The question of how animals feel has been a central focus in welfare studies for a long time, but recent research by a professor at the University of Mississippi may provide valuable insights.
The study involves two young chickens and a mirror.
Kenneth Sufka, a professor specializing in psychology and pharmacology, collaborated with a group of animal welfare researchers from the UK to examine the emotional states of birds by analyzing the sounds made by domestic chicks. Their findings were recently published in Applied Behaviour Science.
The results hold the potential to enhance animal welfare within the poultry industry and also improve the testing for treatments for human conditions like depression and anxiety.
“We aimed to find a noninvasive method to measure stress levels in freely moving animals,” he explained. “This chick study was designed to analyze the vocalizations produced, using a more advanced method than I’ve employed before.”
In their experimental design, the UK researchers built upon previous work done in Dr. Sufka’s lab. The setup included sophisticated acoustic tools within an isolated room. One box contained a chick, while the other housed a chick with a mirror.
The chick that sees its reflection feels less alone, producing vocalizations that suggest a calm demeanor, whereas the solitary chick emits louder, higher-pitched sounds, indicating a possible state of anxiety. The acoustic data collected by the researchers measured changes in the quality of the chicks’ vocal sounds and what those changes revealed about their stress levels.
Identifying stress in chickens could lead to more compassionate and effective practices within the meat and egg industries.
“There is a genuine concern for animal welfare in production facilities, whether it’s cattle, pigs, or birds like chickens,” he noted. “I believe utilizing acoustic monitoring for animal welfare in these industries is a valuable endeavor.”
While it’s well-known among researchers and farmers that loud chicks are distressed, the understanding of this phenomenon is deeper than previously recognized, according to coauthor Sarah Collins, an associate professor of animal behavior at the University of Plymouth.
“This provides further evidence of animal sentience — their capacity to feel emotions,” she noted. “We’ve known for some time that distress calls in chicks signal stress, but this research enhances our ability to precisely assess their welfare.”
This study also introduces a noninvasive and relatively low-cost method for examining anxiety-like states in animals. Traditionally, measuring an animal’s stress required capturing them and taking blood samples to assess corticosterone levels, a stress hormone.
“This method can be inherently stressful — for both the animal during capture, restraint, and release,” Sufka remarked. “We believe that our approach is a significant improvement.”
Medications designed for humans typically undergo testing in chicks, rats, and primates before heading to human trials. Thus, gaining insight into chick emotions could refine anxiety and depression drug studies.
Like many humans, chicks often show resistance to common depression treatments, making them ideal candidates for investigating alternative therapies. However, demonstrating that a chick exhibits anxiety-like symptoms is crucial to proving that a medication can alleviate such a condition.
“To assert that an anti-anxiety medication reduces an anxiety-like state, the chick, mouse, or rat must experience something similar to human anxiety,” Sufka stated. “While animal behavior in anxiety-like states may vary, it needs to be understood within the context of that animal’s behavior.”
“If I claim to have a drug that alleviates that state, it necessitates establishing that animals have emotional experiences.”
Moreover, this research taps into a deeper and more intricate question: What rights do animals possess? Traditionally, it was thought that animals lack the emotional complexity of humans, which justified lesser needs and rights.
“I argue that all our research supports substantial similarities between avian models and human anxiety and depression, reinforcing the idea that these animals experience negative emotional states,” Sufka explained.
“If this is true, ethically, we must be concerned about animal welfare and ensure they have the best possible living conditions.”
