Infectious Bronchitis

Infectious bronchitis is caused by a chicken coronavirus. This virus is highly contagious and is present all over the world. It has the ability to replicate in the respiratoy tract, the kidney and the oviduct of the birds. It cuases severe economic losses in either broilers or laying hens. Infectious bronchitis is characterized by its capacity to mutate. Therefore multiple antigenic variants are generated and circulate with different, pathotype and immunotype characteristics.^1,2,3

Infectious bronchitis vaccines

Numerous live or inactivated monovalent or polyvalent vaccines are available globally. Vaccination programs are commonly based on the use of live attenuated Massachusetts's vaccines via spray or drinking water.

According to the specific epidemiological situation it is common to combine this strain with a variant strain administered simultaneously at the hatchery or as a booster in the field.

As new variants appear in the field frequently, vaccination schedules have to be adjusted accordingly to the protection they give to the birds exposed ans challenged by new viruses.

Cevac IBird, The vaccine

Cevac IBird is a live attenuated vaccine (strain 1/96) belonging to 793 B group.

Cevac IBird is a freeze-dried vaccince, available in glass vials of 1000, 2500 and 5000 dose presentations.

• Safety

In a field trial, commercial broilers have been vaccinated by coarse spray at the hatchery either with Cevac IBird + H120 and an apathogenic ND vaccine or with a commercial live IBV variant + H120 + Nd apathogenic vaccine program.

Cevac IBird has proved to be safe when sprayed at one day of age on commercial broilers.

• Onset and duration of immunity

Challenge laboratory trials in commercial broilers have been conducted at 3 weeks and 6 weeks of age after spray vaccination with Cevac IBird at day of age.

Day one application to commercial broilers demonstrated onset of immunity for 793 B challenge at 3 weeks. The latest challenge age run was at 6 weeks of age with evident protection.

• Efficacy

Cevac IBird has been tested in several challenge studies to evaluate its efficacy either standing alone or combined with a Massachusetts vaccine in providing protection against several serotypes.

Cevac IBird induces strong protection against 793 B virus strain. 

Cevac IBird in combination with a Massachusetts vaccine strain is able to offer a wider protection for QX, Q1 or J2 infectious bronchitis virus strains isolated from different parts of the world.

• Compatibility

Cevac IBird has been tested in field conditions after the application of Cevac Transmune by in ovo route⁵.

Cevac Transmune administered via in ovo route and Cevac IBird + a live Massachusetts spray at day 1 have been tested and proved to have good vaccine take for Gumboro and excellent protection for IB 793 B & Mass strain challenges. 

Vaccination schedule & application

Cevac IBird can be administered by coarse spray at the hatchery. Desvac specific equipment have been set to apply Cevac IBird at the hatchery.

Cevac IBird can also be administered in the field by spray, with Desvac kit 1 or Desvac Spray Fan for exemple.

Cevac IBid can also be administered by drinking water from 10 days of age.

References:

¹. Cavanagh D and Naqui S,A. Infectious Bronchitis. IN saif YM editor. Disease of poultry 11th edition IA:Iowa State Press; 2003. P. 63-87.

². Cook, J.K;A., Jackwood M. And Jones R.C.. The long view: 40 years of infectious bronchitis research. Avian Pathology june 2012, 41 (3), 239-250.

³. De Witt J.J., CookJ. K. A. and Van der Heijden Harold M.J.F Infectious bronchitis virus variants:a review of the history, current situation and control measures. Avian Pathology june 2011, 40 (3), 223-235.

⁴. T Tatar-Kis, Walkone Kovacs E., Felfoldi A., Nagy Z, Kiss I, Mato T, Palya V. Portection achieved by a vaccination programme comprising Mass and 793 B type vaccines against recent variant IBV strains circulating in the Middle East. VII Symposium on avian corona-& pneumovirus. Rauischholzhausen, Germany, june 2012, 194-203.

⁵. TJ Herczeg, M Papp, L Makranszki, K Varga, Z Penzes. Evaluation the compatibility efficacy of variant infectious bronchitis live vaccine with conventional bronchitis and immune complex IBD vaccine in broilers. XXIV World's poultry congress Bahia 2012.