Effect of Mycoplasma Synoviae on Broiler Performance

Abstract

Two trials were conducted to determine the effect of Mycoplasma synoviae (Ms.) on broiler performance. A total of 1,200 males and 1,200 females was used in each trial.At 28 days of age, 75 birds per pen were placed, sexes separate, in 32 pens in a house equally divided by a solid partition. The temperature in the house was maintained at 21° C., and the ventilation rate varied from 28 to 56 liters per minute per bird.A combination vaccine for Newcastle disease and infectious bronchitis was given in the water at 28 days of age. All birds were weighed and feed records started 3 days after vaccination. At 32 days of age, all birds in the 16 pens in one section of the house were exposed to an aerosol of a Ms. broth culture. All birds were weighed and feed records terminated at 59 days of age. The four groups, Ms.-free males, Ms.-exposed males, Ms.-free females and Ms.-exposed females, were processed at a federally inspected processing plant at 60 days of age and post-mortem condemnation records obtained.The Ms.-exposed groups had significantly higher condemnations that were due to airsacculitis than the Ms.-free groups. There was a trend for decreased body weight and increased feed conversion ratio for the Ms.-exposed birds.