免疫程序及疫苗质量的不同对口蹄疫、猪瘟免疫效果的影响试验

口蹄疫、猪瘟同步免疫对抗体的产生没有影响。在免疫中疫苗的质量与抗体的产生呈正相关，猪瘟脾淋苗明显优于猪瘟细胞苗，口蹄疫浓缩苗优于普通苗。口蹄疫、猪瘟一次免疫都不能达到免疫保护要求，两次免疫优于一次免疫。     

浅析鸡群免疫失败的原因

鸡群免疫是预防鸡群发生传染病的生重要技术环节。但在实践中,由于种种原因,导致鸡群免疫失败,给养鸡业主造成很大的经济损失。主要原因有疫苗质量差、疫苗保存和运输不当、免疫程序不合理、鸡群健康状况差。现结合工作实践,对上述各方面逐一浅析,并提出相应对策。     

浅谈动物的免疫程序

在日益发展的大型工业化饲养畜禽的情况下,兽医科技人员在制定动物传染病防疫计划时,免疫程序设计的是否合适是直接影响动物防疫效果的一个重要因素。所谓免疫程序是指免疫接种之前,事先编排的先后次序。其内容包括:免疫接种不同生物制品的种类,接种时期,被接种动物的日龄、接种方法、间隔期及联合苗接种等项。在欧美的一些国家非常重视动物免疫程序的设计,有专题研究。我国对此尚注意不多,有待多做调查和分析,但对于全世界,全中国及至一个饲养场来     

免疫程序不规范导致猪只免疫失败

导致猪免疫失败的因素很多,有疫苗的质量问题,猪机体存在的问题,疫苗运输、保存的问题,还有免疫方法不当或免疫程序不规范都能引起免疫失败。在生产中,免疫方法不当或免疫程序不规范导致免疫失败占很大比重,现就这一现象做一分析。1免疫接种方法不正确不同品种、不同类型的疫苗     

家兔疫苗免疫程序

免疫程序不是一成不变的,要因地制宜.在不同的地区、不同的兔场、不同的季节,其兔病的流行情况是不一样的,在制订时要根据本场的疫病流行情况和特点来建立合理的免疫程序.     

谈商品蛋鸡免疫程序的科学制定

1989年正定县畜牧兽医站医生根据石家庄地区农村养鸡业几种主要疾病流行情况，研究、制定了第一套蛋鸡免疫程序，距今十几年来，随着时间的推移、养鸡业的发展以及疫病流行情况的变化，对该套免疫程序已先后修定了13次。2002年以来正定县畜牧兽医站所推行的第14套修正程序如下表：     

家兔疫苗免疫程序的探讨

通过对目前省内家兔免疫程序的调查，结果表明：大多数地区只用了兔瘟巴魏三联苗或兔瘟－巴氏杆菌病二联疫苗免疫，免疫程序不够合理。对其存在的问题，笔者作出了原因分析，并根据兔病流行的特点，提供了家兔的基础免疫程序，同时对免疫失败的原因也进行了分析总结。     

如何制定鸡场免疫程序？

答：免疫程序即根据疫病、疫苗和鸡群的特点，以及鸡场（舍）条件所制定的具体的计划免疫实施程序。制定最佳免疫程序的目的在于用最少的人力、物力，收到最理想的免疫效果，以全面提高鸡群的抗体水平，从而控制和消灭传染病。     

怎样设计肉鸡场的免疫程序

免疫程序的制定受多方面因素的影响，即使是同种疫 (菌 )苗，在不同养鸡场、各种不同饲养方式等情况下，免疫程序也不可能完全相同。因此，要达到最佳免疫效果，应根据鸡群疫病的种类、疫苗的特性、免疫有效期、肉鸡机体免疫状况等不同情况，制定切实可行的免疫程序。1 免疫程序制定依据 1.1根据疫情制定根据本鸡场、本地区疫病发生的实际情况，确定所需接种的疫苗。一般情况下，当地有该病流行或可能受威胁，而且有疫 (菌 )苗可预防的疾病应重点进行免疫接种。没有威胁或当地从未发生过的疫病可不接种。否则，不但浪费人力物力，还会使疫病…     

大型鸡场新城疫免疫程序的确定

我站从 1993年起研究大型鸡场新城疫免疫程序，通过对无锡市两个大型鸡场鸡群 HI抗体监测，确定了符合该场的最佳免疫方法和程序。 1疫苗 　　荷兰英特威公司 ND冻干疫苗 clone30；荷兰英特威公司 ND油乳剂灭活疫苗；江苏省家禽科学研究所（家禽所）Ⅳ系 (Lasota)SPF级疫苗。 2 ND抗体监测 　　不定期随机取样，取样率为 0.1％～ 0.3％，监测单位：无锡市郊区畜牧兽医站。监测方法使用常规的 HIβ－微量法。 3免疫程序及方法 (见表 1)4四批种鸡后代雏母源抗体的衰减情况 　　种鸡后代雏从一日龄开始每隔 3～ 5天随机取样检测母源抗体…     

Cellular immunity shown in pseudorabies virus-infected pigs by leukocyte migration-inhibition procedure.

Cellular immunity in pigs inoculated with pseudorabies virus (PRV) was studied by the agarose plate technique of direct leukocyte migration-inhibition procedure. Migration of leukocytes from PRV-infected pigs was inhibited in the presence of PRV antigen, whereas migration of leukocytes from nonexposed pigs was not inhibited in the presence of the same antigen. The migration of leukocytes collected 4 days after intranasal exposure to PRV was inhibited; humoral antibodies could not be detected until 7 days after exposure. Cellular immunity was present in pigs 14 days after inoculation with inactivated PRV antigens; low concentrations of neutralizing and precipitating antibodies were present at this time. The leukocyte migration-inhibiton procedure was found to be a useful tool in studying the role of cellular immunity in PRV infections.     

规模猪场猪瘟免疫失败调查及免疫程序优化

为调查规模猪场猪瘟的免疫效果,选取北京市3个规模猪场,每场随机抽取10头仔猪分别在25、60日龄和90日龄采血分离血清,检测猪瘟抗体.A、B、C3个猪场的母源抗体阳性率分别为100％,50％,0％;2次免疫后抗体阳性率分别为10％,90％,90％.由于猪场A猪瘟免疫失败,对其免疫程序进行了优化,将首免时间推迟至50日龄.优化免疫程序后2次免疫后抗体阳性率达到70％.结果表明,母源抗体阳性率直接影响猪瘟疫苗对仔猪的免疫效果,仔猪母源抗体降至50％左右进行猪瘟免疫可取得比较理想的结果.本研究为规模猪场结合仔猪母源抗体水平制定合理猪瘟免疫方案提供了较好的参考.     

虾类免疫系统及其免疫增强剂的研究

近年来我国水产养殖规模不断扩大,集约化和工厂化程度越来越高,但养殖水域污染日趋严重,导致病害的频繁发生,严重困扰着水产养殖业的健康发展.特别是对虾养殖业中的严重疾病．使中国水产业蒙受了巨大损失。以对虾养殖为例,1988年至1992年间,对虾养殖业年产值约40多亿元（不含对虾育苗产值）,年创汇5～7亿美元,     

Necropsy procedure

The purpose of this article is to provide guidelines for the necropsy of a calf with diarrhea. Figures and tables are designed to help this procedure. With proper tools and a systematic approach, the entire necropsy should take only 20 to 30 minutes. The efficient and thorough completion of a necropsy often improves the relationship between owner and veterinarian.     

疫苗与免疫(下)

4免疫方法及注意事项 4．1免疫接种方法有滴鼻、点眼、刺种、喷雾、皮下注射、肌肉注射、饮水、涂肛等方法。要采用正确的稀释和接种方法，油苗要温至室温再行注射，免得反应较大。活疫苗要现用现配，最好半天内用完，马立克氏病疫苗要在配好后1～2h内用完。     

Protective immunity against Newcastle disease: the role of cell-mediated immunity

The role of cell-mediated immunity (CMI) in protection of birds from Newcastle disease was investigated by two different strategies in which only Newcastle disease virus (NDV)-specific CMI was conveyed without neutralizing antibodies. In the first strategy, selected 3-wk-old specific-pathogen-free (SPF) birds were vaccinated with either live NDV (LNDV), ultraviolet-inactivated NDV (UVNDV), sodium dodecyl sulfate-treated NDV (SDSNDV), or phosphate-buffered saline (PBS) (negative control) by the subcutaneous route. Birds were booster vaccinated 2 wk later and challenged with the velogenic Texas GB strain of NDV 1 wk after booster. All vaccinated birds had specific CMI responses to NDV as measured by a blastogenesis microassay. NDV neutralizing (VN) and hemagglutination inhibition (HI) antibody responses were detected in birds vaccinated with LNDV and UVNDV. However, birds vaccinated with SDSNDV developed antibodies that were detected by western blot analysis but not by the VN or HI test. Protection from challenge was observed only in those birds that had VN or HI antibody response. That is, birds with demonstrable CMI and VN or HI antibody response were protected, whereas birds with demonstrable CMI but no VN or HI antibody response were not protected. In the second strategy, birds from SPF embryos were treated in ovo with cyclophosphamide (CY) to deplete immune cells. The birds were monitored and, at 2 wk of age, were selected for the presence of T-cell activity and the absence of B-cell activity. Birds that had a significant T-cell response, but not a B-cell response, were vaccinated with either LNDV, UVNDV, or PBS at 3 wk of age along with the corresponding CY-untreated control birds. The birds were booster vaccinated at 5 wk of age and were challenged with Texas GB strain of NDV at 6 wk of age. All birds vaccinated with LNDV or UVNDV had a specific CMI response to NDV, VN or HI NDV antibodies were detected in all CY-nontreated vaccinated birds and some of the CY-treated vaccinated birds that were found to have regenerated their B-cell function at 1 wk postbooster. The challenge results clearly revealed that CY-treated birds that had NDV-specific CMI and VN or HI antibody responses to LNDV or UVNDV were protected, as were the CY-nontreated vaccinated birds. However, birds that had NDV-specific CMI response but did not have VN or HI antibodies were not protected from challenge. The results from both strategies indicate that specific CMI to NDV by itself is not protective against virulent NDV challenge. The presence of VN or HI antibodies is necessary in providing protection from Newcastle disease.     

Fish immunity and parasite infections: from innate immunity to immunoprophylactic prospects

The increasing economic importance of fish parasitoses for aquaculture and fisheries has enhanced the interest in the defence mechanisms against these infections. Both innate and adaptive immune responses are mounted by fish to control parasite infections, and several mechanisms described for mammalian parasitoses have also been demonstrated in teleosts. Innate immune initiation relies on the recognition of pathogen-associated molecular patterns (PAMPs) by pathogen recognizing receptors (PRRs). A number of PRRs, mainly Toll-like receptors (TLRs), have been characterized in fish, and some molecules susceptible of functioning as PAMPs are known for some fish parasites. A lectin-carbohydrate interaction has also been described in some host fish-parasite systems, thus probably involving C-type lectin receptors. Inflammatory reactions involving cellular reactions, as phagocytosis and phagocyte activity (including oxidative mechanisms), as well as complement activity, are modulated by many fish parasites, including mainly ciliates, flagellates and myxozoans. Besides complement, a number of humoral immune factors (peroxidases, lysozyme, acute-phase proteins) are also implicated in the response to some parasites. Among adaptive responses, most data deal with the presence of B lymphocytes and the production of specific antibodies (Abs). Although an increasing number of T-cell markers have been described for teleosts, the specific characterization of those involved in their response is far from being obtained. Gene expression studies have demonstrated the involvement of other mediators of the innate and adaptive responses, i.e., cytokines [interleukins (IL-1, IL-8), tumor necrosis factor (TNF), interferon (IFN)], chemokines (CXC, CC), as well as several oxidative enzymes [inducible nitric oxide synthase (iNOS), cyclo-oxygenase 2 (COX-2)]. Information is scarcer for factors more directly linked to adaptive responses, such as major histocompatibility (MH) receptors, T cell receptors (TCRs) and IgM. Expression of some immune genes varied according to the phase of infection, and proinflammatory cytokines were mainly activated in the early stages. Gene expression was generally higher in the target tissues for some skin and gill parasites, as Ichthyophthirius multifiliis, Neoparamoeba spp. and Lepeophtheirus salmonis, thus confirming the relevance of mucosal immunity in these infections. The existence of protective responses has been demonstrated for several fish parasites, both in natural infections and in immunization studies. Most information on the mechanisms involved in protection deals with the production of specific Abs. Nevertheless, their levels are not always correlated to protection, and the precise involvement of immune mechanisms in the response is unknown in many cases. No commercial vaccine is currently available for piscine parasitoses, although experimental vaccines have been assayed against I. multifiliis, Cryptobia salmositica and scuticociliates. The known information points to the need for integrated studies of the mechanisms involved in protection, in order to choose the optimum antigen candidates, adjuvants and formulations.