RESEARCH ▶▶▶
Tackling Campylobacter jejuni difficult
Belgian research looked into the possibility of in ovo vaccination of broilers against Campylobacter jejuni using a bacterin and subunit vaccine. Sufficient protection was not found.
BY JASMIEN VANDEPUTTE AND OTHERS, POULTRY SCIENCE C
ampylobacter jejuni originating from poultry meat has been one of the most important causes of food- borne human bacterial gastroenteritis in the Euro- pean Union since 2005. Apart from biosecurity
measures, there are few options available for controlling Campylobacter infection in poultry. Although immunisation offers a promising method, no vaccine has yet been commer- cialised. Previously, a bacterin mix of 13 heterologeous Cam- pylobacter strains and a subunit vaccine of six conserved, im- munodominant Campylobacter antigens, induced a high and prolonged immune response in layer hens and reduced Cam- pylobacter jejuni colonisation of broilers when applied through passive immunisation. This method needed an in- feed application of antibodies obtained from the egg yolks of immunised hens. The use of fresh yolks and this method of administration are impractical to apply in the industry
setting. Therefore other administration methods need to be investigated. In ovo vaccination is a safe and user-friendly method that has already been approved for Marek’s disease, infectious bursal disease and Newcastle disease.
Earlier study not promising In ovo vaccination against Campylobacter had previously been studied with a heat killed C. jejuni isolate and with a re- combinant flagellin-based subunit vaccine with intrinsic ad- juvant activity. The results were not very promising, the same for experiments using outer membrane vesicles, although this at least resulted in a maximum reduction of 1 log CFU of caecal Campylobacter colonisation. Therefore it was investi- gated whether these vaccines could be used to protect broil- ers against Campylobacter infection following in ovo vaccina- tion. Embryos were immunised in ovo at day 18 with a bacterin or a subunit vaccine and at day 19 post hatch. These birds were inoculated with C. jejuni according to a seeder model. Quantification of C. jejuni in the broilers’ caecal con- tent showed that the in ovo vaccinated birds were not pro- tected against C. jejuni infection. Quantification of blood an- ti-Campylobacter antibody titers did not show any induction of Campylobacter-specific serological responses in the vacci- nated birds, which may explain why there was no protection in the vaccinated chicks.
In ovo vaccina- tion works well for a number of diseases. Unfor- tunately protec- tion against Campylobacter could not be established.
34
▶ POULTRY WORLD | No. 2, 2020
PHOTO: RUUD PLOEG
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36
