Fowl Cholera in poultry

Dear Muhammad Faeooq Qureshi, Thank you for sharing your experience! Regarding the subcutaneous injection on the rear part of the head or in the upper part of the neck, care have to be taken because I have seen very serious skin necrosis, particularly when the vaccine is administered to young animals, for example to 5 week-old chickens. Best regards, Dr. Horacio Raúl Terzolo

Dear Dr. Cherukuri Choudary, Thank you for all your useful comments! Regarding the rodents I have to say that P. multocida is very pathogenic for rodents. A subcutaneous or intramuscular injection of primo-isolates of P. multocida from chicken outbreaks kills a mouse in less than 18 hours. I think that probably mice living in contact with chronically infected chickens may become resistant to dead and be a carrier of the disease. Best regards, Dr. Horacio Raúl Terzolo

Thanks for the discussion please. What is your take on vaccination in general and the cold chain? And; do local chicken too, require vaccination without break?

Dear Lwetutte Julius, The cold chain is not so crucial for inactivated vaccines, the most used vaccines against fowl cholera. More care has to be taken for live lyophilised vaccine strains. The best is to transport and keep both type of vaccines around 4-7°C. In case of not having outbreaks of the disease it is always advisable to prevent administering bacterins. In these cases live vaccines are not recommended because may retain some virulence. Remember that Pasteurella multocida does not only causes fowl cholera but also complicates and aggravates other diseases, such as infectious coryza among others. A bacterin containing of serotypes 1, 3 and 4 of P. multocida should be injected by intramuscular or subcutaneous route around 20 weeks of age, administering two doses of bacterin separated by a 3 to 4 week interval. In this way hens will be immunised before posture. Best regards, Dr. Horacio Raúl Terzolo

Thank u dr Yosef huberman

Dear Authors, It is really a knowledgeable article on Fowl Cholera. I got some additional information on this disease. In my lab, I am successfully culturing the P. multocida from liver of suspected birds on chicken blood agar, keeping the plates in candle jar. No growth on MacConkey agar and microscopic examination of growth from chicken blood agar and also examination of bipolar bacteria from liver impression after staining are supporting the identification of P. multocida to some extent. Ref. to your article I shall add some more tests for identification. In order to produce bacterin using alumunium hydroxide gel as adjuvant for common use, is it advisable to use more than one culture to get broader coverage against different sub strains? Your valuable comments on this shall be highly appreciated. Dr. M. Akram, Consultant Microbiologist, Micro Laboratories, Karachi, Pakistan

If the autogenous vaccine is used on the same farm where it is collected from, ot will work and will save time. For prevention many companies are manufacturing multi strain vaccines. It is better one goes for tested multi strain vaccine for the purpose of prevention in a farm where no disease is reported.

Dear Dr. M. Akram, Many thanks for your comments and question. Many bacterins are prepared with 3 strains of serotypes 1, 3 and 4 of P. multocida, which are the most common. If you can isolate a local strain and prepare a bacterin for local use, you may get very good coverage. Nevertheless, these vaccinated chickens will not be completely protected in case of the appearance of a new strain. There is no cross-protection between different serotypes. Yosef Huberman

Agreed. A comprehensive discussion on fowl Cholera almost covered all aspects. Thanks to all valued Members for putting their practical and Technical knowledge sharing. It should be continued for other Poultry diseases as well.

Dear Dr. Mohammad Akram, Thank you for all your comments and your encouraging opinion of our article! Regarding autogenous bacterins, I would like to complete the useful information of Dr. Huberman by adding one more comment. We refer that these autogenous vaccines based on aluminum hydroxide gel adjuvant are highly recommended. After getting or buying a good quality gel you only have to mix the gel to the grown inactivated broth at the correct proportion, which is easier to handle than any oil for any small lab, whereas oil adjuvants need a mixing technique that requires machinery and expertise to develop a well done double emulsion solution between the oily spheres and the water of the gown broth to avoid secondary lesions or even necrosis at the site of injection. If the aluminum hydroxide gel has very good quality the immunity of the vaccinated chickens will last longer that a bad quality gel. In addition to imprints from organs or blood, where you will observe the typical small bipolar bacilli you may perform a Gram stained smears from agar plates. As we showed in the picture of this article, you will predominantly observe very small red coccoid forms with occasional filaments. Additionally, P. multocida is always oxidase positive and ferment glucose but always without formation of gas (for example in Kligler agar stabs, avoid TSI due to sucrose content) and is always non-motile on any stab agar (TTC or SIM among others). All these are very simple basic tests. Finally, we have to insist that vaccine strains should be kept frozen (into a deep freeze or submerged into liquid nitrogen) for conservation, in this way the loss of virulence is avoided. For the bacterin broth seeding an isolate kept onto agar plates must be immediately used after isolation. By keeping isolates onto plates during some days will provoke loss of virulence together with loss of important protected antigens. Therefore you have to freeze isolates immediately meanwhile completing the biotyping with aliquots of the same isolate. I hope that these comments may be useful for you and other colleagues! Best regards, Dr. Horacio Raúl Terzolo

Dear Dr. Talapaneni Kotaiah, As stated previously in the article and the comments of colleagues, if the autogenous vaccine is used in the same farm and according to good bacterin elaboration and conservation of strains (see above my information to Dr. Mohammad Akram), it is expected that good protection results will be obtained. Interestingly, Dr. Morrow brought very important information regarding in vivo LPS expression as responsible for the antigen changes of isolates and he stated that if we could switch to modern live PM vaccines having these antigens we could have a more comprehensive vaccine. Please see above Dr. Morrow’s answers and details of published papers on this matter. Other important comment is that live vaccines generally elicit more cross protection among isolates than inactivated vaccines. Of course, if the farm has no background of fowl cholera, the best will be to order a complete commercial vaccine. For details on these subjects also read the comments and questions made by Nosheen Naheed, Lwetutte Julius and Dr. Mohammad Akram together with the comments and answers of Dr. Huberman and myself. Best regards, Dr. Horacio Raúl Terzolo

Dear Muhammad Faeooq Qureshi, You are quite right it is necessary interchange information about all these subjects. Our expertise is on some poultry bacterial diseases and for that in future we will also prepare an article about Infectious Coryza. Also we will approach these diseases considering the real situation of different countries. Best regards, Dr. Horacio Raúl Terzolo

The diagnostic laborataries do not have facilities to handle larger volumes of material required for flock vaccination. Handling live bactrins can be very risky.

This is a very wonderful and excellent article on Fowl Cholera by the authors, as well as the insightful comments of colleagues. Good job!

Dear Dr. Yosef & Dr. Horacio Raul Terzolo, I am grateful to both of you for your prompt & comprehensive reply. Best Regards Dr. M. Akram

Dear Dr. Talapaneni Kotaiah, Your observation is pertinent. Surely it is very dangerous that a diagnosis laboratory make any type of vaccine, particularly if this laboratory works with isolations of pathogens of all kinds, do autopsies of unknown diseases at the time of sampling and inoculate embryonated eggs in order to diagnosis viral diseases, such as Newcastle and influenza virus, among others. But diagnosis labs should keep and conserve strains that may be candidates for autogenous vaccines. Therefore it is essential that diagnosis laboratories will able to properly send isolates to local manufacturing labs having a good communication between both types of laboratories. Working together and acting fast a good assistance will be provided to the farmer suffering an outbreak. Besides, more sophisticated big vaccine enterprises will produce standard vaccines for general preventive vaccination schedules for farms not suffering an outbreak. For this disease, may be that future development of P. multocida live vaccines based on LPS would produce a biologic product able to cross protect many against many local strains. Anyhow at this stage keeping a collection of local strains isolated from vaccine failures will be very useful for testing this vaccine in cross protection trials. Best regards, Dr. Horacio Raúl Terzolo

Dear Perez Khan, Thank you for your encouraging comments! Best regards, Drs. Yosef Daniel Huberman and Horacio Raúl Terzolo

Dr. Mohammad Akram We are glad to know that the information we gave to you was useful! There is one more subject of interest for you as Consultant Microbiologist. This is the method we use for freezing any bacterial strain, also applicable to P. multocida. We use thermal containers for liquid nitrogen rather than deep freezers to avoid strain damage due to electricity failures. The procedure is as follows: 1) Growth the primo-isolate onto a blood agar plate, for example Columbia blood agar and aerobically incubated the plate overnight at 37°C. 2) After incubation, collect the growth by means of a wire loop of a Kolle handle until making a lump. 3) Deposit the lump (without disaggregation) into a small 1-2 mL vial containing 0.5 mL of tryptose phosphate broth (or other rich broth such as brain-heart infusion) plus 5 per cent (v/v) of decomplemented equine serum and 17 per cent of tyndallized glycerol (more proportion of glycerol may produce mutations of the strain). 4) Put the vial into a canister of a thermal container and directly submerged it into the liquid phase of liquid nitrogen. To recover the frozen strain thaw the vial, capture the lump out of the thawed broth and use the lumped growth to streak (cultivate diluting) a blood agar plate. For transporting strains you may use Ames transport medium or directly a serum agar base slop tube. Best regards, Dr. Horacio Raúl Terzolo

Dear Dr. Horacio Raul Terzolo, Thanks a lot for your additional recommendations to preserve the P. multocida culture. Best regards Dr. Akram

CHER DR .HORACIO je suis interesser par un autovaccin cholera aviaire DR HORACIO vous pouvez me conseiller et renseigner 1_combien il faut de colonie de pasteurella multocida et dans combien d'eau physiologique steril il faut pour un cheptel de 2000dindoneau chair et 2000 poulet de chair 2_a qu'elle doses en l'utilise 3_il faut l'inactiver a la chaleur 60 c pendant 1 heure ou un traitement chimique par le formol a qu'elle dose de formol 4_est ce que c'est suffisant de l'injecter sans adjuvant ou c'est mieux avec un adjuvant est a qu'elle dose se n'est que la curiosite d'un homme de terain qui veut faire de son mieu MERCI DR HORACIO