Microhandling of vesicular glutamate uptake modulate feeding in broilers.

Glutamate (Glu), the major excitatory neurotransmitter in vertebrate central nervous system, is actively taken up and stored in synaptic vesicles. On the arrival of an action potential to the pre-synaptic membrane and the subsequent opening of the voltage-gated calcium channels and movement of Ca(2+) into the neuron, these small vesicles fuse with the pre-synaptic membrane to release the neurotransmitter content into the synaptic cleft. Because it has previously been shown that intracerebroventricular (ICV) glutamate plays a role in feed intake in broilers, the manipulation of its vesicular concentration could affect feeding behaviour. On the contrary, research on vesicular glutamate transporters has, so far, been carried out on mammalian species. In the present study, we aim to examine the effect of Chicago sky blue 6B (CSB6B), a glutamate vesicular uptake inhibitor, on feed intake and latency to start feeding in a commercial strain of meat type chickens. To do this, four experiments have been designed to investigate the effect of ICV injection of saline, glutamate, as a general agonist for glutamate receptors, CSB6B and the combination of Glu and CSB6B. The findings indicate that CSB6B increases feed intake and decreases the latency to start feeding in 24-h-feed-deprived Ross 208 broilers.