Effects of in ovo injection of metabolic stimulants and L-carnitine in broiler hatching eggs on subsequent chick hatchability, growout performance and tissue nutrient profiles

In the first phase of the current study, metabolic combinatorial solutions were in ovo administered in broiler eggs on Day 18 of incubation to investigate their effects in broiler chick tissue nutrient profiles until Day 10 of posthatch growout. In the second phase, the effects of in ovo injection of L-carnitine on Day 18 of incubation in broiler eggs were examined. The treatment solutions used in these studies were considered to play significant roles in various biochemical pathways, and were hence tested to determine whether they could potentiate the physiological growth and development of the broiler embryos and posthatch chicks. The in ovo injection of treatment solutions in both trials did not produce any significant increase in performance or slaughter yield in broiler chicks. However, positive trends were determined for rate of hatch and tissue nutrient profiles, which implied that the in ovo administration of nutrient supplements may be supportive of embryonic development and posthatch growout performance

Impaired Recall of Positional Memory following Chemogenetic Disruption of Place Field Stability

The neural network of the temporal lobe is thought to provide a cognitive map of our surroundings. Functional analysis of this network has been hampered by coarse tools that often result in collateral damage to other circuits. We developed a chemogenetic system to temporally control electrical input into the hippocampus. When entorhinal input to the perforant path was acutely silenced, hippocampal firing patterns became destabilized and underwent extensive remapping. We also found that spatial memory acquired prior to neural silencing was impaired by loss of input through the perforant path. Together, our experiments show that manipulation of entorhinal activity destabilizes spatial coding and disrupts spatial memory. Moreover, we introduce a chemogenetic model for non-invasive neuronal silencing that offers multiple advantages over existing strategies in this setting