Riising H-J, Murmans M, Witvliet M
Intervet Danmark A/S, Skovlunde, Denmark.
J Vet Med B Infect Dis Vet Public Health. 2005 Aug;52(6):296-300. doi: 10.1111/j.1439-0450.2005.00857.x.
The efficacy of a new vaccine against neonatal Escherichia coli diarrhoea in piglets containing purified F4ab, F4ac, F5 and F6 fimbriae and detoxified heat-labile toxin (LT) was tested in challenge experiments by the method described by the European Pharmacopoeia (3rd edn, EDQM, Council of Europe, Strasbourg, France). A group of 11 young sows from a herd without E. coli problems was vaccinated 6-8 and 2-4 weeks prior to expected farrowing and another group of nine young sows were non-vaccinated controls. Escherichia coli antibody titres were determined in serum samples taken from the sows before first vaccination and before farrowing and in colostrum samples. The newborn piglets were allowed to suckle colostrum from their mother immediately after birth. The piglets were marked with individually numbered ear tags. Approximately 12 h after birth, 118 piglets from vaccinated sows and 79 piglets from non-vaccinated control sows were challenged by oral instillation of 5 ml of a freshly prepared culture of one of the challenge strains [O8:K87:F4ab (LT+) or O149:K91:F4ac (LT+) or O9:K30:F5 or O9:K103:F6 respectively]. The challenge cultures contained as a mean 6.8x10(9) CFU/ml. After challenge the piglets were observed for 7 days and mortality and morbidity were recorded. Vaccinated sows developed significant levels of antibody titres in colostrum and serum. Control sows stayed at a low/seronegative level. The protective efficacy was excellent because 66.7-87.5% of the piglets from vaccinated sows remained without clinical signs after challenge. Only 0.0-28.0% of the piglets from non-vaccinated sows remained healthy and more than 47.1% of the piglets in this group died after challenge. It is concluded that the new vaccine is very effective in protection of piglets against neonatal E. coli diarrhoea.
采用欧洲药典（第3版，欧洲药品质量管理局，欧洲理事会，法国斯特拉斯堡）所述方法，通过攻毒实验对一种新型疫苗的效力进行了测试，该疫苗含有纯化的F4ab、F4ac、F5和F6菌毛以及解毒的不耐热毒素（LT），用于预防仔猪的新生仔猪大肠杆菌腹泻。从一个不存在大肠杆菌问题的猪群中选取11头年轻母猪，在预计分娩前6 - 8周和2 - 4周进行疫苗接种，另一组9头年轻母猪作为未接种疫苗的对照。在首次接种疫苗前、分娩前从母猪采集的血清样本以及初乳样本中测定大肠杆菌抗体滴度。新生仔猪出生后立即让其吸食母乳。仔猪用单独编号的耳标进行标记。出生后约12小时，对118头来自接种疫苗母猪的仔猪和79头来自未接种疫苗对照母猪的仔猪分别经口灌胃5 ml新鲜制备的其中一种攻毒菌株培养物[分别为O8:K87:F4ab（LT+）或O149:K91:F4ac（LT+）或O9:K30:F5或O9:K103:F6]进行攻毒。攻毒培养物平均含有6.8×10⁹ CFU/ml。攻毒后对仔猪观察7天，记录死亡率和发病率。接种疫苗的母猪在初乳和血清中产生了显著水平的抗体滴度。对照母猪维持在低/血清阴性水平。保护效力极佳，因为接种疫苗母猪的仔猪在攻毒后66.7 - 87.5%未出现临床症状。未接种疫苗母猪的仔猪只有0.0 - 28.0%保持健康，该组超过47.1%的仔猪在攻毒后死亡。结论是，这种新型疫苗在保护仔猪免受新生仔猪大肠杆菌腹泻方面非常有效。
