In our research four live attenuated vaccines against avian infectious bursitis (two inland produced and two imported) were tested: Biavac, Biaromvac-Pa, Gumboro Vaccine Nobilis 228e and Live Virus Vaccine Tablets Gumboro, M.B. Strain. The research was made in production conditions on 44,400 broiler chickens maintained in industrial system and raised on bedding and in batteries. The broilers were kept in four poultry houses, each of them representing an experimental group. We mention that vaccines were administered only one time. Vaccines efficiency was assessed by immunoenzymatic test. In that purpose, for each poultry house, 20 broilers were isolated and identified by a tibial ring, their immune response being followed between 5 and 42 days of age. Analyzing the results about individual antibodies titer during the experiment, the significant differences were observed both in poultries and phases. The best results were obtained using Live Virus Vaccine Tablets Gumboro, M.B. strain.