Wilsmore A J, Wilsmore B C, Dagnall G J, Izzard K A, Woodland R M, Dawson M, Venables C
Royal Veterinary College, Boltons Park, Potters Bar, Herts.
Br Vet J. 1990 Jul-Aug;146(4):341-8. doi: 10.1016/s0007-1935(11)80027-8.
The protection afforded by an experimental, killed, adjuvanted vaccine derived from the A22 strain of Chlamydia psittaci (ovis) against ovine enzootic abortion was studied. The vaccine was used undiluted (group A), at a dilution of 10(-3) (group B) and at a dilution of 10(-6) (group C). A fourth control group (group D) was inoculated with all components of the vaccine except the chlamydial antigen. A group of rams (group R) was also vaccinated with the chlamydial antigen diluted to 10(-3). Animals were challenged 70 days after mating with the A22 strain of C. psittaci (ovis) and were studied throughout pregnancy and the subsequent lambing period. Their cell-mediated immune responses were examined using a skin test and their humoral immune responses were studied using an ELISA. Tests for excretion of chlamydiae in their faeces and genital tract during pregnancy and after parturition and in the faeces of their lambs were made. The reproductive performance of the ewes was assessed by calculating the average weight of lambs produced per ewe in each group. The experimental vaccine protected the ewes in groups A and B against challenge with C. psittaci (ovis) as none showed clinical signs of OEA or excreted chlamydiae. The average weight of lambs produced per ewe in both groups was greater than 4 kg. Both groups seroconverted after vaccination but not all of them were positive to the skin test. The experimental vaccine at 10(-6) dilution of antigen did not protect the ewes as three of 10 ewes displayed clinical OEA and excreted chlamydiae in the products of parturition.(ABSTRACT TRUNCATED AT 250 WORDS)
对一种源自鹦鹉热衣原体（羊型）A22菌株的实验性灭活佐剂疫苗预防绵羊地方性流产的效果进行了研究。疫苗未稀释使用（A组）、以10⁻³稀释度使用（B组）和以10⁻⁶稀释度使用（C组）。第四个对照组（D组）接种了除衣原体抗原外的疫苗所有成分。一组公羊（R组）也用稀释至10⁻³的衣原体抗原进行了接种。动物在配种后70天用鹦鹉热衣原体（羊型）A22菌株进行攻毒，并在整个妊娠期和随后的产羔期进行观察。通过皮肤试验检测其细胞介导免疫反应，并用ELISA研究其体液免疫反应。对妊娠期间、分娩后母羊粪便和生殖道中衣原体的排泄情况以及羔羊粪便中的衣原体进行了检测。通过计算每组每只母羊所产羔羊的平均体重来评估母羊的繁殖性能。实验疫苗保护了A组和B组的母羊免受鹦鹉热衣原体（羊型）的攻毒，因为没有一只母羊表现出地方性流产的临床症状或排泄衣原体。两组中每只母羊所产羔羊的平均体重均超过4千克。两组在接种疫苗后均发生血清转化，但并非所有母羊对皮肤试验呈阳性。抗原稀释度为10⁻⁶的实验疫苗未能保护母羊，因为10只母羊中有3只表现出地方性流产的临床症状，并在分娩产物中排泄衣原体。（摘要截短于250字）
