Infectious Bronchitis in Chickens

Wrinkled Egg - IB Symptom

Back when I wrote about introducing new chickens into a flock (see Introducing New Chickens), I missed one important step, and we’re learning a painful lesson as a result.  It wasn’t enough to ask if the new chickens were vaccinated, we should have kept them separate from our flock for 30 days to make sure they couldn’t introduce disease.  

Infectious Bronchitis (IB)  

As it turns out, Bab and Will brought Infectious Bronchitis into our flock, and it’s destroyed the Golden Buffs ability to produce eggs (it does not affect humans).  Infectious bronchitis is a virus, it’s the most contagious poultry disease, and it spreads rapidly.  It’s transmitted by contact with infected birds, contact with contaminated equipment, and can travel over 1000 yards through the air.  The disease will infect a flock within 48 hours, and those birds that survive recover within 2 to 3 weeks.   

Symptoms  

Gasping, coughing, and sneezing are symptoms displayed by birds with IB; however, we only noticed Bab sneezing – the other birds seemed ok.  What we did notice was a big drop in egg production, and those eggs that they laid had soft, ridged, or non-existent shells.  For awhile I was in denial, thinking it was winter, they were molting, etc.   However, when one of the Golden Buffs produced a “wrinkled” egg (see picture – it’s a classic symptom of IB), I finally accepted that Bab and Will brought disease to the flock.  

Long Term Symptoms  

Infectious Bronchitis damages the reproductive organs of mature chickens, so although they may return to production six to eight weeks after contracting the disease, they may never produce well again.  In the case of the Golden Buffs, they were about two years old and producing well.  Now, they’re seldom able to produce an egg with a shell, and we had the difficulty with the prolapsed vent with Gold Dust (see Chicken Emergency).  Bab was younger and just coming into production, so she’s still able to produce eggs with good shells – but not often (every 2^nd or 3^rd day).        

Treatment  

Survivors of infectious bronchitis are IB carriers, so the only way to eliminate it is to get rid of the flock, clean the pen or coop, disinfect everything, and start over.  IB is supposed to survive less than a week once off the birds, so the probability of eliminating it seems good.   The positive things I can say are that we learned a lot from our birds, they enjoyed an organic/free range existence, and we enjoyed them so much we do want to start over.  We’re drawn to the heritage Buckeye as the type of chicken to start over with.        

Lesson Learned  

The fact that we started with vaccinated Golden Buff pullets (and I think starting with quality stock is important), but it didn’t protect them from contracting IB makes me determined to maintain a closed flock next time.   I’d love to hear from anyone with experience on protecting chickens from IB too – before vaccines but when lots of folks had backyard flocks, what was done?