PoultryUSA - June 2018 - 15
Read more: Poultry sector spending more on hatchery vaccinations,
Jordan said the spray nozzle is critical for waterbased sprays. Droplet sizes vary due to the type of
nozzle and the level of pressure the fluid is under. Due
to the laws of fluid dynamics, the size and type of the
nozzle as well as the pressure of the system need to be
adjusted on a case-by-case basis to optimize the application needed for each hatchery and vaccine. Gels,
on the other hand, give even, defined droplets with a
consistent amount of the oocysts in the droplets.
How much vaccine is actually ingested?
Jordan studied how much of the vaccine is actually getting to the chicks in the products. He saw that
with sprays, about half of the oocysts are lost between what's mixed up in the vaccine bottle and what
actually gets down to the level of the chick. Small
droplets are also influenced by airflow and may not
reach the chicks. Gels provide larger, heavier droplets
and provide almost no vaccine loss from the bottle to
The larger, heavier droplets carry a drawback, however. While recording a slow-motion video, Jordan's
team noticed that the chicks shake after application of
either a water-based spray or gel product. The waterbased products mat down in the feathers and don't come
off during the shaking. Gels do, which means at least a
portion of the droplets go down to the floor of the basket
where they are unlikely to be ingested by the chicks.
rectly. With sprays, the ceiling is a bit lower than gels
even if application is done perfectly.
However, if there is poor application - or a mistake
- then the floor, or the worst possible vaccination outcome, is significantly higher for sprays than gels.
"With spray, your consistency is going to be there a
little bit more routinely," Jordan said.
Nevertheless, the most important factor for proper
application in the hatchery is the hatchery personnel
itself. If the personnel are not mixing the vaccines and
diluents properly, then there will never be consistent
application with evenly distributed dosage.
"Some hatcheries have really great employees and
have really great hatchery managers who really get buy
in from their staff and they do a great job. And then
some hatcheries, as hard as they try, there's a lot of personnel turnover and they have human error that occurs.
"Some hatcheries have fine-tuned operating procedures for vaccine handling and great personnel who do
a great job," he said.
"The quality control, as far as the application system, is only as good as the people that are operating
it," Jordan said. ■
Which is better?
Jordan said there's no definitive answer as to one
product being significantly better than another. Some
vaccines will work better with gel and others will
work better with spray. Both methods can be used effectively and both carry their own pros and cons. In
his experience, when both products are applied under
ideal conditions, no real difference is seen.
Specifically for coccidia, gel vaccination provides a
slightly higher ceiling of vaccine coverage if used corJune 2018 ❙ www.WATTAgNet.com
Once applied, chicks in the basket preen one another in order
to consume the vaccine product. | Austin Alonzo