/kg DM (total diet Co = 0.09 mg/kg) resulted in increased (P < 0.01) plasma (linear) and liver (quadratic) vitamin B12 concentrations and decreased (quadratic, P < 0.10) plasma methylmalonic acid concentrations toward the end of the finishing phase. These results suggest that finishing steers require approximately 0.15 mg Co/kg of DM. Vitamin B12 status was not affected by Co source; however, the two Co sources seemed to affect certain metabolites differently.     

猪传染性胃肠炎病毒分子生物学研究进展

猪传染性胃肠炎病毒(TGEV)基因组为不分段的单股正链RNA,其编码4种结构蛋白和3种非结构蛋白。TGEV S蛋白是基因工程研究的重点,近年来,S蛋白在大肠埃希菌、沙门菌、腺病毒等中得到了高效表达。将传染性胃肠炎病毒的基因组人工改造成为感染性cDNA的表达载体,此载体可在ORF3处插入外源基因,异源基因绿荧光蛋白可稳定、高效地表达。TGEV基因1和其他冠状病毒相比保守性很强,所以对TGEV聚合酶的研究,特别是其中保守酶的研究,对于抗TGEV及其他冠状病毒药物的研究有着重要的意义。     

雏鸭胸腺生长指标的动态观测及组织学观察

通过对1～49日龄雏鸭胸腺发育的组织学观察及胸腺重量、胸腺指数和外周血T淋巴细胞α-醋酸萘酯酶阳性率（ANAE^＋）的测定，研究了雏鸭胸腺的生长及组织发育规律。结果显示，胸腺重量随日龄增长逐渐增加；胸腺指数在28日龄时达最高；1～28日龄时外周血T淋巴细胞ANAE^＋上升幅度较大；21～28日龄时胸腺小叶数量增多，并显著增大；28日龄时皮质部主要为小淋巴细胞；胸腺小体有3种形态。表明，雏鸭在1～14日龄时胸腺生长较缓慢，21～28日龄时生长十分迅速，28日龄时胸腺中大部分T淋巴细胞已发育成熟，35～49日龄时胸腺发育已趋于稳定；胸腺小体是具有高度活性的结构，与清除退变上皮有关。     

高铜对雏鸡器官组织病理损害的研究

将420只1日龄艾维菌健雏，随机分为7组，分别饲以含铜量11mg／kg的基础日粮和含铜量分别为100、200、300、400、500和600mg／kg的6种高铜日粮6周，研究高铜对雏鸡的病理损害。结果显示，日粮含铜100和200mg／kg对雏鸡有促生长作用。日粮铜水平达300mg／kg以上时，对雏鸡器官组织造成不同程度的病理损伤，表现为肌胃角质层增厚呈黄褐色；肝呈浅黄色或深褐色，肝细胞脂肪变性；消化道上皮细胞变性坏死；免疫器官和肾、心脏、胰腺、大脑等器官的实质细胞肿胀；淋巴免疫器官体积缩小，淋巴细胞数量减少。超微结构观察发现，肝细胞胞浆和胞核内见有数量不等、大小不一的高电子密度的沉积物；凋亡的淋巴细胞染色质呈花瓣样、半月形或环形，聚集在核膜下。表明，肝、消化道和免疫器官是高铜损害的主要靶器官。     

不同生态区藏山羊的产绒性能研究

选择青藏高原四个不同的生态区,对藏山羊的产绒性能进行了研究,结果表明：西藏两个产区藏山羊的产绒量和绒的主要品质指标均高于四川两个产区,尤其是西藏阿里地区藏山羊的产绒量和绒的品质明显优于其他产区,四川茂县藏山羊的产绒量和绒的品质较差;同时,西藏两产区藏山羊的产绒量从年龄上看以４岁较高,从毛色上看以白色个体较高;四个不同生态区内藏山羊的产绒性能差异较大,越严酷的高寒生态条件,其产绒量越高,绒的品质越好。今后应根据不同的生态区按不同的生产方向对藏山羊这一宝贵的基因库资源进行开发利用。     

生长猪棉籽粕消化能的评定及估测模型研究

本试验通过采集我国棉花主产区棉籽粕样品,分析棉籽粕常规成分,测定其生长猪消化能(DE),建立棉籽粕常规成分与生长猪DE之间的关系。采用15%和20%替代比例的套算法,分别测定生长猪棉籽粕DE,探讨套算法中不同替代比例对DE的影响。试验选用体重[(37.2±1.8)kg]相近的"杜×长×大"三元杂交健康阉公猪18头,采用3个6×6拉丁方试验设计,全收粪法分别测定9个棉籽粕样品DE,并将棉籽粕常规成分与DE进行相关分析,建立回归方程,比较2个不同替代比例的套算法测定的DE。结果表明:本次试验所测定棉籽粕DE的加权平均值(风干基础,干物质90.41%)为9.94 MJ/kg;长江流域棉区平均值(风干基础,干物质89.72%)为9.96 MJ/kg;黄河流域棉区平均值(风干基础,干物质89.86%)为9.23 MJ/kg;西北内陆棉区平均值(风干基础,干物质91.30%)为10.61 MJ/kg。推荐DE预测模型(干物质基础):DE(MJ/kg)=-14.38+0.557×总能+0.320 95×粗蛋白质-0.012 68×中性洗涤纤维(R2=0.72)。套算法中的2个不同替代比例(15%和20%)对DE影响较小。