Ahead of the curve.  A better system is to get a head start, developing immunity from a vaccine by giving it to the pigs before they are weaned and grouped in different facilities, exposed to new challenges.  Underline is the ideal solution.  By simply mixing and spraying the oral vaccine in a gel made from the farm’s own tap water and Underline, managers can immunize the pigs before weaning without the chasing and catching or needles, syringes, and drench guns.

Vaccine Research

Erysipelas vaccine is one of the bacterial antigens that have been adapted to dose orally.  A major roadblock to building strong immunity with oral erysipelas vaccine is that the vaccine is fragile.  Erysipelas vaccine, even when it is diluted in seemingly harmless distilled water, can lose over 60% of its potency in less than 30 minutes, and 85% in fewer than 2 hours (figure 1).

“Underline is capable of stabilizing a delicate live erysipelas vaccine, rescuing it from threats and making the gel even safer for the vaccine than distilled water”

For a fragile erysipelas vaccine to be conveniently combined in a gel spray with tap water or well water, the gel must not only provide positional stability, meaning freedom from settling, it must also insulate the vaccine from threats like oxidation, variable pH, and electrolyte balance.  Vaccine researchers at Gut Bugs, Inc. experimented to learn if Underline could preserve a live commercial erysipelas vaccine, rescuing it from inactivation by chlorinated water throughout the gel spray process.  As an oxidizer that is commonly found in water systems, chlorine represents a more severe threat to vaccine.  If Underline could reliably stabilize and protect sensitive erysipelas vaccine in tap water, it would allow veterinarians to confidently and conveniently spray it in the gel carrier to accelerate the onset of immunity.

Method. A commercial avirulent live Erysipothrix rhusiopathiae vaccine was thawed in a cold water bath for 45-60 minutes and then diluted to 1 label dose per 10 ml to replicate common gel delivery dilutions for preweaned pigs:

Distilled (DI) water, which verified the initial amount of vaccine input4 ppm chlorinated DI water, serving as tap water4 ppm chlorinated DI water plus Underline added at label concentration

Vaccine titers were measured in triplicate upon input and after 30 minutes, 2 hours and 4 hours in suspension by plating samples to quantify the vaccine antigen CFU concentrations.

Vaccine Titers.  The baseline titer of the erysipelas vaccine input at time 0 was 10 x 108 CFU/ml (figure 2).  Interestingly, the vaccine inactivation in non-stabilized chlorinated water was so immediate that even before plating at time 0, the vaccine lost virtually all measurable antigen, suffering more than a 5 log reduction.  Subsequent concentrations in the chlorinated solution confirmed the vaccine CFU were too few to count (TFTC).  In comparison, using Underline to stabilize the same water source in a gel suspension sustained the original vaccine potency throughout the entire 4 hours, with titers at 30 minutes, 2 and 4 hours measuring 9.8 x 108, 6.7 x 108 and 9.4 x 108 CFU/ml, respectively.

Impact

Underline provides a novel delivery system that allows farmers to mass-apply orally-active supplements to baby pigs, in a form they will voluntarily consume as early as the first day of age.  The dry powder mixes with ordinary farm tap water into a viscous, edible gel that piglets voraciously consume from the udder without the stress of catching, handling and individual dosing with syringes, pump bottles or drench guns.  The gel is a delivery vehicle into which a wide variety of nutrients, vaccines, probiotics and functional food additives may be blended.  The viscous gel and the orally-active supplement integrated with it are sprayed directly onto the underline of sows using an ordinary pressure sprayer.  The gel adheres to the sow’s udder, remaining in position and available as the piglets voluntarily consume it.  If desired, the concentration of gel powder may be varied to change the viscosity to carry a variety of active components.

Producers have commonly used Underline to deliver live probiotic bacteria in the adhesive gel.  Consequently, Underline also contains stabilizers to protect and preserve live biologicals from inactivation by oxidizers that may exist in the farm water supply.  Additionally, the gel also manages pH and balances electrolytes to strengthen the stabilizing properties.  This recent research confirms that Underline is capable of stabilizing a delicate live erysipelas vaccine, rescuing it from threats and making the gel even safer for the vaccine than distilled water.  Improving the stability of the vaccine translates into greater immune protection for pigs, and delivering the vaccine before weaning can accelerate the onset of immunity.  Building earlier immunity and safeguarding health before weaning opens up more flexible treatment options for managers and veterinarians when pigs are subsequently weaned and regrouped in different facilities.