不同NAD含量条件下培养的猪胸膜肺炎放线杆菌对小白鼠致病性和免疫保护性的影响

将在含体积分数为0.050%、0.001%的尼克酰胺腺嘌呤二核苷酸(NAD)的LB培养基中培养的血清5型猪胸膜肺炎放线杆菌(APP),分别以3×109CFU.只-1的菌量对30日龄小白鼠进行接种,观察不同NAD含量条件下培养的APP对小白鼠致病性的影响.结果表明:用0.001%NAD培养的血清5型APP对小白鼠的致病性较强,小白鼠接种APP后,多数表现肺脏严重出血;而用0.050%NAD培养的血清5型APP接种小白鼠后,只有少数小白鼠肺脏出血严重,多数表现为轻度出血.将上述条件培养的APP按常规方法制备油乳剂灭活疫苗,分别在第3周龄和第6周龄对小白鼠进行免疫接种,在2免后3周对免疫的小白鼠进行同源攻击,并对免疫前后小白鼠的抗体效价进行检测.结果表明:分别用0.050%、0.001%NAD培养的血清5型APP制备的灭活疫苗,对小白鼠的保护率差异不显著;用0.001%NAD培养的血清5型APP制备的灭活疫苗免疫小白鼠,用血清5型APP同源攻击后,发病的小白鼠肺脏出血较轻,而用0.050%NAD培养的疫苗免疫小白鼠攻毒后,发病的小白鼠肺脏出血严重.可见在不同NAD含量条件下培养的APP对小白鼠的致病性和免疫保护力不同.

The pathogenicity and immunoprotection of Actinobacillus pleuropneumoniae grown under different contents of nicotinamide ademinedinucleotide conditions on mice

30 days old mice were inoculated with Actinobacillus pleuropneumoniae(APP) serotype 5 cultured respectively on two lauria broth(LB) agar supplemented with 0.050%(volume fraction) and 0.001% nicotinamide ademine dinucleotide(NAD) at the dose of 3×109 CFU per mice.A lot of mice inoculated with APP serotype 5 grown under 0.001% NAD condition showed severe lung lesions,but few mice inoculated with APP serotype 5 grown under 0.050% NAD condition showed severe lung lesions,most of them only showed light lung lesions.The two kinds of bacteria were emulsified in an equal volume of a mineral oil adjuvant.At the age of 3 and 6 weeks,the mice were vaccinated with the vaccines.Three weeks after the second vaccination,all mice were challenged with APP serotype 5.Sera were collected before the second vaccination and before the challenge.No significant difference in the protection to mice between the two vaccines was discovered,but after vaccinated with vaccine which was made of APP serotype 5 grown under 0.001% NAD,the mice showed light lung lesions,and after vaccinated with vaccine which was made of APP serotype 5 grown under 0.050% NAD,the mice showed severe lung lesions.It is proved that the pathogenicity and immunoprotection were different when APP growed under different contents of NAD conditions.