Domestic animals have a lower stress response compared to their wild ancestors. So far our research has shown that there is no single gene responsible for this change. Rather, there is a large number of genes that each have a minute effect on the stress response.

My research is focused on discovering and mapping the genes responsible for the lowered stress response in domestic White Leghorn chickens as compared to their wild Red Jungle Fowl ancestors. However this has proven to be difficult as there is no "master stress gene". Rather than an expression of critical steroidogenic genes, there is a number of genes whose lowered expression affects the stress response.

These results are based on a primary study measuring five classes of steroids (Pregnanens, Progestines, Glucocorticoids, Androgens and Estrogens) using liquid chromatography tandem mass spectrometry methods (LC-MS/MS), before, 10 min after, and 60 min after a standardised stress situation, in White Leghorn and Red Jungle Fowl chicks. The subjects where then subjected to microarray analysis of gene expression in adrenal glands, which showed a significant breed effect in a large number of transcripts.

We have found QTL regions involved in the modifications of the stress response, generated during chicken domestication. Our results specifically suggest that SERPINA10 may be a strong candidate gene affecting the differences between ancestral Red Junglefowl and domesticated White Leghorn chickens.

Further analysis showed that many of the candidate genes in this study were located in homologous regions that were previously reported as main QTL for CORT response in rats and pigs, suggesting the importance of these genomic region in stress response. Currently we are attempting to narrow down the QTL for ALdosteron and DHEA to the constituent casual genes, something that has never been done in any studied species.

Background and aspirations

My interest in animal behaviour began in veterinary college, which I attended in Garmsar, Iran. I have always been interested in psychology, and, once I obtained my degree, I studied and obtained a second master's degree, in Ethology, which is a bit like animal psychology.

My then thesis advisor, professor Per Jensen of the AVIAN Behavioural Genomics and Physiology group at Linköping University, kindly informed me of the Ph.D. positions made available at the time and I managed to secure one of them. As I finish my thesis I hope to apply for an international post-doc grant which would enable me to continue my work from Linköping University while expanding my research network in the USA.



Amir Fallahshahroudi

Domestication Effects on the Stress Response in Chickens: Genetics, Physiology, and Behaviour

Doctoral thesis, comprehensive summary

Amir Fallahsharoudi, Neil de Kock, Martin Johnsson, Lejla Bektic, S J Kumari A Ubhayasekera, Jonas Bergquist, Dominic Wright, Per Jensen

QTL mapping of stress related gene expression in a cross between domesticated chickens and ancestral red junglefowl.

In Molecular and Cellular Endocrinology

Article in journal

Amir Fallahshahroudi, Neil de Kock, Martin Johnsson, Lejla Bektic, S J Kumari A Ubhayasekera, Jonas Bergquist, Dominic Wright, Per Jensen

Genetic and Targeted eQTL Mapping Reveals Strong Candidate Genes Modulating the Stress Response During Chicken Domestication.

In G3

Article in journal