鸡传染性法氏囊病双抗体夹心Dot—ELISA诊断法的建立及应用

以醋酸纤维素膜作为固相载体，辣根过氧化物酶标记鸡抗传染性法氏囊病病毒抗体，饱和二氨基联苯胺为底物显色，建立了鸡传染性法氏囊病双抗体夹心Ｄｏｔ－ＥＬＩＳＡ诊断法，经方阵实验确定最佳反应条件为：ＩｇＧ的包被液为０．０５ｍｏｌ／Ｌ（ＰＨ９．６）碳酸盐缓冲液，包被浓度为１、５０；酶标抗体的工作浓度为１；１００；洗涤液为含０．０５％吐温－８０的０．０２ｍｏｌ／Ｌ（ＰＨ７．４）磷酸盐缓冲液；封闭液为含０．２％     

ABC—Dot—ELISA检测鸡传染性支气管炎病毒

建立了ＡＢＣ－Ｄｏｔ－ＥＬＩＳＡ检测鸡传染性支气管炎病毒（ＩＢＶ）的方法,其最佳反应条件是：包被液为０．０５ｍｏｌ／ＬｐＨ９．６的碳酸钠－碳酸氢钠缓冲液（ＣＢＳ）,免疫ＩＢＶ ＩｇＧ的最佳工作浓度为１：８０;抗原的最佳浓度为１：８００;封闭剂选用０．０１ｍｏｌ／Ｌ ｐＨ７．４含３０ｍＬ／Ｌ白明胶的ＰＢＳ,Ｂ－ＡｇＧ和ＡＢＣ－ＨＥＰ的最佳工作浓度为１：２００。用ＡＢＣ－ＨＥＰ的最佳工作浓度为１：２０     

用ELISA检测山羊关节炎脑炎病毒抗体

以差速离心，结合ＳＤＳ处理制备ＥＬＩＳＡ抗原，用含０．０２％ＮａＮ３的碳酸盐缓冲液作抗原包被液，不加任何封闭剂，待测血清以含５％犊牛血清和０．０５％Ｔｗｅｅｎ－２０稀释，检测９２２份山羊血清的ＣＡＥ抗体，并与免疫扩散试验（ＡＧＩＤ）比较，提高检出率约一倍并减少漏检     

对流免疫电泳检测鸡肺炎克雷伯氏菌抗原的研究

用对流免疫电泳检测鸡肺炎克雷伯氏菌抗原，结果表明，该法敏感，特异，快速，重复性好，且可用１％球脂为载体，０．０５ＭｐＨ８．６巴比妥液为电泳缓冲液。     

鸡传染性法氏囊病双抗体夹心Dot─ELISA诊断法的建立及应用

以醋酸纤维素膜作为固相载体，辣根过氧化物酶标记鸡抗传染性法氏囊病病毒抗体（ＩＢＤ—ＩｇＧ），饱和二氨基联苯胺为底物显色，建立了鸡传染性法氏囊病双抗体夹心Ｄｏｔ—ＥＬＩＳＡ诊断法。经方阵实验确定最佳反应条件为：ＩｇＧ的包被液为０．０５ｍｏｌ／Ｌ（ｐＨ９．６）碳酸盐缓冲液，包被浓度为１：５０；酶标抗体的工作浓度为１：１００；洗涤液为含０．０５％吐温—８０的０．０２ｍｏｌ／Ｌ（ｐＨ７．４）磷酸盐缓冲液；封闭液为含０．２％明胶的洗涤液；封闭时间、抗原及酶标抗体的作用时间均为３７℃３０ｍｉｎ。应用本方法和琼扩试验同步检测２０份已知阳性病料、１２０份待检病料和胚毒尿囊液、１０份正常鸡样品，结果表明，Ｄｏｔ—ＥＬＩＳＡ阳性率为９０％，而琼扩试验为４０％；凡琼扩试验阳性者，Ｄｏｔ—ＥＬＩＳＡ均呈强阳性，而在Ｄｏｔ—ＥＬＩＳＡ阳性样品中，只有４４％呈琼扩试验阳性，Ｄｏｔ—ＥＬＩＳＡ的敏感度为琼扩试验的１００倍。     

玉米芯混菌两步发酵生产单细胞蛋白及高蛋白饲料

１材料与方法１．１菌种康宁木霉（Ｔｒｉｃｈｏｄｅｒｍａ　ｋｏｎｉｎｇｉｉ）、黑曲霉（Ａｓｐｓｒｇｉｌｌｕｓｎｉｇｅｒ　Ｎｏ．０１）和ＣａｎｄｉｄａｂｏｉｄｉｎｉｉＮｏ．２２０１诱变菌株Ｙ－１０８，均由四川大学生化室提供。１．２玉米芯粉玉米芯自然晾干，粉碎过２０目筛。１．３种子培养基察氏培养基，土豆培养基，Ｙ－１０８种子培养基：ＫＨ２ＰＯ４０．１ｇ、Ｋ２ＨＰＯ４０．１ｇ、Ｍｇ－ＳＯ４·７Ｈ２Ｏ０．０５ｇ、玉米浆６ｍＬ、甲醇１ｍＬ、水解液９３ｍＬ，用ＮａＯＨ溶液调至ｐＨ５．４。１．４试验方法将玉米芯…     

偏重亚硫酸钠钝化生豆粕胰蛋白酶抑制因子的研究

试验用不同浓度的Ｎａ２Ｓ２Ｏ５处理生豆粕，进行适宜水平研究。结果表明，当生豆粕ＴＩＡ和ＵＡ分别为２９．７２酶活单位和１．９５△ｐＨ时，分别用０．３％、０．４％、０．５％和０．６％ＮａＳ２Ｏ５处理ＲＳＢＭ，ＴＩＡ依次降低了５１．８％、５５．９６％、５９．８３％和５２．０５％，均极显著地低于ＲＳＢＭ（Ｐ＜０．０１）。０．３％Ｎａ２Ｓ２Ｏ５对ＵＡ无影响，其它处理ＵＡ提高约０．０６△ｐＨ。     

维生素B_（12）注射液解冻牛的冻精试验

用ＶＢ１２注射液解冻牛的冻精与用０．９％氯化钠溶液、复方氯化钠溶液和２．９％柠檬酸钠溶液解冻牛的冻精进行比较，精子活力提高１６．２３％（Ｐ＜０．０１）、１５．４３％（Ｐ＜０．０１）和１２．６７％（Ｐ＜０．０５）；顶体完整率提高１４．１２％（Ｐ＜０．０１）、１３．０３％（Ｐ＜０．０１）和１１．０７％（Ｐ＜０．０５）；而精子畸形率和精清中ＧＯＴ活性均明显地降低（Ｐ＜０．０５）；精子存活时间延长。试验结果表明，用ＶＢ１２注射液解冻牛的冻精对精子形态结构有保护作用．是一种较理想的解冻液。     

FMDV在BHK21细胞扩增后FMDV 140 S抗原的测定

本文报告了用蔗糖密度梯度离心和光密度分析相结合口蹄疫病毒（ＦＭＤＶ）在单层ＢＨＫ２１细胞中扩增后，其中ＦＭＤＶ １４０ Ｓ抗原浓度，并同时分析了经ＢＥＩ（二乙烯亚胺）灭活后，这种抗原含量的改变。结果表明，Ｏ型ＦＭＤＶ在单层ＢＨＫ２１细胞中增殖后，其ＦＭＤＶ １４０ Ｓ抗原浓度降至０．９μｇ／ｍｌ。     

山羊传染性胸膜肺炎氢氧化铝菌苗用铝胶配制中的几个问题

制造山羊传染性胸膜肺炎苗所使用铝胶即１／５Ｍ磷酸盐缓冲液铝胶，简称山传铝胶。根据我厂现用《操作细则》（１９８４年版）山传铝胶是用５份铝胶，４份１／５Ｍ磷酸盐缓冲液配制而成。为使山传铝胶ｐＨ达８．０～８．４，１／５Ｍ磷酸盐缓冲液中ＫＨ２ＰＯ４Ｎａ２ＨＰ...     

添加乳酸菌和发酵底物对桑叶青贮发酵品质的影响

为开发桑叶作为非常规饲料资源,本试验探讨了添加乳酸菌、葡萄糖或糖蜜对桑叶青贮发酵品质的影响,试验设对照组(C)、乳酸菌组(P)、葡萄糖组(G)、糖蜜组(M)、乳酸菌+葡萄糖组(P+G)、乳酸菌+糖蜜组(P+M),青贮后第7,14,30和60天开窖取样分析桑叶青贮饲料发酵品质。结果表明,添加乳酸菌加速了桑叶青贮过程中乳酸发酵,青贮第7天P,P+G和P+M组乳酸含量已达到C组的6倍以上,pH值降至4.30以下,其中P+G和P+M在青贮结束时降至4.0左右。补充发酵底物并未有效改善桑叶青贮发酵品质,C、G和M组pH值在青贮前30 d始终保持在5.85以上,青贮60 d时C组为5.96,G和M组分别下降至5.35和5.24,显著(P<0.05)高于P组。整个青贮过程中P组显示最高的乙酸含量,始终显著(P<0.05)高于C、G和M组,青贮7 d后开始显著(P<0.05)高于P+G和P+M组。青贮第7天P组氨态氮/总氮显著(P<0.05)低于对照组,之后各组氨态氮/总氮均随青贮时间的延长逐渐上升,其中P、P+G和P+M组氨态氮/总氮显著(P<0.05)低于C、G或M组直至青贮结束。本试验结论认为单独添加乳酸菌明显提高了桑叶青贮发酵品质,而组合添加并未进一步得到大的改善。     

添加剂对西藏混合青贮发酵品质和有氧稳定性的影响

为评价添加糖蜜、山梨酸钾和山梨酸钾+糖蜜对西藏地区燕麦(Avena sativa)和紫花苜蓿(Medicago sativa)(7:3)混合青贮发酵品质和有氧稳定性的影响,设对照组(C),4%糖蜜组(M),0.15%山梨酸钾组(S)和山梨酸钾+糖蜜(S+M)4个处理,青贮后第30,45,60 d开窖取样,测定青贮饲料的发酵品质,其他青贮窖在发酵60 d后全部打开,暴露于空气中5,10,15 d后取样分析其有氧稳定性.结果表明:与对照组相比,M组及S+M组pH显著降低,乳酸含量显著升高(P<0.05),有效地改善了混合青贮发酵品质,S组改善效果不显著.有氧暴露过程中,对照组和M组pH值迅速升高,乳酸含量显著减少(P<0.05),S组和S+M组的pH值、乳酸、水溶性碳水化合物等含量相对稳定.表明S+M组既能提高燕麦和紫花苜蓿混合青贮发酵品质,又能改善有氧稳定性.     

青贮菌剂在苜蓿裹包青贮中的应用效果

在苜蓿裹包青贮中添加3种不同青贮菌剂JD6、MMD3、X3Q2,分析青贮苜蓿的营养品质,微生物数量以及瘤胃降解率的变化,以研究3种青贮菌剂在裹包青贮条件下对苜蓿青贮的影响。结果表明,青贮5个月后,添加青贮菌剂可以显著降低pH值(P<0.05)、NH3/TN值(P<0.05),减少丁酸含量(P<0.01),有利于保存青贮物的营养成分,提高青贮品质。添加青贮菌剂对青贮物的NDF、ADF含量没有影响,对青贮产物干物质和NDF的瘤胃降解率没有影响。添加青贮菌剂可以提高青贮产物中乙酸含量(P<0.05),减少酵母菌和霉菌数量(P<0.05)。3种青贮菌剂在苜蓿裹包青贮试验中,有利于抑制有害微生物,保存苜蓿营养成分,提高苜蓿青贮品质和有氧稳定性。     

添加不同水平莫能霉素对奶牛瘤胃内日粮营养物质发酵及血液生化指标的影响

[目的]该试验旨在探讨日粮中添加不同水平莫能霉素,对奶牛瘤胃内发酵、日粮营养物质降解率及奶牛血液生化指标影响。[方法]试验选取3头安装永久性瘤胃瘘管奶牛,设计采用3×3拉丁方试验设计。试验分为三组,MⅠ组为基础日粮;MⅡ组为基础日粮添加31.5mg/kg DM莫能霉素;MⅢ组基础日粮添加46.5 mg/kg DM莫能霉素。[结果]莫能霉素添加组pH值均高于对照组（P〉0.05）;添加46.5 mg/kg DM的莫能霉素后氨态氮浓度显著低于对照组（P〈0.05）;日粮中添加46.5 mg/kg DM的莫能霉素后瘤胃内乙酸发酵量显著低于对照组（P〈0.05）;日粮中添加31.5 mg/kg DM莫能霉素后丙酸发酵量高于对照组（P〉0.05）,且丙酸摩尔比例显著高于对照组（P〈0.05）;日粮DM、CP和NDF在瘤胃内有效降解率随莫能霉素添加量的增加而降低,添加组奶牛血液中的尿素氮,血浆中血糖及乳酸浓度,各组间差异不显著（P〉0.05）。[结论]日粮中添加莫能霉素可以提高牛瘤胃中的pH值,降低氨态氮浓度,显著提高丙酸摩尔比例,降低丙酸、乙酸比值,但减缓了粗蛋白的降解速度,一定程度上提高血液中尿素氮和血糖浓度。     

Chemical properties of cow and beef muscles: benchmarking the differences and similarities

The objective of this study was to identify muscles from cow populations that are equivalent or may possibly be made equivalent to muscles from A-maturity, Select-grade cattle in terms of chemical, compositional, and color characteristics. Objective color, expressible moisture, proximate composition, pH, heme iron concentration, and total collagen content were determined for 9 muscles (M. gluteus medius, M. infraspinatus, M. longissimus dorsi, M. psoas major, M. rectus femoris, M. tensor fascia latae, M. teres major, M. triceps brachii lateral-head, and M. triceps brachii long-head) from 15 cattle from each of 5 commercially identified populations [fed beef cows (B-F), non-fed beef cows (B-NF), fed dairy cows (D-F), non-fed dairy cows (D-NF), and A-maturity, Select-grade cattle (SEL)]. Muscles from B-F and B-NF populations were more similar to the SEL than were the D-F and D-NF. There were 2 muscles, the M. infraspinatus and M. teres major, from the population of B-F that were similar, physically and chemically, to SEL in most traits. The majority of the 9 muscles from the cows did not differ (P < 0.05) from SEL for percentage expressible moisture, proximate composition, and total collagen content. However, notable differences in pH, objective color L*, total pigment content, and heme iron content existed between cow populations and SEL. The muscles from SEL had significantly (P < 0.05) lower total pigment and heme iron concentrations. These differences likely relate to the visual appearance of muscles from the different populations of cattle. Two of the 9 muscles studied were similar among cow populations and A-maturity, Select-grade beef.     

香蕉茎叶与柱花草混贮饲料的品质

为分析香蕉(Musa paradisiaca)茎叶与柱花草(Stylosanthes guianensis)混合青贮发酵品质,本研究选择新鲜香蕉茎叶和柱花草进行香蕉茎叶单独青贮(以下简称单贮)、柱花草单贮、75%香蕉茎叶+25%柱花草混合青贮(以下简称混贮)及50%香蕉茎叶+50%柱花草混贮,青贮5周后,对青贮饲料进行感官评定和品质检测,探讨香蕉茎叶与柱花草的适宜混合比例。感官评定结果表明,香蕉茎叶单贮感官评定最优,柱花草单贮感官评分等级最低,二者混贮评分居中,并且随着香蕉茎叶比例的降低青贮饲料感官品质下降。实验室指标分析表明,香蕉茎叶单贮时pH值最低,随着柱花草比例的增加,青贮饲料pH升高(P0.01),而乳酸菌菌落数增加(P0.05);柱花草单贮,乙酸含量最低,乳酸和丁酸含量各处理组间差异不显著(P0.05),且丁酸含量很低,对青贮品质影响不大;75%香蕉茎叶与25%柱花草混贮提高了青贮饲料乳酸菌菌落数和乳酸、乙酸的含量。随着柱花草比例的增加,混贮饲料初水分含量降低,粗纤维和粗蛋白的含量显著上升(P0.05),可溶性碳水化合物含量下降(P0.05)。综合青贮饲料品质感官评定和实验室检测结果,香蕉茎叶与柱花草混贮可降低香蕉茎叶初水分含量,提高柱花草可溶性碳水化合物水平,改善青贮饲料的发酵品质,当75%香蕉茎叶与25%柱花草混贮时,青贮效果最佳。     

In vitro and in vivo evaluation of lysozyme extracts of virulent Mycobacterium bovis in guinea pigs and calves

Extracts of Mycobacterium bovis ATCC 19210 were prepared from cells following treatment with acetone 3 times, ethyl alcohol-ether 3 times (1:1, v/v), and chloroform 3 times. Cells were dried and suspended in 0.05M Tris-HCl (pH 7.5) containing lysozyme (1 mg/50 mg of dried cells). One aliquot of the lysozyme extract was filter-sterilized and 1 aliquot of the lysozyme extract was autoclaved. Delayed-type hypersensitivity responses elicited in sensitized guinea pigs, using the filter-sterilized lysozyme extract, were significantly greater than responses elicited using the autoclaved lysozyme extract (P less than 0.01). The filter-sterilized lysozyme extract and a purified protein derivative (PPD) of M bovis, at equal protein concentrations, elicited comparable delayed-type hypersensitivity responses in sensitized guinea pigs. Significant differences were not detected between the mean enzyme-linked immunosorbent assay (ELISA) values on sera collected from calves before exposure to M bovis, using each of the lysozyme extracts or the M bovis PPD (P greater than 0.05). Significant differences were detected when ELISA values obtained using each of the antigens on post-exposure serum were compared with ELISA values on serum collected from calves before exposure to M bovis (P less than 0.01). Differences were not detected in mean ELISA values on sera from cattle collected 12 months after exposure to M bovis, using each of the lysozyme extracts or M bovis PPD (P greater than 0.05); however, 8 of 8 calves were identified as positive on ELISA, using the filter-sterilized lysozyme extract, 7 of 8 calves were positive, using M bovis PPD, and 7 of 8 calves were positive, using the autoclaved lysozyme extract.     

添加乳酸菌、糖蜜和无机酸对羊草青贮饲料发酵品质及体外干物质消失率的影响

本试验旨在探讨添加乳酸菌、糖蜜和无机酸对羊草青贮饲料发酵品质及体外干物质消失率的影响。采用单因子完全随机设计,在羊草青贮时设置如下5个处理:1)无添加(对照组,C组);2)添加0.00025%乳酸菌(LAB组);3)添加4%糖蜜(M组);4)添加4%无机酸(IA组);5)添加0.00025%乳酸菌+4%糖蜜(LAB+M组)。各青贮添加剂的添加量均为鲜重基础,每个处理设置3个重复,青贮120 d后取样分析羊草青贮饲料的发酵品质及体外干物质消失率。结果显示:所有组发酵品质均优良,且均未检测出丁酸、大肠杆菌、霉菌和梭菌;与对照组相比,各添加剂组pH显著降低(P<0.05);LAB+M组的乳酸含量显著高于其他各组(P<0.05);与对照组相比,所有添加剂组的氨态氮/总氮均有不同程度的下降;M组和LAB+M组的干物质含量显著高于对照组(P<0.05);IA组的粗蛋白质含量显著高于其他各组(P<0.05);LAB+M组的中性洗涤纤维含量显著低于其他各组(P<0.05);LAB+M组的产气量最高,显著高于M组(P<0.05);LAB+M组的体外干物质消失率显著高于对照组和LAB组(P<0.05)。综上所述,本试验所使用的青贮添加剂均能在不同程度上改善羊草青贮饲料的发酵品质和体外干物质消失率,综合考虑,以同时添加乳酸菌和糖蜜的效果最好。     

Effect of cyclodextrin diallyl maleate on methane production, ruminal fermentation and microbes in vitro and in vivo

Effects of β‐cyclodextrin diallyl maleate (CD‐M) on methane production, ruminal fermentation and digestibility were studied both in vitro and in vivo. In in vitro study, diluted ruminal fluid (30 mL) was incubated anaerobically at 38°C for 6 and 24 h with or without CD‐M using hay plus concentrate (1.5:1) as a substrate. The CD‐M was added at different concentrations (0, 1.25, 2.5, 5.0 and 7.5 g/L). The pH of the medium and numbers of protozoa were not affected by the addition of CD‐M. Total volatile fatty acids were increased and ammonia‐N was decreased, molar proportion of acetate was decreased and propionate was increased (P < 0.05) by CD‐M. Methane was inhibited (P < 0.05) by 14–76%. The effect of CD‐M on methane production and ruminal fermentation was further investigated in vivo using four Holstein steers in a cross‐over design. The steers were fed Sudangrass hay and concentrate mixture (1.5:1) with or without CD‐M (2% of feed dry matter) as a supplement. Ruminal proportion of acetate tended to decrease and that of propionate was increased (P < 0.05) 2 h after CD‐M dosing. Total viable counts, cellulolytic, sulfate reducing, acetogenic bacteria and protozoa were unaffected while methanogenic bacteria were decreased (P < 0.05) by CD‐M. The plasma concentration of glucose was increased, whereas that of urea‐N was decreased (P < 0.05). Methane was inhibited (P < 0.05) from 36.4 to 30.1 L/kg dry matter intake by the addition of CD‐M. Apparent digestibilities of dry matter and neutral detergent fiber were not affected while that of crude protein was increased (P < 0.05) in the medicated steers. These data suggested that dietary supplementation of CD‐M decreased methane production and improved nutrient use.     

饲粮中添加过瘤胃蛋氨酸、过瘤胃赖氨酸对荷斯坦奶公牛肉用生产性能和肉品质的影响

本试验旨在研究在饲粮中添加过瘤胃蛋氨酸(RPMet)、过瘤胃赖氨酸(RPLys)对荷斯坦奶公牛肉用生产性能和肉品质的影响。采用完全随机试验设计,选择25头12月龄左右、体重相近的健康荷斯坦奶公牛,随机分为5组,每组5个重复,每个重复1头。对照组饲喂基础饲粮(牧场实用饲粮);其余4个试验组分别在基础饲粮中添加RPMet 15 g/d(RPM组)、RPLys30 g/d(RPL组)、RPLys 30 g/d+RPM et 15 g/d(RPL+M组)和RPLys 30 g/d+RPM et 15 g/d(同时基础饲粮粗蛋白质水平降低1.71%)[RPL+M(L)组]。预试期10 d,正试期150 d。结果表明:1)RPL+M组和RPL+M(L)组试验牛末重、平均日增重均显著高于对照组(P0.05),料重比显著低于对照组(P0.05),但这2组间差异不显著(P0.05);RPL+M(L)组养殖效益最高,为7.67元/(d·头),且高出RPL+M组0.32元/(d·头)。2)与对照组相比,饲粮中添加RPM et、RPLys对荷斯坦奶公牛净肉率无显著影响(P0.05);RPM组、RPL组、RPL+M组和RPL+M(L)组宰前活重显著增加(P0.05),且以RPL+M组最高,但RPL+M组与RPL+M(L)组无显著差异(P0.05);RPL组屠宰率显著升高(P0.05);各试验组胴体产肉率和肉骨比均显著增加(P0.05),但试验组间差异不显著(P0.05)。3)饲粮中添加RPMet、RPLys对眼肌面积、剪切力、熟肉率、大理石花纹等级、p H和肉色等级均无显著影响(P0.05)。4)饲粮中添加RPMet、RPLys对肌肉脂肪酸组成亦无显著影响(P0.05)。综上所述,在饲粮中添加RPM et、RPLys可保持奶公牛同等的肉品质和肌肉脂肪酸含量,并在一定程度上提高奶公牛肉用生产性能;且添加RPMet和RPLys可替代部分蛋白质饲料,增加养殖效益。