重组鸡白细胞介素-2对球虫感染雏鸡细胞免疫的影响

本实验旨在研究重组鸡白细胞介素－２对球虫感染雏鸡细胞免疫的影响。实验采用１４日龄伊莎蛋鸡２１０只，分为７组，其中一组为不感染对照组，三组为柔嫩艾美耳球虫感染组，卵囊感染剂量分别为１万／只、２万／只、５万／只，另外三组在感染卵囊１万／只、２万／只、５万／只的同时，肌注真核细胞表达的重组鸡白细胞介素－２ ０．４ｍｌ／只。感染后第０、４、６、９、１４、１８、２３、２８天剖杀取牌和盲肠扁桃体，分离淋巴细胞，分别用ＣｏｎＡ和ＰＨＡ刺激，采用ＮＩＴ比色法进行淋巴细胞转化试验，结果表明：在球虫感染后第４天（裂殖生殖阶段）和第６天（卵囊形成阶段），感染组脾和盲肠扁桃体淋巴细胞转化率均低于对照组，加重组鸡白细胞介素－２组脾和盲肠扁桃体淋巴细胞转化率高于感染组，相当或高于对照组水平。在感染后第９天和第１４天（恢复期）加重组鸡白细胞介素－２组脾淋巴细胞转化率高于对照组，加重组鸡白细胞介素－２组盲肠扁桃体淋巴细胞转化率相当于对照组。本实验结果说明：１．球虫感染可以抑制细胞免疫；２．加重组鸡白细胞介素－２可以克服球虫感染引起的免疫抑制。     

新城疫V4株弱毒变种的选育

应用有限稀释法通过ＳＰＦ鸡胚传代，从新城疫Ｖ２弱毒中克隆出一个变各，即２０代以后的继代毒，命名为新城疫Ｖ４克隆２０弱毒株，（ＮＤ－Ｖ４Ｃ２０）。毒以１０＾－１－１０＾１３×０．１ｍｌ接种１０日龄ＳＰＦ鸡胚尿囊腔１５０小时内，鸡胚极少死亡。每个滴度５个胚有尿液均可凝集鸡红血球。第１０代和第２０代的每个滴度５个胚有的混合尿液以１０＾－６×０．５ｍｌ一次饮水免疫鸡，即能引起ＨＩ抗体反应，也能抵抗新城疫强     

昆虫细胞与幼体生物反应器的应用—蛋白质产品规模化生产方法

蜡状芽孢杆菌是新发现的一种杀虫效率高，杀虫速度快的杀蝗微生物，用４．４×１０＾６和４．４×１０＾７孢子／ｍｌ接种棉蝗大龄跳蝻及成虫，棉蝗的死亡率分别达到８２．６％和８０．８％。毒力测定结果ＬＣ５０为２．７×１０＾８孢子／ｍｌ。林间大试验，杀虫效果达７７．９％。     

猪带绦虫六钩抗原基因的克隆与表达

以λｇｔ１１为载体构建了猪带绦虫钩蚴ｃＤＮＡ文库，从中筛选出５株表达六钩蚴抗原成分的重组噬菌体。将其中的六钩蚴ｃＤＮＡ与表达质粒ＰＧＥＸ－４Ｔ２连接，在ＴＧ１大肠杆菌中高效表达，获得了２株表达ＧＳＴ－六钩蚴抗原融合蛋白（Ｍｒ分别为５×１０＾４和６×１０＾４）的工程菌。在ＬＢ营养液中添加１％乳糖和０．２％葡萄糖，工程菌的表达效果优于用ＩＰＴＧ诱导的效果。融合约占工程菌总蛋白２３％。     

饲粮中脱毒菜籽饼水平对生长猪的影响

将长白×荣昌杂交一代仔猪（２０ｋｇ左右）７５头随机分成５组，每组１５头。在饲粮中加入占总量的０％、１０％、１５％、１８％和２０％的脱毒菜籽饼，并使供试５种饲粮的营养水平基本相同。经６０天试验，平均日增重，第１、２、３组与第５组差异极显著（Ｐ＜０．０１），第４组与第５组差异显著（Ｐ＜０．０５），第１－４组间差异不显著（Ｐ＞０．０５）。饲料报酬，第１组与第５组差异显著（Ｐ＜０．０５），其他各组间差异不显著（Ｐ＞０．０５）；每千克增重需饲料成本，以第４组最低，第５组最高。     

伊氏锥虫半—大规模体外培养初报

按改良Ｂａｌｔｚ无细胞培养系统的培养方法，将盛有３００ｍＬ伊氏锥虫培养物，容量１７００ｍＬ（１１．０ｃｍ×２８．５ｃｍ）的培养瓶置于１０ｒ／ｍｉｎ的细胞培养旋转装置上，在３７℃培养箱中培养。在接种虫数为１．５×１０＾５～１０．０×１０＾５／ｍＬ时，其群体增倍时间为１２ｈ。接种虫数为１０×１０＾５／ｍＬ的培养物培养２４ｈ，每瓶收获约１．２×１０＾９锥虫，可满足一般实验的需要。     

植酸酶对生长猪生产性能及养分利用率的影响

用一个饲养试验和一个消化代谢试验研究了植酸酶对生长猪生产性能和养分消化率的影响。饲养试验将９６头和２０ｋｇ左右的长白×荣昌Ｆ１杂交猪９６头,随机分为８组,每组４个圈,每圈３头,分别喂给基础日粮,基础日粮＋０．８％磷酸氢钙,基础日粮＋１０×１０＾－５,２０×１０＾－５,３０×１０＾－５,４０×１０＾－５植酸酶,基础日粮＋０．８％磷酸氢钙＋２０×１０＾－５或４０×１０＾－５植酸酶等８种日粮。     

鼠伤寒沙门氏菌和福氏志贺氏菌流行株耐药质粒的研究

对分离到的９株鼠伤寒沙门氏菌和５株福氏志贺氏菌进行药敏试验、质粒提取和电泳分析，各菌株均分离出２－４条粒带。将含有３．２７×１０＾４，３．０１×１０＾４和６．０１×１０＾４ｂｐ的持粒转化给大肠埃希氏菌ＨＢ１０１，使ＨＢ１０１获得了相应菌的部分耐药性，用转化有３．２７×１０＾４ｂｐ的ＨＢ１０１注射小白鼠，１５ｄ后用相应的原始鼠伤寒沙上氏菌强毒株攻击，结果使小白鼠获得了保护；用含有３．２７×１０＾４ｂ     

母猪孕期过长引起死胎的治疗体会

笔者在临床上用已烯雌酚（南京动物激素厂生产）和缩宫素（人用）治疗母猪孕期过长引起死胎５例，均能使死胎全部排出母猪体外，取得令人满意的效果。现介绍如下，供同仁参考。１　治疗方法临产母猪体重约在１００千克左右，第１天上午（第一次）已烯雌酚６毫克×２，肌注；下午（第二次）己烯雌酚６毫克×４，肌注；第２天上午（第三次）己烯雌酚６毫克×４；下午（第四次）己烯雌酚６毫克×２，缩宫素１０μｇ×５混合肌注。２　典型病例２．１　１９９７年１０月７日，双桥镇双桥村快上屯黄某家饲养的一头３岁母猪超出正常孕期６天后求诊…     

蜂王浆中溶性蛋白质分子量的探讨

本研究采用ＳＤＳ－聚丙烯酰胺凝胶电泳，对５０种采样自不同来源的蜂王浆样品测定结果表明，蜂王浆中含有５－９种溶性蛋白，其分子量分布范围为２．０８×１０＾４～１３．５６×１０＾４。     

Immunization of young chickens by trickle infection with Eimeria tenella.

Immunization of chickens was attempted with low levels of Eimeria tenella oocysts (50 oocysts per day) over the first 1 or 2 weeks of life--the "trickle infection" (TI) method. When chickens were immunized by TI at 0-13 days of age, no cecal lesions and a reduced number of oocysts in ceca were observed after challenge at 17 days of age. TI at 0-6 days of age conferred better protection against challenge with E. tenella than did TI at 7-13 days. However, cecal lesions were observed in almost all of these chickens. These findings indicated that TI for 2 weeks (0-13 days of age) provided better immunity than TI for 1 week (0-6 or 7-13 days of age).     

The histological observations on the large intestine of the goose (Anser anser) during the pre- and post-hatching periods

The development of the cecum and colon in the goose was investigated during the period from the 15th to 28th day of the incubation and from 1 to 30 days of age after hatching by light microscopy. By day 15 of the incubation, in the cecum and colon, the lumen was surrounded by pseudostratified epithelium. The previllous ridges appeared at 15th and 17th days of the incubation in the colon and ceca, respectively. At the base of previllous ridges, the epithelium changed into a simple prismathic epithelium at 15th and 17th days of the incubation in the colon and cecum, respectively. The villi appeared at the 21st days of the incubation. The crypts and goblet cells appeared on the first day after hatching. In the pre-hatching period, the lamina muscularis mucosa was present only in the colon. The submucosa consisted of loosely aggregated connective tissue in the pre-hatching period. In the post-hatching period, it consisted of a very thin layer of connective tissue. Its presence was only obvious where the cells of the submucosal nerve plexus or occasional large blood vessels considerably increased its thickness. The nerve plexus corresponding to the Auerbach's plexus of the mammalian intestine and submucosal nerve plexus appeared by 15th days of the incubation. From the 15th to 28th day of incubation, the tunica muscularis consisted of circular smooth muscle cells in the ceca. On the 28th day of the incubation a thinner longitudinal muscle layer added to the circular muscle layer. In the colon there was an outer longitudinal and a thicker circular muscle layer.     

11株巨型艾美耳球虫繁殖力的比较研究

用巨型艾美耳球虫扬州株、南通株、连云港株、苏州株、凤阳株、青岛株、福州株、龙岩株、广州株、上海株和美国株孢子化卵囊100个/只或10 000 个/只,经嗉囔接种7 日龄或21 日龄无球虫黄羽肉公雏,以麦克马斯特法对感染后第6 天至第14 天间每天24 h排出的卵囊计数并进行统计分析。结果表明,各虫株的排卵囊量有差异,100个/只卵囊感染7日龄雏鸡时,广州株和凤阳株排卵囊量最多,上海株和苏州株排卵囊量最少;100个/只卵囊感染21 日龄雏鸡时,扬州株排卵囊量最多,上海株排卵囊量最少;10 000 个/只卵囊感染21 日龄雏鸡时,苏州株排卵囊量最多,连云港株和扬州株的排卵囊量最少;排卵囊量随着感染剂量的增加或鸡日龄的增大而增多;在同一感染剂量时,福州株和连云港株增加最多,上海株和苏州株增加最少;在同一感染鸡日龄时,苏州株和上海株增加最多,南通株和扬州株增加最少;各虫株的排卵囊规律极相似,在感染后第7 天排卵囊量达峰值,第8 天、第9 天排出的卵囊量显著减少,第10天排出的卵囊量仅占总量的2%,第14天接近于0%;第6天至第8天排出的卵囊量占总量的87%~99%。     

Prevention of shedding and re-shedding of Toxoplasma gondii oocysts in experimentally infected cats treated with oral Clindamycin: a preliminary study

This work aimed to evaluate the effects of preventive oral Clindamycin in cats infected with Toxoplasma gondii. Twelve short hair cats were divided into two groups (group 1 and group 2). No titres of T. gondii antibodies were detected in these cats before the experiment. The animals from group 1 were infected with tissue cysts of T. gondii and group 2 were infected and treated with Clindamycin (20 mg/kg/day). The infection was done with almost 40-50 tissue cysts for each cat on day 0. The cats from group 2 were treated with Clindamycin by oral rout for 24 days (from day -3 to day 21). At day 45, the groups 1 and 2 were divided into two subgroups with three animals each. Subgroups 1A and 2A were immunosuppressed with dexamethasone (1 mg/kg/day) for30 days and subgroups 1B and 2B were not immunosuppressed. Faecal exam looking for oocyst shedding was made by 30 days after T. gondii infection, and for 30 days after immunosuppression. All kittens from group 1 shedding oocysts after infection, while animals from group 2 did not shed. After immunosuppression period, all animals from group 1A re-shed oocysts and animals from group 2A remained without shed. However, 2 (66.6%) of the kittens from subgroup 2B shed oocysts 19-20 days after re-challenge. Based on this preliminary study, Clindamycin had a complete inhibitory effect on shedding of oocysts by cats, even under severe immunosuppression, which is a new finding not reported elsewhere.     

Infectivity to hosts of the endogenous stages of chicken and murine Cryptosporidium.

Five groups of 4 mice each were inoculated with 10(6) Cryptosporidium muris oocysts. They were necropsied on days 2, 4, 6, 8 and 10. The stomach mucosa from each group were made into 10% suspension in physiological saline and were orally inoculated to 2 mice each. Recipients given suspension from infected mice on day 6, 8 and 10 shed oocysts from 6, 9 and 6, respectively. Similarly, White Leghorn received 10(6) Cryptosporidium sp. oocysts were killed daily between 1 and 6 days. Recipients given bursa of Fabricius or caecum of donor birds on days 4, 5 and 6 shed oocysts. The endogenous stages of murine and chicken Cryptosporidium were able to infect the appropriate host.     

Coccidiostatic action of monensin fed to lambs: body weight gains and feed conversion efficacy.

Thirty crossbred ewe lambs weighing an average of 37.3 kg were allotted to 6 groups of 5 lambs each so that group weights were nearly equal. Lambs were fed dehydrated alfalfa pellets, initially at 1.14 kg/day and subsequently increased after experimental day 15 and 42. Each lamb was artificially infected with 18,000 sporulated oocysts of Eimeria ninakohlyakimovae. Groups 1, 2, 3, and 4 were given monensin in the form of medicated alfalfa pellets at dose levels of 5, 10, 20, and 30 g/metric ton, respectively. Groups 5 and 6 were infected controls (infected, nonmedicated). Lambs in groups 5 and 6 developed severe clinical coccidiosis, having diarrhea and losing weight rapidly. Group 1 lambs did not have diarrhea, but the lambs did not gain well. All other medicated lambs gained weight during the experimental period of 84 days. Feed conversion was good in medicated groups 2, 3, and 4 and was poor in control groups 5 and 6. Statistically significant differences in feed conversion and body weight gains (5 and 1% level of confidence) were observed between control and medicated groups.     

Pathogenic Effiects of the Coccidium Eimeria ninakohlyakimovae in Goats

Twenty-four coccidia-free goats were reared artificially in indoor cages and allocated to 6 groups of 4 animals each. At 20 days of age, goats in groups 1–3 received 10⁴,10⁵ and 10⁶ sporulated oocysts of Eimeria ninakohlyakimovae per goat, respectively, each as a single dose. Goats in group 4 received daily doses increasing over a 3-week period, starting with 100/day for the first week, followed by 1000, and 10 000/day in weeks 2, 3, respectively. Goats in group 5 received 10⁴ oocysts following a challenge dose of 10⁶ oocysts on day 32. Goats in group 6 were kept as uninoculated controls. Infected animals showed diarrhoea and weight loss. Goats in group 4 showed longer periods of diarrhoea and patency than other infected goats. Goats in group 5 showed the same severe clinical signs as those in group 3 but produced very low oocyst output after a challenge dose. The diarrhoea was associated with a reduction in alkaline phosphatase activity and increases in packed cell volume and haemoglobin. No significant differences were found in serum aspartate aminotransferase, alanine aminotransferase, total protein, albumin, globulin, Na⁺, K⁺,Cl⁻ between groups during 48 days after inoculation. There were no serum enzyme indications of damage to the liver. Histological examination performed 100 days after inoculation revealed that inoculated goats had mild subacute to chronic proliferative enteritis in the lower small intestine and the large intestine, and the mesenteric lymph nodes, gallbladders and livers also showed slight histological lesions. The results showed that E. ninakohlyakimovae was highly pathogenic.     

假蒟提取物对感染柔嫩艾美耳球虫鸡血液指标的影响

本试验旨在研究假蒟提取物对感染柔嫩艾美耳球虫鸡血液指标的影响。270只1日龄海南文昌公鸡,随机分为6个组,每组3个重复,每重复15只,T1、T2和T3组为对照组(依次分为不感染不给药组、感染不给药组、感染给药组);T4、T5和T6组为假蒟添加组,分别在基础日粮中添加200、400、600mg/kg假蒟提取物粉剂。15日龄时,每组随机抽取30只鸡,除T1组灌服生理盐水外,其他各组鸡均经口接种柔嫩艾美耳球虫卵囊悬液,分别于接种前1d,接种后3、6、9d清晨采血测定其血液指标。结果表明,与感染球虫不给药的T2组相比,假蒟组(T4、T5、T6)可以显著降低感染球虫鸡粪便中球虫卵囊值(P0.05)。假蒟组在感染球虫后第6天,与T1组比,RBC、HGB、HCT、Ca2+、Na+、Cl-、TP、ALB、GLB、TG、CHOL、T4等指标呈下降趋势;但在感染球虫后第9天,TP、GLB含量均显著高于T1组(P0.05);在感染球虫后第6天,假蒟组与对照组相比,ALT、AST浓度水平均显著降低(P0.05)。结果提示,假蒟提取物能提高感染球虫后鸡机体免疫机能,降低肝脏损伤,降低鸡感染球虫后粪便卵囊值,具有一定的抗球虫效果。     

堆型艾美耳球虫早熟株免疫雏鸡后血清抗体水平动态变化的研究

用堆型艾美耳球虫早熟株对雏鸡进行一次免疫和二次免疫试验 ,研究雏鸡血清抗体的动态变化。试验结果显示 ,在一次免疫试验中 ,各剂量组雏鸡均在免疫后 2天血清抗体出现较高的 OD值 ,之后呈下降趋势 ,11天后逐渐上升 ,到 12～ 13天时出现第 2个峰值 ,各组间的血清抗体 OD值比较 ,3 0 0 0个卵囊 /只剂量组极显著 (P<0 .0 1)高于 10 0 0个 /只、2 0 0 0个 /只和 5 0 0 0个 /只剂量组。在二次免疫试验中 ,8日龄首免、14日龄二免组雏鸡的抗体水平动态变化整体呈上升趋势 ,峰值 (0 .3 75 )出现在二免后第 10天 ,其后稳定地维持在较高水平 (平均 OD值为 0 .3 5 ) ,并且其抗体水平显著地高于 6日龄首免、12日龄二免组 (P<0 .0 5 )。抗体水平动态变化表明 ,堆型艾美耳球虫早熟株有较强的免疫保护力 ,其免疫方式可选用一次免疫 ,剂量为 3 0 0 0个卵囊 /只 ,也可采用二次免疫 ,即 8日龄首免 (15 0 0个 /只 ) ,14日龄二免 (15 0 0个 /只 ) ,从抗体动态变化的稳定性看 ,二次免疫更佳