EN
In a flock of 9500 18-week-old Messa chickens the acute form of Gumboro disease was diagnosed. The mortality rate was 6.94%. The disease progressed classically in the flock. The highest mortality occuring on the 3rd and 4th days. Large area hemorrhages were noted in the skeletal muscles and in the proventriculi, as well as an enlargement and necrosis of Bursa of Fabricius. Sixteen days later, a high serum antibody titer of 3-9 log 2 (mean 6 log 2) was observed in all the birds. Egg production increased significantly upon recovery. No immunosuppressive effects from IBD Virus infection were observed.