Epidemiological Investigation Of Haemophilus Parasuis And Porcine Type 2 Streptococcus In Some Areas Of Sichuan And Preliminary Development Of Its Two Propolis Inactivated Vaccines

In this study, we collected serum in pig farms in which pigs were affected by respiratory symptoms in Sichuan Province(Haemophilus parasuis and Streptococcus vaccine immune free) and aims to survey the infection status of the wide spread of Haemophilus parasuis disease and Streptococcal disease has a strong impact on the development of pig industry in our country.It can provide scientific basis for prevention and restriction of Haemophilus parasuis disease and streptococcal disease.Screened strain of Haemophilus parasuis and Streptococcus suis serotype 2 and preparation and made testing of Haemophilus parasuis serotype 5 and Streptococcus suis serotype 2 duplex propolis inactivated vaccine. The results are as follows:1. Haemophilus parasuis and Streptococcus suis serotype 2 seroprevalence InvestigationThis study applied ELISA kits to have antibody detection on 180 parts swine serums gathered from Sichuan Province in February 2015 to January 2016. Among which, Haemophilus parasuis antibody positive rate was 55.6%(100/180), there was a high inflection rate in places like:Xichang, Mianyang, Chengdu and Meishan, the respective rates were:85.7%(6/7),83.0%(44/53), 77.8%(14/18),66.7%(4/6). Streptococcus suis positive serum 53 parts, Streptococcus suis antibody positive rate was 29.4%(53/180), there was a high inflection rate in places like:Aba, Ya’an and Yibin, the respective rates were 54.2%(13/24),50%(4/8),48.7%(19/39). Haemophilus parasuis and Streptococcus mixed infection rate was 17.2%(31/180). It shows that the infection of Haemophilus parasuis and Streptococcus suis serotype 2 in Sichuan province is more obvious.2. Screening of vaccine strainsAccording to virulence screening and immunogenicity testing of Haemophilus parasuis serotype 5 and Streptococcus suis serotype 2 strains, we determined the vaccine strains and numbered as Hps82 and Ss903.3. Haemophilus parasuis type 5 and Streptococcus suis serotype 2 duplex propolis inactivated vaccine Preliminary Study of Preparation.The formaldehyde concentration of Hps82 and Ss903 Vaccines was 0.1%, after completely inactivation in 24h,. the amount of Hps82 bacteriab was 4.0×109CFU/ml, the amount of Ss903 bacteria was 2.0×109CFU/ml in Haemophilus parasuis type 5 and Streptococcus suis serotype 2 duplex propolis inactivated vaccine. The best immune way for was subcutaneous, secondary immunization(one week after first immunization) could produce good immunity. Vaccines saved at 4℃ after 3months still have good protection for mice. 4. Haemophilus parasuis type 5 and Streptococcus suis serotype 2 duplex propolis inactivated vaccine comparison with the commercial vaccineHaemophilus parasuis and Streptococcus suis serotype 2 duplex inactivated vaccine were compared with saled Haemophilus parasuis vaccine(Chinese animal husbandry Biological Technology company, Ltd.) and Streptococcus vaccine(Guangdong winshun Biological Pharmaceutical company, Ltd.). The results showed that Three kinds of vaccine could produce a good immune protection. Haemophilus parasuis type 5 and Streptococcus suis serotype Duplex propolis inactivated vaccine could reduce stress response of immune times.