猪支原体肺炎活疫苗(RM48株)的最小免疫剂量测定及活菌滴度与免疫保护率平行关系试验

The minimum immune dose measure of Mycoplasma hyopneumoniae Live vaccine (RM48 strain) and the parallel assay of vaccine CCU titer and potency

关键词:  猪肺炎支原体,活疫苗  最小免疫计量  平行关系

Key words:  Mycoplasma hyopneumoniae  live vaccine  minimum immune dose  viable bacteria title  immune protection rate  parallel.

摘要:

为了确定猪支原体肺炎活疫苗(RM48株)的最小免疫计量,本研究使用了2批该疫苗(活菌滴度均为10₈CCU/ml),将其分别用原倍、10倍、100倍和1000倍稀释,以胸腔注射和鼻腔接种两种方式各免疫4头仔猪,45日后攻毒,70日后剖杀观察结果。结果表明1批疫苗的4个稀释度的胸腔注射组攻毒保护率分别为78%、77.6%、68.8%和55.2%,鼻腔接种组分别为70.6%、68.1%、58.4%和18.4%；另一批的胸腔注射组的攻毒保护率分别为80.6%、78.8%、67.6%和52.4%,鼻腔接种组分别为71.6%、68.1%、53.5%和28.4%。按照判定标准,可将该疫苗的胸腔接种最小免疫剂量确定为10₆CCU/头,鼻腔接种最小免疫剂量确定10₇CCU/头,同时结果也证明免疫保护率与活菌滴度间具有很好的平行关系。

Abstract:

In order to determine the minimum immune dose of the Mycoplasma hyopneumoniae live vaccine (RM48 strain),2 batchs of the vaccine (titer = 10₈CCU/ml) were used to inoculated piglets with two methods,include the pleural cavity injection and intranasal inoculation,after diluted to 10₈CCU/ml, 10₇CCU/ml, 10₆CCU/ml and 10₅CCU/ml.45 days later,the piglets were charged with Mycoplasma hyopneumoniae virulent strain, and autopsied for lung damage evaluation at the 70th day after the immunization. The results shows the immune efficacy the four dilutions of one batch were 78%、77.6%、68.8% and 55.2% with pleural cavity injection, 70.6%、68.1%、58.4%和18.4% with intranasal inoculation; for the other batch of vaccine,the the immune efficacy were 80.6%、78.8%、67.6%和52.4% with pleural cavity injection, 71.6%、68.1%、53.5%和28.4% with intranasal inoculation, which indicated that minimum immune dose of the vaccine is 10₆CCU/piglet by pleural inoculation and the 10₇CCU/ piglet by intranasal inoculation, and the live bacteria titer is parallel with the vaccine efficacy well.