Continuous evaluation and training are critical to improving pullet vaccination accuracy.
Brand Insights from Zoetis
Vaccines help maintain the health status of poultry flocks, and producers are opting to use more vaccines due to increasing disease pressures, the availability of new vaccines for additional diseases and longer-lived flocks.
More vaccinations mean more bird handling β especially for individually applied vaccines β and proper vaccine administration techniques are of increasing importance.
In commercial layers, typical vaccination programs involve the use of multiple live vaccine applications that are later complemented with killed vaccines before pullets are moved to the lay house.
Vaccines have costs associated with their use, including the price of the vaccine and the cost of labor for administration, especially in layer chickens and other long-lived birds that are vaccinated in the field at older ages.
If vaccines are not stored, handled, mixed or applied correctly, the vaccine may not trigger the desired immune response, and the costs associated with the vaccine are wasted. Proper handling is important for all vaccine types, and manufacturer instructions should be strictly followed.
Vaccinating pullets or older hens β particularly for individually applied vaccines β can be a time-consuming, labor-intensive job completed by vaccination crews either employed directly by an egg company or crews contracted to vaccinate birds for multiple operations.
A key element in a successful vaccination program is making sure vaccination crews are following proper procedures.
Pullet Vaccination Evaluations
A pullet vaccination evaluation (PVE) measures the overall performance of vaccination crews in multiple areas, including:
- Crew safety
- Vaccine storage and preparation
- Bird presentation and welfare
- Equipment information and maintenance
- Placement evaluation
To assess the success of vaccination crews, the results of 25 PVEs conducted from 2021 to 2024 were evaluated to see which factors influenced vaccination success. Comparisons were made between conventional and cage-free systems, between company and contract crews, and among different routes of administration for individually applied vaccines.
Of the 25 PVEs included in this analysis, 44% of birds were vaccinated at 12 weeks of age, 24% at 10 weeks and 12% at 9 weeks. Most of the flocks (52%) were caged, with 28% on floor systems and 20% in aviaries. The majority (68%) of evaluated crews were contract crews.
Wing web results
Equipment used were wing web stabbers and pox vaccinators (Grant applicators). In a single administration, either one or two vaccines were included in most cases (42% for either) with 17% applying three vaccines.
Company crews were found to have the highest placement accuracy (92% vs. 84%), with accuracy around 90% for caged and aviary birds. Crews using wing web stabbers were more accurate (92%) than those using Grant applicators (80%).
Eye drop results
As with wing web vaccination, company crews were most accurate in placing eye drop vaccines at 99% compared with 82% in contract crews. Applicators were more accurate in placing eye drop vaccines in caged hens (94% versus 88% for aviary and 81% for floor systems).
Intramuscular/subcutaneous results
Equipment options included single- or double-barrel automatic injection guns or automatic devices such as the Double Breast Vaccinator (DBV).
As with the other routes of administration, company crews had the highest placement accuracy (99%) compared with 89% for contract crews. Crews working in caged systems also had the highest placement accuracy relative to those working in aviary and floor systems. When applying two vaccines, accuracy was about 87% for single-side injections but 80% for split-side injections. The use of automatic devices such as the DBV resulted in 100% placement accuracy. Crews also were more accurate placing vaccines in the breast (92%) and biceps (90%) than the leg (85%) and inguinal fold (78%).
What does this mean?
There is room for improvement in administering vaccines via all vaccination routes, as well as in different techniques and equipment within a vaccination route, e.g., crews using traditional stabbers for wing web vaccines were more accurate than those using Grant applicators.
What can be done?
Continuous evaluation and training are critical to improving vaccination accuracy, not just for new employees but also for experienced members of the vaccination crew. Periodically, evaluate vaccination practices such as handling and mixing techniques before vaccination and vaccine placement during vaccination. You can also do pre- and post-vaccination serology to have even more information to evaluate the live and killed vaccine application and the crew performance.
Many crews may lack understanding of the importance of proper vaccination practices and some concepts are hard to understand, but most crew members genuinely want to do better and are open to feedback. Additionally, for many crew members, English is not likely to be their first language. Providing training in the crewβs language will help crew members understand the importance of their tasks. Demonstrating techniques or providing visuals of procedures also can help crew members understand how critical their role is for a successful vaccination.
Zoetis can assist with conducting PVEs for layer flocks, including spray and water application methods. Contact your Zoetis representative to schedule a PVE and learn more about how you can improve vaccine administration.
By Fernando Ruiz-Jimenez, DVM, MS, DACPV, technical services veterinarian, Zoetis
All trademarks are the property of Zoetis Services LLC or a related company or a licensor unless otherwise noted.
Β© 2024 Zoetis Services LLC. All rights reserved. NA-03814