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Cevac Mass L

Cevac Mass L

It is a freeze-dried, live attenuated vaccine (strain B48) belonging to the Massachusetts serotype of Infectious Bronchitis Virus (IBV)

CEVAC MASS L, a unique IBV Massachusetts Strain


  • CEVAC MASS L is a Massachusetts IBV, strain B48

This strain differs from H120 and Ma5 vaccine strains.

The S1 region of the genome was amplified by RT-PCR and was fully sequenced. The GenBank H120 and Ma5 are nearly identical (>99.5% from this group) and the B48 strain is clearly different, with only about 98% identity compared to the other Mass-type vaccine strains.


  • Comparison between H120 and B48 strains1

3 groups of 48 SPF chickens were vaccinated at Day one by eye drop route and challenged at 23 days of age with 103 EID50 per bird of M41 IBV strain.




CEVAC MASS L offered the best protection evaluated by ciliostasis score and virus recovery after challenge compared to the H120 vaccine strain.


Strong protection from 3 to 6 weeks of age

Challenge laboratory trials in commercial broilers have been conducted at 3 weeks and 6 weeks of age after spray vaccination with CEVAC MASS L at one day of age. The challenge virus was the M41 Massachusetts virus, applied by eye drop at 3.5 log10 EID50/bird.



Ciliostastis score post-challenge after M41 virus challenge (DV-237-2013)

Day one application to commercial broilers demonstrated onset of immunity after M41 challenge at 3 weeks. The latest challenge was at 6 weeks of age with evident protection.


Strong reduction of challenge virus excretion

After challenge at 3 & 6 weeks of age infectious bronchitis challenge virus load in the trachea was evaluated by qPCR.



Day one application to commercial broilers of CEVAC MASS L dramatically reduced the challenge virus load in the trachea after an IBV M41 challenge.


Vaccination program

Multiple Infectious Bronchitis viruses are present globall and often with several viruses circulating concurrently in one country at the same time. Your vaccination program should be able to induce wide-ranging protection in your chicks.

In order to evaluate protection induced by the combination of CEVAC MASS L and CEVAC IBird several studies have been conducted with recent IBV isolates from different parts of the world.



CEVAC MASS L and CEVAC IBird combined in the same vaccination program were able to induce strong protection against these recent field IBV isolates.



References:

1. PICAULT Jean-Paul, LAMANDE Josiane, ALLEE Chantal, MORIN Yannick and COMTE Sylvain; Efficacy study with 3 attenuated infectious bronchitis vaccine strains of the Massachusetts type in SPF chickens. XIII Congress of the World Veterinary Poultry Association, July 19-23, 2003, Denver, Colorado.

2. T Tatar-Kis, Walkone Kovacs E., Felfoldi A., Nagy Z, Kiss I, Mato T, Palya V. Protection 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.

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