Steps to ensure vaccination success
Although it's been a common practice in poultry production for years, mass oral vaccination remains relatively new to pork producers. Get a jump on best-management practices by running this checklist.
Has diagnosis been confirmed?
Work with your swine health practitioner to ensure a proper diagnosis. Seroprofiling offers a relatively easily performed and interpreted test for exposure to the organism that causes ileitis. Because antibodies don't tend to persist more than three to six weeks when the disease level is mild or moderate, samples should be collected every four to six weeks to monitor for infection.
How many to sample? Accurate diagnosis is achieved when you target a low prevalence of infection — typically 5 percent — at a reasonably high confidence level. Typically, 30 samples per age group will give you an 80 percent confidence level that you will detect early infection at the 5 percent prevalence.
Is vaccination being placed at the correct time in the exposure window?
The seroprofiling your veterinarian does to confirm infection is equally valuable in targeting vaccination timing for best effect. Vaccination should occur at least three to four weeks before you suspect infection will occur.
Cross-section seroprofiling — blood testing different aged pigs at the same point in time — identifies the target window in time. That window takes into account the lag between the time you administer vaccine and the time pigs are first exposed to infection, as well as the lag between the time that exposure and infection occurs and seroconversion follows. Adding both those lag periods together helps your veterinarian place vaccination sufficiently ahead of infection to get the best effect — generally two months before you believe seroconversion will appear.
If you don't have a database of herd-specific diagnostic profiling to accurately identify proper vaccination timing, the time frame should default to the mid-nursery phase (5 to 8 weeks of age) for most operations. Adjustments in timing may need to be made periodically based on potential changes in infection dynamics and observed responses to the vaccination.
Is vaccine being thawed correctly?
Enterisol
Are proportioners working properly?
Before vaccinating, assure that the water system is free of leaks or restrictions. Turn off chlorinators, acidifiers, and peroxide units. Proportioner preventative maintenance kits are available from their respective manufacturers and should be included in your regularly scheduled preventive maintenance.
Has the medicated feed been withdrawn on time?
Because medication can interfere with pigs' response to vaccination, it's important to ensure they receive no medicated feed for at least three to four days before and after vaccination. A week post-vaccination is even better.
New microtracer technology to determine the presence of medications in the feed makes an easy quality control check. Also, it's prudent to keep composite feed samples from several feeders on the day of vaccination if later confirmation of inadvertent antibiotic contamination proves necessary.
Does every pig receive a full dose?
The day before you plan to vaccinate, measure the amount of water passing through the proportioner in a four-hour period during the same time of day you plan to vaccinate. This is the total volume of vaccine-containing stock solution you need to prepare the next day, and the amount that pigs should consume in four to six hours.
Once the stock solution is mixed and being supplied to proportioners, make sure stock solution is being siphoned correctly. Bleed barn lines by opening either a drinker or a spigot, if available, at the end farthest from the proportioner until the blue-dyed water appears there. Check the system periodically during the process to make sure vaccine is still being delivered.