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仔猪可通过母猪的乳汁获得母源抗体。而且母源抗体在仔猪体内具有一定的持续时间和消长规律。母源抗体可使仔猪在一定时间内被动地获得免疫保护,也可对疫苗接种后机体的主动免疫应答产生干扰。合理利用仔猪依靠母源抗体所获得的免疫保护．科学制定母猪和仔猪的免疫程序,对仔猪的疾病防治至关重要。简要阐述母源抗体的传递方式、作用和消长规律,以及母源抗体在仔猪疾病防制方面的研究和应用等。 相似文献
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刚出生仔猪可通过母乳获得母源抗体,从而得到被动的免疫保护,但这种保护能维持多久？何时接种疫苗既不受母源抗体太大的干扰又能在被动免疫保护消失前产生足够的主动免疫保护？故确定仔猪首免日龄显得尤为重要。要确定仔猪首免日龄,首先需弄清楚仔猪群的母源抗体消长规律,虽然各种疫病母源抗体的消长都已有很多试验和资料可查,但是受多种因素影响,仔猪群母源抗体的消长也不同,所以只有检测出自家猪场猪群母源抗体的消长规律,才能制定出适合自家猪场仔猪的免疫程序。 相似文献
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猪瘟免疫失败的原因分析 总被引：4，自引：0，他引：4
猪瘟是猪的一种高度传染性和致死性疫病,其特征为高热稽留,小肠管壁变性引起广泛出血、梗塞和坏死等变化。由于本病具有高度传染性,且发病率和死亡率高,而受到动物防疫部门及广大养殖场(户)的高度重视。本病通常采取疫苗免疫的方法进行控制,但在生产实践中,经常会发生由于人为因素造成的免疫失败。1母源抗体存在干扰如果母猪在配种前或分娩前进行了免疫,会将母源抗体通过初乳传给仔猪,母源抗体对初生仔猪有保护作用,但也会影响仔猪的免疫效果:即母源抗体的双重性。如果对哺乳仔猪进行免疫,应采用加倍剂量。2免疫程序存在缺陷免疫程序存在缺… 相似文献
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超前免疫──猪免疫上的新技术时常发生注射过疫苗的猪在有效免疫期内仍染上猪瘟的现象。原因是免疫程序不科学。仔猪由于吸吮母猪初乳而获得的母源抗体干扰了猪瘟疫苗，可实行仔猪超前免疫，克服母源抗体干扰。超前免疫是仔猪产下后，完成擦身、断脐、剪牙、称重等接产工... 相似文献
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为给规模猪场猪伪狂犬病(PR)免疫程序制定提供参考,在贵州省某规模猪场选取3组不同母源抗体背景仔猪群,按照不同的免疫程序进行PR疫苗免疫,然后设置不同的检测时间点,采集猪血清采用ELISA方法进行gE和gB抗体跟踪检测,初步探索仔猪群免疫抗体消长规律。结果显示:在母源gE和gB抗体均为阴性背景下,1日龄初生仔猪活疫苗滴鼻免疫对免疫抗体水平没有影响,15日龄基因缺失疫苗注射免疫后,免疫抗体水平逐渐升高,45日龄基因缺失疫苗加强免疫1个月后,免疫抗体水平达到顶峰,此后逐渐下降,到120日龄时,仍有50%的有效保护率;在gE母源抗体阴性背景下,产前40 d免疫母猪,55日龄进行基因缺失疫苗注射免疫后,仔猪免疫抗体水平持续升高,90日龄时再用基因缺失疫苗加强注射免疫1次,至120日龄免疫抗体水平达到顶峰,150日龄后开始下降,到185日龄时,仍有50%的有效保护率;在母源gE抗体阳性背景下,疫苗免疫不能使仔猪产生有效的免疫保护抗体。结果表明,仔猪母源抗体背景对于仔猪免疫程序的制定具有较大影响,合理的免疫程序要结合母源抗体和免疫抗体检测结果合理制定,并要及时淘汰gE阳性种猪。 相似文献
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1 仔猪猪瘟免疫试验分析仔猪猪瘟免疫的一般程序是断奶前进行1次免疫接种 ,断奶后再接种 1次。这是由于对已接种免疫过的母猪 ,其所产仔猪体内含有母源抗体易使抗原被中和导致免疫抑制 ;而对未免疫母猪所产仔猪 ,又因其免疫系统功能不完善而致使免疫不稳定。仔猪体内的母源抗体一部分是在孕期至分娩由母体直接传给仔猪 ,更多的是仔猪通过吃初乳获得。据测定 ,一年进行过 2次免疫接种的母猪 ,所产仔猪 51～ 60日龄时 ,体内母源抗体中和试验阳性检出率达 1 0 0 % ,其中抗体效价 1 1 6以上的占 86 5%。 1年进行 1次免疫的母猪 ,所产亲代仔猪… 相似文献
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Ut V Nguyen Vesna Melkebeek Bert Devriendt Tiphanie Goetstouwers Mario Van Poucke Luc Peelman Bruno M Goddeeris Eric Cox 《Veterinary research》2015,46(1)
F4 enterotoxigenic Escherichia coli (ETEC) cause diarrhoea and mortality in piglets leading to severe economic losses. Oral immunization of piglets with F4 fimbriae induces a protective intestinal immune response evidenced by an F4-specific serum and intestinal IgA response. However, successful oral immunization of pigs with F4 fimbriae in the presence of maternal immunity has not been demonstrated yet. In the present study we aimed to evaluate the effect of maternal immunity on the induction of a systemic immune response upon oral immunization of piglets. Whereas F4-specific IgG and IgA could be induced by oral immunization of pigs without maternal antibodies and by intramuscular immunization of pigs with maternal antibodies, no such response was seen in the orally immunized animals with maternal antibodies. Since maternal antibodies can mask an antibody response, we also looked by ELIspot assays for circulating F4-specific antibody secreting cells (ASCs). Enumerating the F4-specific ASCs within the circulating peripheral blood mononuclear cells, and the number of F4-specific IgA ASCs within the circulating IgA+ B-cells revealed an F4-specific immune response in the orally immunized animals with maternal antibodies. Interestingly, results suggest a more robust IgA booster response by oral immunization of pigs with than without maternal antibodies. These results demonstrate that oral immunization of piglets with F4-specific maternal antibodies is feasible and that these maternal antibodies seem to enhance the secondary systemic immune response. Furthermore, our ELIspot assay on enriched IgA+ B-cells could be used as a screening procedure to optimize mucosal immunization protocols in pigs with maternal immunity. 相似文献
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本文比较了不同日龄和母源抗体水平的仔猪接种高致病性猪繁殖与呼吸综合征减毒疫苗（JXA1-R株）后的抗体平均值、抗体阳性率和变异系数等指标。结果表明,对于母源抗体水平和整齐度不高的猪群,15日龄和30日龄接种减毒疫苗的免疫效果相似;对于母源抗体水平和整齐度较高的猪群,采用30日龄进行减毒疫苗接种可以产生较好的效果。本研究结果为制定适合连云港地区的高致病性猪繁殖与呼吸综合征免疫程序提供了依据。 相似文献
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本试验通过研究免疫状况良好的母猪群所产仔猪母源抗体的获得方式,仔猪体内母源抗体的持续时间,仔猪不同免疫程序的免疫效果,发现初生仔猪遵守被动免疫传递规律,仔猪体内的口蹄疫抗体水平也有自己的消长规律:哺乳后3～7d抗体水平达到最高,35日龄后开始下降,63日龄左右抗体保护率已经低于60%。所以,仔猪口蹄疫疫苗首次免疫的时间应定在35日龄,49日龄还需加强一次;疫苗的剂量:首免为1头份(2mL),加强时为2头份(3mL)。 相似文献
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怀孕后期感染PRRS病毒母猪所产新生仔猪的免疫反应 总被引：5，自引：0，他引：5
将PRRS病毒BJ－4株感染怀孕后期（约90天）的抗体阴性和阳性母猪，待自然分娩后，观察新生仔猪的免疫应答。结果显示，接种PRRS病毒BJ－4的母猪没有表现出明显的临床症状，没有出现流产死产。新生仔猪浦被子前血清中PRRS病毒核酸TR－PCR检测和ELISA抗体阴性，哺乳后特异性抗体出现，5－6周母源抗体逐渐下降；20日龄猪瘟疫苗免疫后疫苗抗体维持时间短，仔猪在40日龄后进入野毒感染的危险期。RT－nested PCR检测血清中PRRS病毒核酸和易感仔猪病毒特异性抗体监测的结果提示仔猪群内可能存在水平传播。流式细胞术检测外周血淋巴细胞亚群发现CD3^ 细胞减少，CD4^ 细胞显著下降，CD8^ ，CD4^ CD8^ 和SLA－DR^ 表达细胞升高。以上结果表明在感染后病毒能够长期持续性存在，猪场内新生仔猪母源抗体逐渐下降后，通过水平传播受到感染，感染后免疫应答受到不利影响。 相似文献
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为了研究仔猪猪瘟病毒(CSFV)母源抗体的衰减规律,本研究随机选择36头待产母猪,产后采血,选择每头母猪对应的仔猪连续采血至8周龄,分离血清,通过ELISA方法检测CSFV抗体阻断率,所测结果利用EXCEL拟合指数曲线,计算分析母猪CSFV抗体水平与仔猪母源抗体衰减规律。结果显示,36头母猪中母猪抗体阻断率80%以上6头,母猪抗体阻断率70%~79%的11头,母猪抗体阻断率60%~69%的8头,母猪抗体阻断率50%~59%的5头,母猪抗体阻断率49%以下的6头。3周龄仔猪抗体阻断率整体与母猪抗体阻断率相近且高度相关,相关系数为99%。母猪抗体阻断率在80%以上时,母源抗体对所产仔猪8周龄时仍然具有保护力;母猪抗体阻断率在70%~79%时,母源抗体对所产仔猪7周龄时不再具有保护力;母猪抗体阻断率在60%~69%时,母源抗体对所产仔猪5周龄时不再具有保护力;母猪抗体阻断率在50%~59%时,母源抗体对所产仔猪4周龄时不再具有保护力;母猪抗体阻断率49%以下时,母源抗体对所产仔猪3周龄时不再具有保护力。以上结果表明仔猪母源CSFV抗体随着仔猪周龄的增加逐渐衰减,由试验得出仔猪猪瘟疫苗首免日龄的计算公式:y=1.19x-46.55(x为母猪CSFV抗体阻断率,y为首免日龄)。因此,母猪抗体阻断率在80%以上时,仔猪母源抗体在60日龄不再具有保护力,仔猪猪瘟疫苗首免为56日龄;母猪抗体阻断率在70%~79%时,母源抗体对仔猪的保护持续到50日龄,仔猪猪瘟疫苗首免为42日龄;母猪抗体阻断率在60%~69%时和50%~59%时,母源抗体对仔猪的保护持续至36日龄和29日龄,仔猪猪瘟疫苗首免分别为28日龄和21日龄。本研究中所得母猪CSFV抗体水平计算母源抗体衰减变化,为选择母猪首免日龄,提高仔猪猪瘟疫苗免疫效果提供了科学依据。 相似文献
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猪繁殖与呼吸综合征母源抗体和免疫抗体的消长规律研究 总被引：1，自引：1，他引：0
为制定科学的免疫程序,从根本上控制猪繁殖与呼吸综合征的发生,用ELISA诊断试剂盒分别对母猪、仔猪进行了母源抗体和免疫抗体检测。试验证明母猪在配种前15 d首免,怀孕2个月时二免,在下一次配种前15 d再免,如此按生产周期免疫可以抵抗猪繁殖与呼吸综合征的感染。在母猪产前1个月免疫猪繁殖与呼吸综合征灭活疫苗,所产仔猪母源抗体60日龄时为阴性,故45日龄左右对仔猪进行首免最佳,为确定仔猪首免日龄提供了理论依据。对40日龄仔猪免疫猪繁殖与呼吸综合征灭活疫苗后,仔猪58日龄时抗体S/P平均值最高,到160日龄育肥猪时抗体S/P平均值为阴性,这时不能抵抗猪繁殖与呼吸综合征的感染。对40日龄仔猪肌肉注射2 mL猪繁殖与呼吸综合征灭活疫苗,70日龄同剂量二免,85日龄时抗体S/P值平均值最高,到180日龄育肥猪时抗体S/P平均值仍为阳性,还能抵抗猪繁殖与呼吸综合征的感染,如果作为肉猪可以安全上市;作为后备母猪,在配种前进行免疫即可。非免疫母猪、仔猪对照组抗体均为阴性。通过试验基本上查明了猪繁殖与呼吸综合征母源抗体和免疫抗体的消长规律,为以后制定免疫程序提供了理论依据。 相似文献
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Per Wallgren Gran Blske Stig Gustafsson Sigbrit Mattsson Caroline Fossum 《Veterinary microbiology》1998,60(2-4):193-205
Previously healthy sows, seropositive to Mycoplasma hyopneumoniae, developed clinical signs of mycoplasmosis, as well as increasing amounts of antibodies to M. hyopneumoniae during an outbreak of the disease in a herd. During the early phase of the outbreak, young piglets (2 weeks) with maternal antibodies remained healthy while older seronegative piglets (4–7 weeks) developed the disease. The duration of the maternal antibodies to M. hyopneumoniae varied between litters and was related to the amount of antibodies in the serum of the dam. In sows, the level of serum antibodies decreased continuously from 4 weeks ante partum to partus, and the level of antibodies in the whey of colostrum was comparable to that in serum 4 weeks ante partum. After loss of maternal antibodies to M. hyopneumoniae, seropositive animals were not found among piglets younger than 9 weeks. Therefore peripheral blood mononuclear cells (PBMC) were collected from various age categories of piglets in order to measure the ability to produce antibodies to M. hyopneumoniae in vitro. PBMC obtained from piglets aged 1 and 3 weeks produced few antibodies to M. hyopneumoniae. Significantly higher levels of antibodies to M. hyopneumoniae were produced by PBMC obtained from pigs aged 5–9 weeks. Thus, the ability of PBMC to produce antibodies to M. hyopneumoniae in vitro seemed to be age-dependent. 相似文献
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Loeffen WL Heinen PP Bianchi AT Hunneman WA Verheijden JH 《Veterinary immunology and immunopathology》2003,92(1-2):23-35
The aim of this study was to determine the role of maternally derived antibodies (MDA) against an influenza H1N1 virus in the clinical protection of piglets and especially their effect on the development of the active immunity after an infection with a homologous influenza H1N1 virus. Twenty piglets with MDA and 10 piglets without MDA were housed together and inoculated twice with influenza H1N1 virus, at 7 and 15 weeks of age. Nine piglets without MDA were added to these groups at 12 weeks of age to be inoculated at 15 weeks of age only. Clinical signs, body temperature, growth performance, virus excretion, antibody responses, and influenza-specific T-cell response were monitored. It was shown that MDA protect piglets against the clinical consequences of a primary influenza infection, but that this protection is not complete. A short but significant rise in body temperature was observed and growth seemed to be inhibited due to the infection. Piglets with MDA shed virus for a longer period after an infection than piglets without MDA. Piglets with and without MDA were protected against the clinical consequences of a secondary infection. However, both after primary and secondary infection significant differences in immune responses were observed that indicated that pigs with MDA developed a weaker immunity than pigs without MDA. Furthermore, overall growth performances from weaning to slaughter show a trend in favour of pigs without maternal antibodies, compared to pigs with maternal antibodies, mainly caused by a significant better performance in the second half of the finishing period. The results of this study provide us insight in the role of MDA in clinical protection and their influence on active immunity after an influenza virus infection of pigs. Furthermore, it leads us to the discussion about the profitability of massive sow herd vaccinations in an attempt to increase MDA levels in piglets, taking into account the overall performance of these piglets and the possible effects on antigenic drift. 相似文献
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Krejci J Nechvatalova K Kudlackova H Faldyna M Kucerova Z Toman M 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2005,52(4):190-196
The objectives of the present study was to describe different dynamics of humoral immune responses to experimental infection in piglets of different stages of infection and immunity. Two groups of piglets originating from non-immune (group 1) and immune (group 2) sows at the age of 3 weeks were subdivided as follows: a half of each group of piglets was exposed to a low-dose infection with Actinobacillus pleuropneumoniae (APP) strain 9. At the age of 8 weeks, all four groups of piglets were challenged with a high infection dose of APP of the same strain. Isotype characterization of the specific antibodies in sera and in bronchoalveolar lavage fluids (BALF) to a lipopolysaccharide was carried out, besides monitoring clinical signs and post-mortem examinations. A typical primary immune response was observed in specific antibody-free piglets infected with a challenge infection. Colostrum-derived immunoglobulin-G (IgG) antibodies persisted in sera and BALF of piglets up to the age of 8 weeks. However, they did not prevent induction of specific-primary antibody response, either in 8 or 4 weeks of age, when levels of specific colostrum-derived antibodies were still high. It was demonstrated by the increase of specific IgM antibodies in sera. The infection induced an increase in the levels of IgA antibodies in BALF regardless the severity of infection and presence of specific colostrum-derived antibodies. The specific antibodies of IgG isotype increased only in BALF from piglets without colostrum-derived antibodies. 相似文献
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Vaccination with an attenuated strain of Hog cholera virus (Thiverval strain) isolated at low temperature (29°C) in tissue culture was carried out in 9–90-day piglets in a conventional herd. Vaccination of piglets free of passive antibody results in a typical primary immune response characterized by both early intense and durable antibody production and by protection against challenge. By contrast, vaccination of piglets in the presence of maternal immunity results in a variable immune status depending on the concentration of passive antibody at the time of vaccination. Results indicated that it was possible to vaccinate successfully 30–35-day piglets still passively protected by maternal immunity. 相似文献