A collection of strategies for helping control all factors impacting the efficiency of in -ovo vaccination in hatcheries. Sponsored by Ceva Santé Animale.

The percentage of hatch is a general indicator and does not provide the full picture of the performance when assessing the impact of a candling system or of an in ovo vaccination process.

To monitor the respect of the vaccine preparation protocols supplied by the vaccine manufacturer are essential to minimize any eventual loss of vaccine quality and vaccine titers

In the context of in ovo vaccination, a comprehensive and regular Hygiene Monitoring Program is recommended. Hygiene regular monitoring through microbiological screening of the hatchery assessed for absolute microbial loading is the best tool for the following objectives.

Embryo development assessments are a key control factor in the vaccination efficacy monitoring.

For many years, layer producers have been vaccinating their pullets against Gumboro Disease through drinking water and, most recently, rHVT IBD. Due to inadequate vaccine take or inability to replicate in the BF, these types of vaccines cannot prevent the replication of field virus in this primary lymphoid organ, consequently preventing the shedding of the field virus to the environment.

The best option to control IBD is to use a live attenuated IBD vaccine, which is capable of reaching the bursa and generate a high level of protection against various types of IBD viruses and effectively preventing shedding. This way, the virus pressure decreases cycle after cycle, and the likelihood of the emergence of virulent variant IBDV can be strongly reduced.

The Gumboro control in pullets includes both protection and prevention. Therefore the objective of Gumboro disease vaccination must be to ensure continuous protection against infection with IBD virus, prevent the build-up of higher virus pressure cycle after cycle, and reduce the risk of IBD virus mutation towards a more virulent strain.

Infectious bursal disease (IBD) or "Gumboro Disease" is caused by the IBD virus that replicates and damages the bursa of Fabricius of young pullets leading to high mortality, susceptibility to other diseases and poor performance.