N-乙酰半胱氨酸对脂多糖刺激仔猪小肠黏膜免疫应激的影响

研究N-乙酰半胱氨酸(NAC)对脂多糖(LPS)刺激仔猪免疫应激的影响。选取18头健康仔猪,随机分成3个处理(对照组、LPS组和NAC组),每个处理6个重复。对照组和LPS组饲喂基础日粮,NAC组饲喂基础日粮+500 mg/kgNAC。试验期为20 d。LPS组和NAC组于试验第10、13、20天腹膜注射100μg/kg BW的LPS,对照组注射相应剂量的灭菌生理盐水。第10、20天注射LPS后3 h采血,第21天屠宰,取小肠黏膜。结果表明:NAC缓解了LPS刺激导致的血浆和小肠黏膜中TNF-α、IL-6、PGE2含量的升高(P<0.05),缓解了小肠黏膜HSP70相对表达量的升高(P<0.05)。由此可见,日粮中添加500 mg/kg NAC可有效抑制LPS刺激导致的血浆及小肠黏膜中炎性因子的升高,缓解免疫应激。     

牛膝多糖对免疫应激仔猪生长性能、炎性介质和内分泌激素的影响

试验旨在探讨牛膝多糖(ABPS)对脂多糖(LPS)刺激的断奶仔猪生长性能、炎性介质和内分泌激素的影响。选用48头(28±3)d(8.45±0.14)kg的杜洛克×长白×大白断奶仔猪,采用2×2因子设计,包括日粮处理(0或500 mg/kg ABPS)和免疫应激(注射LPS或生理盐水)。试验期28 d。在第14天和第21天,每日粮组一半的猪注射100μg/kg BW的LPS,另一半注射生理盐水作对照。注射后3 h,采血测定血浆肿瘤坏死因子-α(TNF-α)、前列腺素E2(PGE2)、皮质醇、生长激素(GH)和类胰岛素生长因子-I(IGF-I)含量。结果表明:LPS刺激显著降低了第14~21、22~28天的日增重(ADG)和日采食量(ADFI)(P<0.05或P=0.05);ABPS显著提高了22~28 d的ADG(P<0.05)。LPS刺激显著提高了14 d和21 d的TNF-α、PGE2和皮质醇的含量,降低了IGF-I的含量(P<0.01);ABPS显著缓解了LPS刺激导致的TNF-α(14 d和21 d)和皮质醇(14 d)含量的上升以及IGF-I(14 d和21 d)含量的下降(P<0.05)。说明ABPS缓解了免疫应激仔猪生长的抑制,其机制可能与其抑制了炎性介质的分泌有关。     

N-乙酰半胱氨酸对脂多糖刺激仔猪免疫应激和能量状况的影响

本研究旨在N-乙酰半胱氨酸(NAC)对脂多糖(LPS)刺激仔猪肝脏免疫应激和能量状况的影响及其机理进行探讨.选取18头健康仔猪(杜洛克×长白×大白,体质量(11.58±0.26)kg),随机分成3个处理(对照组、LPS组和NAC组),每个处理6个重复,每个重复1头猪.对照组和LPS组饲喂基础日粮,NAC组饲喂基础日粮+500 mg·kg-1 NAC,LPS和NAC组仔猪分别于试验的第10、13、20天腹膜注射100 μg·kg-1 BW的LPS,对照组注射等量的灭菌生理盐水.第10、20天注射LPS后3h前腔静脉采血,第21天仔猪麻醉后进行屠宰,取肝脏样品待测.试验结果显示:(1)日粮中添加NAC显著缓解了LPS刺激导致的ADG降低(P＜0.05)和F/G的升高(P ＜0.05).(2)日粮中添加NAC缓解了LPS刺激导致的血浆、肝脏中TNF-α、IL-6和PGE2的升高(P＜0.05).(3)日粮中添加NAC缓解了LPS刺激导致的肝脏核因子-κB(NF-κB)和热休克蛋白70 (HSP70)蛋白表达量的升高(P＜0.05).(4)日粮中添加NAC缓解了LPS刺激导致的肝脏中三磷酸腺苷(ATP)、二磷酸腺昔(ADP)和能荷(EC)水平的降低(P＜0.05)及一磷酸腺苷(AMP)水平和AMP/ATP比值的升高(P＜0.05).由此可见,日粮中添加500 mg·kg-1 NAC可能通过缓解LPS导致的免疫应激和能量的过度损耗,促进仔猪生长.     

N-乙酰半胱氨酸对脂多糖单次刺激仔猪肠黏膜免疫应激的影响

本试验旨在研究N-乙酰半胱氨酸(NAC)对脂多糖(LPS)单次刺激仔猪肠黏膜免疫应激的影响。选取24头健康仔猪,随机分成4组,每组6个重复,每个重复1头猪。对照组和LPS组饲喂基础饲粮,250和500 mg/kg NAC组在基础饲粮中分别添加250和500 mg/kg NAC。试验第17天,LPS组、250和500 mg/kg NAC组仔猪腹膜分别注射100μg/kg BW的LPS,对照组注射相应剂量的灭菌生理盐水。注射后6 h屠宰,取肠黏膜。结果表明:与对照组相比,饲粮中添加250或500 mg/kg NAC缓解了LPS刺激导致的肠黏膜中白细胞介素-2、白细胞介素-6和前列腺素E2水平的升高及热应激蛋白70(HSP70)表达量的升高(P<0.05)。由此可见,饲粮中添加250和500 mg/kg NAC可有效抑制LPS刺激导致的肠黏膜中炎性因子的升高,缓解急性免疫应激。     

N-乙酰半胱氨酸对脂多糖应激仔猪生长性能及血浆生化指标的影响

本文旨在研究N-乙酰半胱氨酸(NAC)对脂多糖(LPS)应激仔猪生长性能及血浆生化指标的影响.选取来源一致、平均体重(11.58±0.26)kg的24头健康仔猪,随机分成2组,每组6个重复,每重复2头仔猪.试验分2个阶段,第1～9天对照组饲喂基础饲粮,试验组饲喂在基础饲粮中添加500mg/kg NAC.试验第10～20天分别将2个组同一重复猪中1头分出单独饲养,于第10天、第13天和第20天,1头仔猪腹膜下注射100mg/kg LPS,另一头仔猪注射等体积生理盐水.结果显示:1)饲粮中添加NAC可以缓解LPS刺激导致的日增重下降(P<0.05);2)饲粮中长时间添加NAC能极显著提高仔猪血浆谷胱甘肽水平(P<0.01),显著提高血浆超氧化物歧化酶活性(P<0.05),显著提高血浆表皮生长因子水平(P<0.05).由此可见,饲粮中添加NAC可缓解LPS应激导致的抑制仔猪生长.     

刺五加多糖对脂多糖免疫应激断奶仔猪生长性能和血液生理生化指标的影响

本试验旨在探讨饲粮中添加刺五加多糖(Acanthopanax senticosus polysaccharide,ASPS)对脂多糖(LPS)免疫应激断奶仔猪生长性能和血液生理生化指标的影响。试验采用2×2两因素设计,即饲粮处理(添加0或800 mg/kg ASPS)和免疫应激处理(注射LPS或生理盐水)。将64头(28±3)日龄、平均体重为(7.22±0.46)kg的"杜×长×大"三元杂交断奶仔猪随机分为4个处理,其中处理1和2饲喂基础饲粮(添加0 mg/kg ASPS),处理3和4饲喂试验饲粮(添加800 mg/kg ASPS),试验第14和21天,处理2和4仔猪腹腔注射100μg/kg BWLPS,处理1和3仔猪腹腔注射等量生理盐水。注射后3 h采血,测定血液生理生化指标。试验期21 d。结果表明:试验1～14 d,饲喂ASPS对未注射LPS的仔猪生长性能无显著影响(P>0.05);试验15～21 d,饲喂ASPS显著增加仔猪的平均日增重(ADG)和平均日采食量(ADFI)(P<0.05),且饲喂ASPS使注射LPS的仔猪ADG和ADFI显著增加(P<0.05),但对注射生理盐水的仔猪无显著影响(P>0.05)。饲喂ASPS对仔猪ADG的影响与LPS刺激存在显著互作关系(P<0.05)。试验第14天,饲喂ASPS显著提高了仔猪外周血淋巴细胞数量(P<0.05),对外周血淋巴细胞数量的影响与LPS刺激存在显著的互作关系(P<0.05),且饲喂ASPS能显著增加注射LPS的仔猪外周血淋巴细胞数量(P<0.05),但对注射生理盐水的仔猪无显著影响(P>0.05)。试验第14和21天,饲喂ASPS显著降低了仔猪血浆α-酸性糖蛋白(α-AGP)、葡萄糖、前列腺素E2(PGE2)含量(P<0.05),显著提高了血浆白细胞介素-2(IL-2)含量(P<0.05),且其对α-AGP、IL-2、PGE2含量的影响与LPS刺激存在显著的互作关系(P<0.05),饲喂ASPS能显著降低注射LPS的仔猪血浆α-AGP、PGE2含量(P<0.05),但对注射生理盐水的仔猪无显著影响(P>0.05)。由此可见,饲喂ASPS对非免疫应激断奶仔猪的生长性能无影响,但可以缓解免疫应激断奶仔猪的生长抑制,ASPS缓解免疫应激断奶仔猪生长抑制与降低其血浆α-AGP和PGE2含量,提高外周血淋巴细胞数量和血浆IL-2含量有关。     

脯氨酸对脂多糖多次刺激的仔猪生长性能及血液生化指标的影响

试验研究了脯氨酸(proline,PRO)对脂多糖(LPS)多次刺激的仔猪生长性能、血液生化指标的影响。选取来源一致、体重相近([9.13±0.85)kg]的健康断奶仔猪36头,采用2×3因子试验设计。设免疫应激和PRO添加量2个因子,其中免疫应激设2个水平:无应激(不注射LPS,注射相同剂量的生理盐水)和LPS刺激(腹膜注射100μg/kgBWLPS);PRO添加量设3个水平:0、0.5%和1.0%。共6个处理组,每个处理6个重复,每重复1头仔猪,试验期20d。试验前10d,未进行LPS处理,于试验的第10、13和20d对应激组仔猪腹膜注射100μg/kgBWLPS,无应激组仔猪注射相应剂量的生理盐水。试验第10、20d空腹称重,并于注射LPS3h后前腔静脉采血,观测有关指标。试验结果显示:①LPS刺激降低了仔猪生长性能、提高了血浆中尿素氮,对过氧化氢酶(CAT)、丙二醛(MDA)和超氧化物歧化酶(SOD)均无影响。②日粮添加PRO可以显著降低血浆BUN和MDA,提高血浆SOD,以0.5%的效果较好。在本次试验条件下,LPS刺激显著降低了仔猪的生长性能,提高了血浆中尿素氮水平,日粮添加0.5%的PRO可提高机体抗氧化能力和降低血浆中尿素氮水平;添加脯氨酸对LPS刺激导致的生长抑制没有缓解作用。     

谷氨酰胺对免疫应激仔猪肌肉中理化指标的影响

试验研究谷氨酰胺对免疫应激仔猪肌肉中理化指标的影响。采用2×2析因试验设计,选用28 d平均体重7 kg的长白×约克夏断奶仔猪96头,按体重相近原则随机分为4组。对照组(Ⅰ组)、免疫应激组(Ⅱ组)饲喂基础日粮,断奶后7 d分别注射100μg/kg BW生理盐水、LPS;谷氨酰胺组(Ⅲ组)、谷氨酰胺+免疫应激组(Ⅳ组)饲喂含谷氨酰胺浓度为1.2%的日粮,断奶后7 d分别注射100μg/kg BW生理盐水和LPS。试验期14 d。结果表明:LPS应激极显著提高了仔猪肌肉中乳酸含量(P<0.01),极显著降低了总蛋白、丙氨酸氨基转移酶、过氧化氢酶、谷胱甘肽含量(P<0.01),而谷氨酰胺的添加缓解了这几项指标的显著变化,且日粮类型与LPS应激均存在交互作用(P<0.01),说明日粮中添加谷氨酰胺可缓解免疫应激,对免疫应激仔猪具有保护作用。     

α-酮戊二酸对脂多糖刺激仔猪血液生化指标、血液激素水平和炎性细胞因子水平的影响

试验旨在探讨α-酮戊二酸(AKG)对脂多糖(LPS)刺激仔猪血液生化指标、血液激素水平和炎性细胞因子水平的影响。选取24头(24±1)日龄健康断奶仔猪,随机分成3个处理组(空白对照组、应激对照组、AKG组),每个处理8个重复。各组基础日粮一致,空白对照组和应激对照组饲喂基础日粮,AKG组饲喂基础日粮+1%AKG。试验期为16d,应激对照组和AKG组仔猪分别于第10、12、14和16d腹膜注射80μg/kgBW的LPS,空白对照组注射相应剂量的灭菌生理盐水。第10、16d注射LPS3h后,前腔静脉采血。LPS刺激降低了第10d血浆总蛋白(TP)、球蛋白水平(GLO)、白蛋白/球蛋白比值(A/G)(P0.05),降低了第10d和16d表皮生长因子(EGF)、提高了第16dGLO和第10d肿瘤坏死因子-α(TNF-α)水平(P0.05)和白介素(IL)-6水平(P0.1),日粮中添加AKG使血浆GLO水平及A/G值维持在正常水平,缓解了第10d和16dEGF的降低及第10dTNF-α和IL-6的升高(P0.05)。AKG可以在一定程度上缓解LPS刺激导致的应激反应。     

α-酮戊二酸对免疫应激仔猪肝脏氨基酸代谢的影响

试验研究了α-酮戊二酸(AKG)对免疫应激下仔猪氨基酸代谢的影响。将24头(24±1)日龄仔猪[杜×长×大,体重(7.25±0.23)kg]随机分为3个处理组,每个处理组设8个重复,每个重复1头猪。3个处理组分别为:对照组、应激对照组(LPS组)、试验组(AKG组)。各组基础日粮一致,空白对照组和应激对照组饲喂基础日粮+1%淀粉,AKG组饲喂基础日粮+1%AKG。试验期为17d。在试验第10、12、14和16d分别在LPS组和AKG组仔猪的腹膜注射80μg/kgBW脂多糖(LPS),对照组注射相应剂量的灭菌生理盐水。第17d清晨屠宰空腹仔猪,取肝组织样品,分析游离氨基酸含量。结果显示:免疫应激导致仔猪肝脏酪氨酸(Tyr)含量显著下降了81.82%(P0.05),赖氨酸(Lys)的含量有下降的趋势(P0.1),AKG组仔猪肝脏的Tyr、Lys含量与LPS组和对照组差异均不显著;丙氨酸(Ala)的含量较LPS组有升高的趋势(P0.1),谷氨酸(Glu)的含量较对照组和LPS组均有上升的趋势(P0.1)。以上结果表明:AKG能在一定程度上缓解免疫应激对仔猪氨基酸代谢的影响,减轻LPS刺激对仔猪肝脏损伤。     

H9N2亚型禽流感病毒传播途径特性的比较及其表面基因序列分析

选择中国大陆最早分离的H9N2亚型禽流感病毒(avian influenza virus,AIV)A/Chicken/Guangdong/SS/94(H9N2)(缩写为SS株)和1998年大流行时期分离的H9N2亚型AIVA/Chicken/Shanghai/F/98(H9N2)(缩写为F株)为研究对象,对其在SPF鸡体内的复制能力和传播途径特性比较后发现,F株在4周龄SPF鸡气管中的复制能力高于SS株,F株可以经气溶胶传播途径传播,SS株不能经气溶胶传播途径传播;利用反转录-聚合酶链反应(RT-PCR)方法获取F株和SS株的HA和NA基因的cDNA,序列分析得知,F株和SS株的HA和NA基因的同源性分别是96.6%和98.1%;HA基因的裂解位点氨基酸序列都是PARSSR↓GL,但有5个氨基酸的差异,即166位N(F)→D(SS)、198位A(F)→V(SS)、217位V(F)→I(SS)、335位G(F)→R(SS)、504位L(F)→S(SS);2株病毒的NA基因在63~65位都存在氨基酸缺失,但在NA基因红细胞吸附位点的氨基酸序列不同,分别是IKKDSRSG(F)和IKEDLRSG(SS)。F株和SS株的传播特性差异是否与其表面基因序列有关,有待进一步研究。     

禽类的起源、演化及我国主要家禽品种类型与分布

家禽是重要经济价值动物.本文从禽类种群进化学说出发,简介了禽类的起源、演化、动物学分类和家禽的驯化(养)与品种的形成,并对我国主要家禽(鸡、鸭、鹅)地方品种和培育品种(配套系)的分布与类型作了描述,以期为研究我国家禽起源系统,保护与利用我国家禽品种,促进家禽生产可持续发展提供参考.     

一起猪链球菌病和伪狂犬病的混合感染的诊治

近年以来,由于市场因素的刺激,生猪的存养量大幅上升,再加上由于流通环节较多,流通非常频繁,流通距离越来越远。这对繁荣经济,增加养殖效益起了重要的推动作用,但也同时给疾病的感染和传播创造了有利条件,给猪病的防治带来了困难。有的猪场感染了传染病后,由于治疗不及时不得法,而造成了惨重的经济损失。2008年7月中旬,我街道一养猪户因盲目从外地购进中猪,发生猪病疫情,引起猪只连续死亡,造成一定的经济损失。根据流行病学、临床症状、剖检变化和实验室诊断,诊断该病为猪链球菌病和猪伪狂犬病混合感染,现报告如下。     

秋冬季预防和治疗虫媒性传染病鸡白冠病和鸡痘

１前言１．１鸡白冠病鸡白冠病是由卡氏住白细胞原虫寄生于鸡的红细胞和单核细胞而引起的鸡的贫血性疾病。吸血昆虫蚋和库蠓叮咬鸡引起传播，是主要的传播媒介，一般在夏末和秋季多发，由于夏季降雨量较大，部分沟渠积水，库蠓和蚋多孳生，因此在多雨水涝的年份发病率明显增高。１９９８年中国从南到北发生洪涝灾害，吸血昆虫的孳生格外严重，出现了一个白冠病多发年，而后两年发病稍轻，并有地区性，今年８月中旬以来白冠病的发病呈抬头趋势，有一定的死亡率，对蛋鸡产蛋率也会引起一定程度的降低，应引起养鸡户的重视。１．２鸡痘鸡痘也是…     

种鹅矛形剑带绦虫与背孔吸虫混合感染的诊治

2005年9月份,大庆市红岗区个体养鹅专业户送检6只病死的5月龄左右隆昌鹅和长白鹅,经过实验室诊断确诊为矛形剑带绦虫与背孔吸虫混合感染。矛形剑带绦虫属膜壳科     

Evaluation of lysozyme and lactoferrin in lacrimal and other ocular glands of bison and cattle and in tears of bison

OBJECTIVE: To evaluate lactoferrin and lysozyme content in various ocular glands of bison and cattle and in tears of bison. SAMPLE POPULATION: Tissues of ocular glands obtained from 15 bison and 15 cattle and tears collected from 38 bison. PROCEDURE: Immunohistochemical analysis was used to detect lysozyme and lactoferrin in formalin-fixed, paraffin-embedded sections of the ocular glands. Protein gel electrophoresis was used to analyze ocular glands and pooled bison tears by use of a tris-glycine gel and SDS-PAGE. Western blotting was used to detect lactoferrin and lysozyme. RESULTS: Immunohistochemical staining for lactoferrin was evident in the lacrimal gland and gland of the third eyelid in cattle and bison and the deep gland of the third eyelid (Harder's gland) in cattle. Equivocal staining for lactoferrin was seen for the Harder's gland in bison. An 80-kd band (lactoferrin) was detected via electrophoresis and western blots in the lacrimal gland and gland of the third eyelid in cattle and bison, Harder's glands of cattle, and bison tears. An inconsistent band was seen in Harder's glands of bison. Lysozyme was not detected in the lacrimal gland of cattle or bison with the use of immunohistochemical analysis or western blots. Western blots of bison tears did not reveal lysozyme. CONCLUSIONS AND CLINICAL RELEVANCE: Distribution of lactoferrin and a lack of lysozyme are similar in the lacrimal gland of cattle and bison. Differences in other tear components may be responsible for variability in the susceptibility to infectious corneal diseases that exists between bison and cattle.     

Shape and size of teeth of dogs and cats-relevance to studies of plaque and calculus accumulation

Crown width, height and buccal surface areas were measured on heads or skulls of four dogs and four cats, and were compared with similar measurements on models of human dentition. Buccal surface area variability was greater in dogs and cats than in humans, and teeth of cats were smaller. Horizontal (gingival and occlusal halves) and vertical (mesial, middle, and distal thirds) buccal surface area variability was also greater in canine and feline teeth compared with human teeth. This increased variability suggests the need for testing of reliability and repeatability of scoring when using plaque and calculus indices based on horizontal or vertical segmentation. Buccal surface area variability between teeth also prompts questioning the validity of equal weighting of smaller, irregularly-shaped teeth when calculating a mean mouth score. Whether equal or more reliable results would be obtained from scores of whole teeth in comparison with segmentation indices used currently has yet to be determined.     

Description and classification of abnormal cercariae of Schistosoma mattheei and a method of concentration and collection

Over a period of about 12 years, 30 abnormal Schistosoma mattheei cercariae were found among a total of approximately 2.8 million examined. Initially seven were recovered from about 1.02 million (0.0007%), which were examined individually while being counted with the aid of a stereoscopic microscope. Subsequently, on the strength of relatively high percentages of abnormal individuals recovered when counting cercariae that failed to penetrate into oxen, it appeared that the morphologically abnormal cercariae were unable to swim and would mostly sediment out of a suspension while most of the normal cercariae would remain swimming. This surmise is supported by recovery of 23 morphologically abnormal cercariae (0.001%) from about 1.8 million, by examining the sediment after the cercarial suspension had been left standing undisturbed in glass measuring cylinders. The abnormalities ranged from aberrant tails only (e.g. an underdeveloped tail, or different degrees of schism) or aberrant heads only, to abnormalities of both the heads and tails. A suggested schematic classification of abnormal cercariae is presented. A young, adult hamster was exposed to eight S. mattheei cercariae with complete schism of the shaft of the tail, by pipetting the cercariae onto the shaved abdominal skin of the anaesthetised animal. Two underdeveloped females were subsequently encountered in squash preparations of the liver when the hamster was killed for worm recovery 10 weeks after infection, thus showing that some of the abnormal cercariae were viable. A method is also described for killing and fixing cercariae while retaining some of the shining brilliance of live cercariae, without them becoming shrivelled, granular and semi-opaque, as occurs when cercariae die spontaneously or are killed with heat. This is apparently the first report of abnormal cercariae of S. mattheei. In addition, a method of concentrating abnormal cercariae after emergence from a snail, a schematic classification of abnormal cercariae and a method for killing and fixing cercariae while retaining much of the shiny brilliance of live cercariae are also reported for the first time as far as is known.