Gel-Pac® Improves the Titer of Live Infectious Bronchitis (IB) Vaccine for Poultry Hatcheries

Live IB vaccines were originally developed and delivered by nose drop to poultry because, logically, the respiratory tract was the tissue we were trying to protect by a mucosal response.  However, eventually the economic pressure from high labor costs in developed poultry markets forced researchers to seek more cost-effective ways to deliver live virus vaccine and protect poultry.  During the 1950’s the IB vaccine strains were confirmed as being viscero-active, meaning they are able to provide immunity and protect the respiratory tract from disease challenges even if they are swallowed, not inhaled.  From that point IB vaccines have been mass applied via both hatchery aerosol spray and drinking water.  Dosing by spray at day-of hatch is still favored over dosing by drinking water after placement because, among other things, earlier application provides earlier onset of immunity.

Beyond the time and labor savings, reducing the number of times a hatchery sprays chicks is desirable because each successive pass through a vaccine mist wets the birds and induces thermal shock. Three different vaccines are commonly sprayed in the hatchery; they are vaccines against coccidiosis, Newcastle disease, and IB.  When possible, hatcheries prefer to combine multiple vaccines in a single spray to reduce the number of passes and the amount of water that soaks the birds.  Another way to avoid soaking the chicks is to apply the vaccine in a firm gel spray.  Gel spray droplets rest on top of the feathers instead of soaking to the skin.  Chicks naturally preen the large gel drops and thereby pick up the vaccine in concentrated form, where it can directly generate immunity.