Administer one dose (0.3 ml) by intramuscular route from the age of 18 weeks and at least 4 weeks after the priming with live vaccines against Newcastle Disease (strain Hitchner B1 or VG/GA), Infectious Bronchitis (strain Mass H120), and avian pneumovirus (strain PL21). Shake well before use. Apply usual aseptic procedures. Do not use syringes with natural rubber or butyl elastomer pistons. Equipment including needles and syringes must be sterile before use.