Background: Feather pecking is a serious behavioral disorder in chickens that has a considerable impact on animal welfare and poses an economic burden for poultry farming. To study the underlying genetics of feather pecking animals were divergently selected for feather pecking over 15 generations based on estimated breeding values for the behavior.
Methods and results: By characterizing the transcriptomes of whole brains isolated from high and low feather pecking chickens in response to light stimulation we discovered a putative dysregulation of micro RNA processing caused by a lack of Dicer1. This results in a prominent downregulation of the GABRB2 gene and other GABA receptor transcripts, which might cause a constant high level of excitation in the brains of high feather pecking chickens. Moreover, our results point towards an increase in immune system-related transcripts that may be caused by higher interferon concentrations due to Dicer1 downregulation.
Conclusion: Based on our results, we conclude that feather pecking in chickens and schizophrenia in humans have numerous common features. For instance, a Dicer1 dependent disruption of miRNA biogenesis and the lack of GABRB2 expression have been linked to schizophrenia pathogenesis. Furthermore, disturbed circadian rhythms and dysregulation of genes involved in the immune system are common features of both conditions.
At first glance I thought this might be satirical. Certainly one thing we share with feather pecking hens is high levels of anxiety.
On a more sociological note it’s quite revealing that for the authors, feather pecking should, not unlike sz, find its ultimate cause not in high levels of anxiety, often associated with bad living conditions, but in their genes. I’m not questioning the role genes play in both these conditions, only the allegedly self-evident nature of the logical primacy of genes over environment when framing causality.
My cat does. She spent three years living in a child’s bedroom before being rehomed to me because the other cats in the home terrorized her. She had bald spots from pulling out her hair when she bathed. She’s still quirky, but she’s got a proper coat again. It’s been almost four years and she is still unwinding from that trauma so far as we can tell.