Replication-independent reduction in the number and diversity of recombinant progeny viruses in chickens vaccinated with an attenuated infectious laryngotracheitis vaccine.

•Virus diversity after co-inoculation was lower in vaccinated birds than in mock vaccinated birds.•Fewer recombinants were detected in vaccinated birds than in mock-vaccinated birds.•The decreased diversity after co-inoculation was not accompanied by a decrease in virus replication.•Vaccination may select for virus genotypes that replicate and persist in vaccinated chickens.•Vaccination may limit recombination, but only in vaccinated birds, not in naïve in-contact chickens.