Measuring the "feather viral load" in birds could better inform breeding programmes.

“It’s important to have multiple strategies available” - Prof. Andrea Wilson.

Breeding poultry according to their capacity to shed virus from feathers could help improve protection against Marek’s disease, according to new research.

Scientists at the Roslin Institute found that while genetic resistance protects birds from infection, only vaccination significantly reduced the amount of virus released into the environment.

While this confirms previous findings, researchers note that current vaccine developments and breeding programmes focus on genes linked to survival and tumour resistance in individual birds. This means that traits linked to reduced virus spread within flocks are often overlooked.

Researchers suggest that measuring the “feather viral load” in birds could better inform breeding programmes and support the development of new vaccines.  

Professor Andrea Wilson, chair in infectious disease genetics and mathematical modelling, said: “Vaccines have a limited shelf life, and we know from history that Marek’s disease virus periodically evolves to become more harmful.

“That means we are likely approaching a point in time where increased disease pressure could emerge, so it’s important to have multiple strategies available – breeding to limit viral shedding gives poultry producers another tool in the toolbox”.

Image (C) N_Design/Shutterstock.com