Cholecystokinin induces crowing in chickens.

Area of Science:

• Neuroscience
• Animal Behavior
• Molecular Biology

Background:

• Most animal vocalizations are innate, unlike human vocal learning.
• The molecular mechanisms underlying innate vocalization remain largely unknown.
• Rooster crowing is an innate behavior controlled by the midbrain nucleus intercollicularis (ICo).

Purpose of the Study:

• To identify the molecular basis of innate vocalization in roosters.
• To investigate the role of the cholecystokinin B receptor (CCKBR) in rooster crowing.

Main Methods:

• RNA sequencing was used to compare gene expression in the ICo of roosters that crow versus those that do not.
• Gene and neurotransmitter expression (CCKBR and cholecystokinin (CCK)) in the ICo were analyzed.
• The effect of CCKBR agonist administration on crowing behavior was examined.

Main Results:

• CCKBR expression was significantly upregulated in testosterone-treated groups that exhibited crowing.
• Both CCKBR and its ligand CCK were expressed in the ICo.
• Administration of a CCKBR-specific agonist induced crowing behavior.

Conclusions:

• The cholecystokinin system, mediated by CCKBR, plays a crucial role in inducing innate vocalization (crowing) in roosters.
• This study identifies CCKBR as a key regulatory gene in the neurobiology of innate vocalization.
• Findings contribute to understanding the molecular underpinnings of species-specific vocal behaviors.