Vaccination plays a vital role in ensuring the health and productivity of poultry flocks by protecting them from different diseases and pathogens. Once there is a disease outbreak in a flock house, it is usually very hard to control and it can result in birds becoming lethargic, a reduction in growth rate, and in severe cases even lead to high rates of mortality. Luckily, many diseases can be easily prevented through effective vaccination. Vaccinating the flock stimulates the bird's immune system to produce antibodies against specific invading organisms. However, vaccination can only be effective if properly handled and administered.
Major epidemic diseases including Newcastle Disease and Avian Influenza are known to cause major production and financial losses to poultry operations worldwide. In this way, vaccination is a preferred solution by many farms for eradicating different poultry diseases and ensuring optimal health, growth, and productivity of their flocks.

The poultry's immune system
The poultry's body can protect itself against different pathogens through physical barriers such as the skin, mucus, and cilia. However, these barriers aren’t 100% penetration-proof. This is where the immune system plays a vital role by triggering a response to attack and destroy the invading pathogen.
A pathogen can be a bacterium, fungus, virus, or parasite that causes disease in the body. There are different subparts of a pathogen, but the one which causes the disease is called an antigen. In response to that antigen, the immune system can produce specific antibodies.
Types of poultry vaccines
There are different types of vaccines (live, killed/inactivated) and methods for vaccine administration (in drinking water, eye drops, spray, subcutaneous, intramuscular injections, and in-ovo administration). The type of vaccine and administration method depends on many parameters, including the species, size, health status, innate immunity, length of the production cycle, selected protocol, cost, etc. However, the common ground for all vaccines is that their efficiency is highly dependent on proper storage, handling, and administration procedures. Unfortunately, misapplications during vaccine administration are very common, usually caused due to human error, and are considered a leading cause of vaccine failure.

How poultry vaccination works
Through the process of vaccination, healthy birds are intentionally infected with killed or weakened pathogens in a controlled manner. After receiving the vaccine, the bird's immune system is triggered to respond and activate a group of cells to attack and destroy the invading pathogen. Other cells in the immune system, called memory cells, are in charge of remembering the infectious agent in order to quickly trigger a response if it's detected inside the body in the future. In this way, birds are protected from different diseases and maintain immunity, health, and productivity.
The poultry vaccination process
The process of vaccination can be stressful, painful, and energy-consuming for the birds. Before starting to vaccinate, it is important to ensure that the birds are healthy, as this can negatively affect the vaccination outcome and negatively inflict on the bird's growth rate and productivity. Furthermore, it is essential to strictly follow the vaccination procedure's guidelines and highly recommended to consult with a licensed veterinarian in order to avoid complications related to incorrect vaccine administration.
Injectable vaccines for poultry
The use of injectable vaccines to prevent specific diseases is known to be highly effective against poultry diseases. Intramuscular or subcutaneous injection of vaccine is a common practice of administration, especially for some live and adjuvanted vaccines, and is performed mostly in the breast and lower neck.
The needle size (measured in gauge) should be selected depending on the vaccine type and the injection site, and it should be replaced frequently to reduce the chances of cross-bird contamination. Furthermore, injecting from blunt needles can lead to extensive lesions at the injection site, swelling, granuloma formation, and lameness.
The vaccine should be stored according to the manufacturer's instructions and the expiry date should be checked prior to administration. Some vaccines need to be pre-heated in a warm water bath or by removing from the refrigerator prior to administration. This can also contribute to the reduction of lesions at the injection site.
Injecting poultry with a manual syringe
Despite the many advantages of injectable vaccines, there are also some major drawbacks related to their administration using a manual syringe. These include the stressful and strenuous handling of the birds, forgetting to replace the needle on time, accidentally injecting air instead of the vaccine due to an empty bottle, delivering an inaccurate dose due to poor calibration, and not squeezing the piston all the way through, operator safety is compromised with a high risk of self-injection accidents and repetitive motion injuries and more. The chances for human error when injecting with a manual syringe are high since there is no prompting and feedback to ensure accuracy.

How to ensure accurate injections, from the first bird to the last
Ensuring accurate vaccine administration to every bird is crucial for achieving optimal flock immunity and preventing disease outbreaks in flock houses.
Using an automatic vaccination system can help vaccination crews overcome the obstacles mentioned above. For example, the pHi-Tech vaccination system for poultry provides real-time alerts for injection errors such as missed or incomplete injections, reminders to replace a vaccine bottle once it's empty, prompts to replace the needle frequently to avoid extensive lesions and cross-contamination, notifies in case the vaccine is not at the correct temperature and more. This enables vaccination crews to take immediate action when an injection misapplication occurs and ensure an optimal outcome of the vaccination process, as will be measured by the Titers and CV performed post-vaccination.
The pHi-Tech system has an ergonomic and lightweight design to facilitate effortless administration and reduce operator fatigue and strenuous work injuries that can negatively affect their performance. Its flexible configuration allows for the application of up to two vaccines simultaneously, which significantly shortens the vaccination process and reduces stress for the birds.
Furthermore, the pHi-Tech system collects data during the vaccination event, enabling decision-makers to have full transparency of the vaccination process and implement data-driven decisions for improving their flock's health and productivity.