预消化蛋白对肉鸡生长性能、免疫性能和肠道形态学的影响研究

为探究预消化蛋白（Predigested protein）对肉鸡生长性能、免疫性能和肠道形态学的影响,探讨应用预消化蛋白制备低蛋白日粮的可行性,将180只1日龄肉鸡分为5组,每组4个重复,每个重复9只鸡,分别为对照组（普通玉米-豆粕型）、预消化蛋白组（5%预消化蛋白替代去皮豆粕）、低蛋白1组（预消化蛋白组降低0.5%蛋白）、低蛋白2组（预消化蛋白组降低1.0%蛋白）、低蛋白3组（预消化蛋白组降低1.5%蛋白）。试验期42 d,观察、检测各组肉鸡生长性能、肠道形态、免疫指标。结果显示：与对照组相比,1～21日龄预消化蛋白组的平均日增重显著升高（P<0.05）,预消化蛋白组的料重比显著降低（P<0.05）;22～42日龄预消化蛋白组、低蛋白1、2组的平均日采食量显著降低（P<0.05）,平均日增重显著升高（P<0.05）;22～42日龄预消化蛋白组、低蛋白1、2、3组的料重比均显著降低（P<0.05）;1～42日龄预消化蛋白组、低蛋白1、2组的平均日采食量均显著降低（P<0.05）,预消化蛋白组、低蛋白1、2组的平均日增重均显著升高（P<0.05）...     

纳米氧化锌对小鼠免疫功能的影响

探讨纳米氧化锌的免疫调节作用。设3个试验组和1个空白对照组。采用小鼠内脏体质量比、ConA诱导的小鼠淋巴细胞转化试验(MTT法)、碳廓清试验、白蛋白(AL)含量测定、血清溶血素试验和巨噬细胞吞噬功能的测定等一系列方法。结果表明,日粮中添加40～80mg/kg纳米氧化锌,尤其是60mg/kg纳米氧化锌对小鼠体质量、脏器质量比、淋巴细胞转化功能、碳廓清指数、吞噬指数和血清抗体水平均有显著提高作用。因此,纳米氧化锌具有很好的免疫调节作用。     

艾叶复方制剂对小鼠免疫功能的影响

艾叶复方制剂是由天然中草药和维生素及微量元素构成的复方制剂，主要由艾叶水提取物、甘草、维生素A、纳米氧化锌等组成，具有平喘镇咳、祛痰、促进上皮组织再生和保护其完整性、提高机体免疫力等功效。为了进一步探讨艾叶复方制剂扶正固本的作用机制，本文根据保健品免疫学功能评价程序，探讨了艾叶复方制剂对小鼠免疫功能的影响，以便为艾叶复方制剂的应用提供一定的理论依据。     

仔猪白痢散对小鼠免疫功能的影响

仔猪白痢散对小鼠免疫功能的影响彭远羲，王豪举，冯昌荣，刘华英，吕寿英，虞纯方（西南农业大学动物养殖学院，四川重庆６３０７１６）临床研究表明，仔猪白痢散，可增强仔猪抗病能力，对仔猪白痢、黄痢等疾病有很好的治疗效果￣［１］。在此基础上，我们研究了该制剂对...     

猫松果腺提取物对小鼠免疫功能的影响

连续注射猫松果腺提取物（MSTQW），观察其对免疫缺陷小鼠免疫功能的影响，结果表明，MSTQW对免疫器官肝、脾、胸腺的增重作用明显（P＜0．01），能增强小鼠抗疲劳能力（P＜0.01)；淋巴细胞比例升高P＜0.01)。提示 出MSTQW对免疫缺陷小鼠的整体免疫功能具有显著的恢复作用。     

孕母康对小鼠免疫功能的影响

本文研究了中药制剂学孕母康对小鼠免疫功能的影响。结果表明,孕母康能增加小鼠脾脏和胸腺的重量;增强腹腔巨噬细胞吞噬百分率及吞噬指数。     

黑木耳多糖对小鼠免疫功能的影响

从黑木耳中提取多糖,研究其对小鼠免疫功能的影响。通过灌胃的方法检测不同剂量黑木耳多糖对小鼠免疫器官发育、溶血素生成和巨噬细胞吞噬功能的影响。结果显示,黑木耳多糖可明显提高小鼠脾脏和胸腺指数,促进脾脏及胸腺的发育,促进巨噬细胞的吞噬活性,明显增强小鼠的体液免疫功能。研究表明黑木耳多糖具有明显的增强小鼠免疫功能的作用。     

芦笋对小鼠免疫功能的增强作用

给小鼠连续(7～14天)灌服不同剂量的芦笋液(1.5,3.0,3.5,7.5及15g/kg 体重),发现能使正常小鼠脾指数增加40～90%,抗体分泌细胞(PFC)活性增加22%,Ea-RFC%、Ea-ANAE%均有不同程度的增加。芦笋可使被环磷酰胺抑制的腹腔巨噬细胞(Mφ)吞噬功能恢复 50～120%。同时发现,其高剂量对免疫功能有抑制作用,最佳剂量为3.5g/kg 体重。实验结果表明,芦笋是一种良好的免疫调节剂。     

病毒糖基化作用对免疫应答的影响

病毒蛋白糖基化较为常见,但糖基化的类型各不相同。病毒的糖基化蛋白具有识别宿主细胞,介导病毒囊膜与宿主细胞融合以及引起病毒免疫逃避现象等多种生物学特性。人类免疫缺陷病毒的GP41与猪呼吸与繁殖综合征病毒GP5蛋白上存在诱骗表位,诱骗表位抑制临近中和表位的识别。GP5蛋白膜外区上非中和表位A表位会降低临近中和表位B表位的免疫原性,使针对B表位中和抗体延缓产生。除了两个表位位置临近外,寡糖链对B表位的遮蔽或许是造成该现象的主要因素。本文就糖基化的类型,病毒糖基化蛋白的生物学特性以及与糖基化作用相关的猪繁殖与呼吸综合征病毒GP5蛋白诱骗表位进行了介绍以期阐明糖基化作用与免疫应答现象之间的联系。     

The influence of dietary protein content on the performance of genetically lean or fat growing chickens

Genetically lean or fat male chickens were fed from 3 to 8 weeks of age on four diets of different protein content: 152, 172, 191 or 211 g/kg. The two lower protein contents depressed growth of lean chickens but had no adverse effects on fat chickens. In both lines increasing dietary protein decreased food: gain ratio and abdominal fat desposition relative to live body weight. Protein deposited and the efficiency of utilisation of dietary protein were higher in all instances in lean birds.     

The influence of environment on development of the mucosal immune system

The mucosal immune system expresses active responses against pathogens and also tolerance against harmless food and commensal bacterial antigens. The mechanisms that determine which of these outcomes occur after recognition of antigens by T-cells are not clear. One possibility is that it is determined by the initial interaction between a dendritic and a na?ve T-cell in organised lymphoid tissue. However, such organised structures are, evolutionarily, quite recent and the original immune system must have made appropriate responses in more diffuse immunological architecture; a second possibility is that the critical interaction is between primed T-cells and their environment, in the lamina propria of the intestine. The mucosal immune system of neonates is poorly developed and inefficient at expressing appropriate immune responses. Development is influenced by a range of environmental factors including maternally derived antigen or antibody and commensal flora and pathogens. The intestine is a complex immunological structure in which the immune system and the macro- and microenvironment interact.     

冷应激环境下补充Vc对雄性小鼠免疫器官和呼吸器官组织结构的影响

选用清洁级雄性昆明小鼠30只，随机分均为冷应激组、冷应激＋Vc组和对照组，冷应激和冷应激＋Vc组每天在0℃、下给2h的冷刺激，冷应激＋Vc纽补充300μg／g的Vc，试验期1周。结果，在冷应激环境中，小鼠早晚体质量均表现明显下降趋势，胸腺、脾脏和肺脏的重量均显著降低（P〈0．05），器官指数有所下降，但差异不显著（P〉0．05）；胸腺小体数量增加，胸腺细胞数量明显减少，动脉周围淋巴鞘变薄，肺泡腔变大，肺泡壁变薄，肺泡间毛细血管减少。补充Vc后，小鼠早晚体质量下降趋势减缓，肺脏重量和器官指数显著增加（P〈0．05），胸腺和脾脏重量及器官指数也有所增加，但差异不显著（P〉0．05）。胸腺小体体积减小，淋巴细胞数量有所增加，脾小结数量以及体积都有所增加，动脉周围淋巴鞘增厚，肺泡壁明显增厚，肺泡间结缔组织增加，毛细血管增多。结果表明补充Vc可以改善冷应激对免疫器官和呼吸器官造成的不良影响。     

植物提取物对猪生产性能的影响

植物提取物添加剂作为一种天然、多功能性、无毒副作用、无抗药性的新兴＂绿色添加剂＂,对于保护环境、促进畜牧业的可持续发展意义重大。本文就植物提取物的主要有效成分和功能,以及植物提取物对猪生产性能的影响进行了综述,为开发利用植物提取物提供理论依据。     

热应激对家禽生产性能的影响

随着全球气候温室效应的不断加剧及高度集约化畜牧生产的发展,环境应激对家禽的危害日益严重。在多种应激因子中,高温对家禽的不良影响更为突出,本文简述热应激对家禽的影响。１采食量 一般认为,环境温度高于等热区,每升高１℃,采食量减少１．４％～１．６％。由于鸡的年龄、品种、生理状况、饲料营养水平及热应激的刺激强度、持续时间不同,高温对采食量的影响幅度不尽相同。Ｖｏ报道白莱航鸡自２周龄到３２周龄饲养于２１．１℃和３５℃环境中,最后１周高温组鸡的采食量只有适温鸡的５０％。Ｃｈａｒｌｅｓ等发现４９日龄以前的肉…     

The effect of cadmium chloride on the immune response in mice.

Six week old BDF1 female mice were exposed to cadmium chloride in the drinking water at concentrations ranging from 0 to 50 micrograms/mL cadmium for three weeks. The humoral immune response against sheep red blood cells which is T-lymphocyte and macrophage dependent, was suppressed in a dose dependent fashion with the maximum suppression of 28.2% observed in the highest exposure group (P less than 0.0001). Mitogen studies demonstrated that cadmium was a weak mitogen, producing a dose-dependent enhancement of blastogenesis (P = 0.026). T-lymphocyte responses which were induced by concanavalin A were not affected by cadmium exposure (P = 0.284). A dose-dependent enhancement of the B-lymphocyte activity was produced in the presence of cadmium when the lymphocytes were induced with Escherichia coli, lipopolysaccharide, a B-lymphocyte mitogen (P = 0.007). These results suggest that the immunosuppressive effects of cadmium associated with the humoral immune response are not due to an impairment of lymphocyte proliferation, an intermediate step involved in the generation of an immune response. The immunosuppressive effects were produced at relatively low cadmium exposures as indicated by the renal cadmium concentrations suggesting that the immune systems is very vulnerable to the toxic effects of cadmium.     

The influence of prepartal bacteriuria on the reproductive performance of the sow

In a Slowakian indoor pig production unit, with high prevalence of vaginal-vulval discharges, the sows were subjected one day prefarrowing to urine analysis. Sows suffering urinary tract infection (UTI) were assigned to an UTI group (group 1, n = 384), the remaining sows were classified as free of UTI and were assigned to group 2 (n = 1099). Total born litter size, liveborn litter size, weaning litter size and the occurrence of periparturient diseases, reasons for sow cullings at weaning, subsequent weaning to estrus intervals, conceptions- and farrowing rate, next total born- and lifeborn litter size and the occurrence of periparturient diseases were evaluated. UTI having sows had smaller (p < 0.05) total born litter size (11.71 +/- 1.11) when compared to the healthy animals (12.97 +/- 1.25). Liveborn litter size was significantly (p < 0.01) lower in group 1 (10.21 +/- 0.81 vs. group 2: 11.31 +/- 1.21). The occurrence of periparturient diseases revealed highly significant (p < 0.001) differences between the groups (group one 26.24% vs. group two 4.64%). Weaning litter size showed significant (p < 0.05) differences between group 1 (9.21 +/- 1.02) and 2 (10.11 +/- 0.37). More (p < 0.05) sows were culled post-weaning in the UTI group, compared to the healthy animals. Causes of post-weaning cullings differed between the groups: all sows of the group one had the pathological signs of swine urogenital disease at culling, while the majority of sows of the group 2 were culled due to locomotor problems and chronic mastitis. Subsequent weaning to estrus intervals, conceptions-, and farrowing rate and next total born litter size differed significantly (p < 0.05) between the groups, next lifeborn litter size (p < 0.01) and the occurrence of periparturient diseases (p < 0.001) were high significantly better in the healthy than in the UTI suffering group of sows. Implications: antepartal UTI might be the sign of swine urogenital disease and might negatively influence the sows reproductive performance.     

Influences of lipopolysaccharide-induced immune challenge on performance and whole-body protein turnover in weanling pigs

The objective of this study is to characterize the influence of immune stress induced by lipopolysaccharide (LPS) on protein utilization and turnover for early-weaned pigs. A total of 15, crossbred weanling pigs (initial body weight 10.15 ± 0.39 kg) were assigned to one of three treatments. Pigs were injected with LPS and fed ad libitum (LPS-challenge), or injected with endotoxin-free physiological salt solution (PSS) and fed ad libitum (control), or injected with PSS and fed the same amount of feed as LPS-challenged pigs (pair-feed). All pigs received a 4-d nitrogen balance trial. On d 1 and 3 of the trial, LPS-challenged pigs were injected intramuscularly with 200 μg/kg BW of LPS dissolved in 1 ml PSS. Pigs in other treatments were injected with 1 ml PSS. ¹⁵N-Glycine (5 mg/kg BW) was gastrically infused after the second injection. Feces and urine were collected daily to determine the N output throughout the duration of the trial. Lymphocyte blastogenesis (LB) and serum immunoglobulins (IgA, IgG, IgM) were also detected to illustrate the LPS-induced immune responses. Results indicated that the injection of LPS significantly (P < 0.01) elevated the LB and resulted in lower average daily gain (ADG), feed intake (ADFI) and efficiency of feed utilization than control pigs. Pair-fed pigs had higher performance than LPS-challenged pig but poorer than control pigs. Injection of LPS also resulted in significantly (P < 0.01) lower nitrogen intake and efficiency of utilization than controls, and more fecal N excretion than Pair-fed pigs (3.19 ± 0.85 vs. 2.19 ± 0.67 g/d, P < 0.05). The whole-body nitrogen flux (4.34 ± 0.19 vs. 11.35 ± 0.12 g N/kg BW^0.75/d) and N accretion (5.57 ± 0.59 vs. 10.17 ± 1.12 g Pr/kg BW^0.75/d) were acutely (P < 0.01) reduced as the feed intake decreased, but there was no significant difference between LPS-challenged and pair-fed pigs. Injection of LPS markedly (P < 0.05) increased the protein degradation (16.76 ± 1.09 vs. 14.53 ± 1.24 g N/kg BW^0.75/d). It is concluded that LPS-induced immune challenge depresses growth performance and feed utilization efficiency by enhancing protein degradation rate and decreasing protein utilization for body protein retention.