Broiler chickens that are raised for meat are genetically selected to be fast growing, but they may suffer from heart diseases, according to researchers with the University of Saskatchewan (USask), who noted that heart pump failure is a major health and welfare issue for the broiler chicken industry worldwide.

Globally, economic losses associated with heart failure problems in broiler chickens amount to more than $1 billion annually.

To understand why fast-growing broiler chickens suffer from heart problems, USask researcher Andrew Olkowski and collaborators compared them with slower-growing counterparts, which have a much lower risk of heart failure, and with Leghorn chickens, which are resistant to heart failure.

“I couldn't see obvious changes that could explain heart pump failure under the microscope, so I thought, maybe it's some more subtle problem with the heart muscle proteins themselves that is not apparent on light microscopy. When we looked at that using infrared micro-spectroscopy, it was fairly immediately obvious,” Olkowski said.

Using the Mid-IR beamline at the Canadian Light Source at USask, it was possible to identify misfolded and damaged proteins building up in the heart, the university said.

“The synchrotron allows you to see the conformational changes in the proteins, and we hypothesized that the changes we observed must have a physiological impact on heart pump function,” Olkowski explained.

Further analyses revealed that the chickens had a hard time disposing of these misfolded protein aggregates, with knock-on health effects eventually leading to health failure, he added.

The team’s results, which were published recently in Avian Pathology, suggest that heart issues in fast-growing broiler chickens might be linked to how their genes respond to epigenetic factors, like nutrition and their environment.