Evaluation of Tylosin in Preventing Egg Transmission of Mycoplasma gallisepticum in Chickens

Tylosin has been found to be an effective antibiotic against Mycoplasma gallisepticum (1,2,11). Crawley and Fahey (4) suggested repeated injections of an antibiotic into breeding hens to prevent the transmission of M. gacllisepticum through eggs. Osborn and Pomeroy (8) failed to eliminate egg transmission in turkeys by injecting and feeding antibiotic. The technique of dipping fertile eggs in antibiotic solutions prior to incubation in an attempt to control this mode of transmission of M. gallisepticum has been reported by a number of investigators (3,5,6,7,9). The objectives of this study were threefold: 1) To establish a technique for producing a high rate of egg transmission following artificial inoculation of chickens with M. gallisepticum. 2) To determine the effectiveness of tylosin treatment of chickens in preventing egg transmission. 3) To determine the effectiveness with which M. gallisepticum within the egg was inactivated by dipping in tylosin solution.