Potency tests for commercial oil-adjuvanted foot-and-mouth disease (FMD) vaccines are usually carried out in cattle, using a full dose (2 ml) of vaccine and homologous virus challenge. However, in sheep the recommended vaccine dose is half of the cattle dose (1 ml) and most vaccines have not been potency tested for this species, especially with heterologous viruses. To determine the efficacy of a high potency (>6PD₅₀) FMD virus (FMDV) O1Manisa vaccine in sheep, we carried out a study using a heterologous FMDV (FMDV O/SKR/2010 - Mya-98 strain) challenge. Groups of seven animals each were vaccinated with 2×, 1×, 1/2× or 1/4× dose (2 ml, 1 ml, 0.5 ml or 0.25 ml respectively) and challenged at 7 days post vaccination (dpv). Only 3 of the 7 sheep in the group vaccinated with 2 ml were protected. With 2 additional groups, receiving double or single doses and challenged at 14 dpv, 4 of 7 sheep were protected in each group. None of the sheep had measurable neutralising antibodies against the vaccine or challenge virus at 7 dpv. However, all vaccinated animals challenged at 14 dpv had a homologous neutralising response against FMDV O1 Manisa on the day of challenge and all but one animal also had a heterologous response to FMDV O/SKR/2010. Infectious FMDV and viral RNA could be found in nasal swabs between 1 and 6 days post challenge (dpc) in most vaccinated sheep, but those vaccinated with higher doses or challenged at 14 dpv showed significant decreases in the level of FMDV detection. Intermittent virus shedding was noticed between 1 and 35 dpc in all vaccinated groups, but persistent infection could be demonstrated only in 4 sheep (20%). This study showed that at the recommended dose, a high potency (>6 PD₅₀) FMDV O1Manisa vaccine does not protect sheep against a heterologous challenge at 7 dpv. However, partial protection was observed when a double dose was used at 7 dpv or when double or single dose vaccinated sheep were challenged at 14 dpv.

商业用油佐剂性口蹄疫（FMD）疫苗的效力测试通常在牛中进行，使用全剂量（2 ml）疫苗和同源病毒攻击。但是，在绵羊中，推荐的疫苗剂量是牛的一半（1 ml），并且大多数疫苗尚未针对该物种进行功效测试，尤其是异源病毒。确定高效能的功效（> 6PD ₅₀）绵羊FMD病毒（FMDV）O1Manisa疫苗，我们使用异源FMDV（FMDV O / SKR / 2010-Mya-98株）进行了研究。分别对7只动物进行2倍，1倍，1/2倍或1/4倍剂量（分别为2毫升，1毫升，0.5毫升或0.25毫升）的疫苗接种，并在接种后7天进行攻击（dpv）。接种2 ml疫苗的7只绵羊中只有3只受到保护。另外有两组，分别接受双剂量或单剂量并以14 dpv的剂量攻击，每组7只绵羊中有4只受到保护。在7 dpv时，所有绵羊均没有针对疫苗或攻击病毒的可测量中和抗体。但是，所有在14 dpv攻击的疫苗接种动物在攻击当天均对FMDV O1 Manisa具有同源中和反应，除一只动物外，所有动物均对FMDV O / SKR / 2010也具有异源反应。在大多数接种疫苗的绵羊中，攻击后（dpc）1至6天之间的鼻拭子中可发现传染性FMDV和病毒RNA，但接种更高剂量或以14 dpv攻击的绵羊，其FMDV检测水平显着降低。在所有接种组中，发现病毒在1至35 dpc之间出现间歇性脱落，但仅4只绵羊（20％）表现出持续感染。这项研究表明，在推荐剂量下，药效较高（> 6 PD 但是只有4只绵羊（20％）可以证明持续感染。这项研究表明，在推荐剂量下，药效较高（> 6 PD 但是只有4只绵羊（20％）可以证明持续感染。这项研究表明，在推荐剂量下，药效较高（> 6 PD₅₀）FMDV O1Manisa疫苗不能保护绵羊免受7 dpv的异源攻击。但是，当在7 dpv使用双剂量或在14 dpv接种双剂量或单剂量接种的绵羊时，观察到部分保护。