Secondary Infection after Infectious Bronchitis, Became more of an issue than the IB itself

Infectious bronchitis is a viral disease, there is a blurring in the nomenclature of the IB strains in the world (according to the different countries) in poultry that are vaccinated in the right serotypes and their immune system is healthy. There is no need to use antibiotics. Today's approach is to avoid antibiotics resistance. Current trends are to reduce the use of antibiotics and even poultry grown without antibiotics ever. A method that is globally expanding successfully.

Other than immunization anyway (updated homologous variants or existing strains both classic & variants for IB), exposure of the bird to ammonia also creates damage to respiratory system. It causes ciliostasis at lower concentration for shorter duration & deciliation when exposed to Ammonia in more concentrations (above 25PPM) for longer duration. In winter there is lesser air circulation of air in shed. If it is not properly managed, then dead areas of ventilation are created in some parts of shed, which helps for Ammonia to concentrate in that part of shed. In that area, air quality is compromised, which opens way for Viral primarily & 2ndry bacterial infection establishment resulting into outbreak of disease/diseases.
In summer as there is more ventilation to manage high temperatures within shed so there is no problem of Ammonia but in winter if ventilation is not proper ( both distribution within shed & flow of air through shed) it helps in disease establishment.
It is important for control of respiratory diseases in chicken to give properly designed/organised ventilation.
It is further confirmed by disappearing of such disease problems in summer. Because by increase in rate of ventilation in summer, respiratory problems particularly IB outbreaks significantly decrease.

Respiratory diseases particularly in broiler flocks are very frequent on Pakistan. Be it IB, LPAI H9, E coli, MG interaction with live vaccines or excess ammonia levels (lesser chances during summer seasons due to higher ventilation rates). Little effort is made to accurate lab diagnosis and treatment is attempted by use of Abs. Epidemiological data is scarce. In such situations, farmers are left at the mercy of vets/consultants writing antibiotics and the medicine companies promoting Abs. The situation cannot be improved until extensive field and lab data are available to probe and reach meaningful conclusions.

Dear Dr. Perelman,
Very enlightening information, thanks.

Hi, everyone... Can we go wd IB killed vaccination in broilers? What should be the schedule, please?

Yes, secondary infection after Infectious Bronchitis would be more of an issue than the IB itself, since it is obvious that nearly all diseases of poultry manifest respiratory symptoms. So there is confusion and doubt already on the ground towards a correct diagnosis. In this manner, the only sure guide is a definitive diagnosis. This might be difficult under field condition in Nigeria, hence the condition and diagnosis is delayed and thus progresses from bad to worse allowing secondary bacteria infection to complicate the condition. In a worse situation, broad-spectrum antibiotic and multivitamin could be resorted to.

Dear Anwar,
It appears there are challenges with poultry farm biosecurity and antibiotic resistance in Pakistan.
Some of the signs you mentioned i.e. urogenital and kidney involvement as well as anorexia are part of what is observed in Infectious Bronchitis. I suggest a proper identification of circulating strains of IB virus in your country in order to pursue homologous vaccination. Also, only cases with secondary bacterial infection be treated and not a routine approach.

Detoriation of egg quality (weak & misshapen eggshell with watery albumen) is often seen by me in com. laying & breeding flocks of Pakistan and Middle East.

Usually farmers, particularly in Pakistan, are not using IB Variant vaccines during the rearing period.

Is it advisable & beneficial to use IB Variant vaccines, like 4/91 during laying period in the presence of IB problem?

Based on my experience, I agree that use of both classical IB-H120 & Variant IB 4/91, generally resulting in better control of IB problem in layers & breeders.

Is it possible for MSD to introduce safe combined IB vaccine, containing IB-H120+IB 4/91 in a single vial? I am sure this could make the life of farmers easy.

Regards,

Dr. M. Akram, Micro Lab, Karachi.

Dear SIr,

Biosecurity, correct management and strategic vaccination are required to eliminate the occurrence of Infectious Bronchitis in broiler farms - easier said than done? YES, it will be a long shot!

First, we must fix the biosecurity issues in the area. We are still hopeful to encourage the farmers to promote basic biosecurity protocols in the farm with the help of private and government veterinarians. The moment we give up on biosecurity, the farms will be vulnerable to many infectious diseases and the economic impact would be really great.

Second, strategic vaccination would be necessary. Know the immune status of day old chicks against IB for example thru ELISA and to determine the age to vaccinate in broiler farms. We can check the strain of IB circulating in the area thru PCR. Once we identify the culprit strain of IBV, then we can design a vaccination program. In our country, the trend in broiler vaccination is going into "no or less vaccination at farm level" due to many errors related to vaccination procedure, majority of vaccines are being given in the hatchery by trained personnel.
For farms having problem with IB, we might want to check also the vaccination procedure in the farm and we can also check the effectiveness of vaccination thru serology (CV% and titer levels).

Third is management, Dr.Jaffery was right about the contributory factors to the occurrence and severity of infections in the farm. Regardless of how frequent vaccinations against IBV are, if management issues (such as crowding, high ammonia level, extreme temperatures, biosecurity issues etc.,) are present, it is impossible to control the infection at farm level.
One unique feature of viral infection is immunosuppression. Antimicrobial therapy is necessary to minimize the losses to IB. Correct choice of antimicrobials (based on sensitivity testing) with accurate dosage is required to treat the secondary bacterial infections. Ensure also the correct distribution and volume amount of antimicrobial solution per house based on flock population.

Hope this suggestion may help you, sir.

Dear Colleagues My suggestion is to use IB variants if isolate is filed virus, please do not confuse with field and vaccinal virus. Excessive use of variant vaccines without knowing vaccination period results in collapse of immunity.

Coinfection with LPAI as well as Mycoplasma has proven to increase losses significantly.

IB vaccine H120 is widely used on day one. This is done at hatchery by spray. At brooder house by beak dipping before releasing on day one. Possible for small flocks where Labour is available.
H 120 + nd lasota is given on day 5 by eye drop or sinking water.
The variants given during growing and laying are MA5 or 4/91. 4/91 is opted when results with MA5 are not up to the mark.
Most of the killed vaccines are combined with ND, ND, IBD &TWO. The strain used in killed vaccines are generally M41 or M49.
Live vaccine for layers in drinking water can be given safely to boost the titers. MA5 is the strain of choice. If found not working go for 4/91. The problem in vaccinated layers is seen as misshapen and white colour eggs in brown layers.
Live MA5 in drinking water does help in boosting the titets and improving the egg quality.

Seroconversion of IB killed vaccine are very low in broiler breed, as well killed vaccine available for common strain not variant type so using such as techniques of strategy a kind of hopeless efforts and wasting time, I prefer to boost the breeder flocks with killed vaccine at 40 weeks neither vaccination of broiler flocks.

I 100% agree with Dr.Ahmed Anjum that during the wheat threshing period, this stat of non pathogenic problem erupted due to not only due to dust particles but along the dust very tiny particle of wheat plant stem are very harmful as the particle penetrate into respiratory system right from the trachea, bronchi even in to the lungs & there is no way to take these particles out. There is little hope that Bronchi dilator can help a little bit but these will damage the lungs, path gins specially IBV can attack in these favorable conditions. I would like to suggest that during these months, direct air suction should be avoided. Air suction can be done through cooling pad with single tunnel fan subject to the cooling pad should be wet all the time, if it down the temperature, wet garden green cloth can be used over the pads to stop the dust to avoid inside the house.
Other tan these month IB-H 120 & 4/91 after each vaccine on third day Antibiotic which is according to sensitivity test can be given for 3 to 5 days I am sure it will pay an important roll to protect secondary infection. I am suggesting in my long personal experience.

Wish to be successes full.
Kind regards to all viewers.

Hello Francisco.
Could you write the time vaccination for this Ma5, 4/91 you prefer?

Thank you very much for this informative and well educative article. Haven't gone through this, I have learned so much from you, while considering the biosecurity.

Dear Sir, 

Can we use vit c during IB outbreak? It will be helpful and which type of immunity. Will be enchanted.

I am responsible for supervising the health of broiler breeder chickens at several farm sites. One of the farms is currently in production. from 30 hen houses, there is a hen house at the age of 27 weeks of egg production is difficult to ride is 11 days still the egg production below 70%. there are 29 hen houses have good production, there is even one hen house can reach % EP = 90.
At the time grower IB vaccine program that I use start from the first age is as follows:
Age 1 day with IB Ma5 vaccine spray in hatchery.
Age 21 days with mass ib live vaccine and ib killed vaccine.
Age 7 weeks with ib ma5 vaccine and ib killed vaccine.
Age 12 weeks with mass ib live vaccine and ib killed
Age 18 weeks with ib mass live
Age 24 weeks with vaccine ib killed.
I do surgical carcasses both against dead chickens or culled chickens. The obvious pathological change is the presence of clear fluid in the oviduct of about 400-500 ml, the wall of the oviduct becomes thin and width of the size can reach 5-7 times the normal size. The order of egg follicles is normal and the number is 7-8 folikel from the largest to small. Temporary suspicion on the cage is infected with IB QX virus.
The question is:
1. Whether the vaccine is not protective against IB QX virus field.
2. Why the oviduct is infected while the egg follicle remains normal. Approximately start when virus infects the chicken.
3. What action should be taken to avoid transmission to another chicken coop.
Please advice and opinion.