The study involved ruffling the feathers of chicks with puffs of air. The chicks showed signs of distress at having their feathers ruffled and the mother hens mirrored their stress. The researchers were able to document equivalent signs of physiological distress in the mothers when they observed that their chicks were bothered.
Scientists documented increased heart rate and alertness as well as lowered eye temperature, all signs of distress in chickens.
Scientists working at the University of Bristol as well as groups like Compassion in World Farming have already taken note of the impact that this knowledge could have on the considerations of farm and laboratory animal welfare. Among the most horrifying parts of being an animal on a farm or in a laboratory is having to witness other animals being tortured and killed. Up until now it was thought that most animals weren't capable of empathizing with others in distress.
This study shows that the animals that we most often slaughter for food are capable of not only feeling pain and fear for themselves, but are also capable of being terrified at what they are seeing happening to others around them. In the United States we kill almost 9 billion chickens for food annually, which doesn't even count male chicks killed at birth and egg-laying hens confined in cages their whole lives. Compare that number to only around 100 million cattle slaughtered for beef.
Once again many are missing the point in saying that this study creates an imperative for so-called "better welfare" on farms and in slaughterhouses when what it creates is an even greater imperative to stop slaughtering animals for food entirely.
We don't need friendlier and "happier" slaughterhouses, we need no slaughterhouses. We don't need compassion in animal agriculture, we need to end animal agriculture.
Every step of the way we learn more about animals and how much they are like us and we struggle to continue justifying the fact that we treat animals like property instead of sentient beings.
We've proven that chickens feel empathy with the suffering of others, the only thing left is for us to prove that we as humans feel empathy for the suffering of chickens and other animals.