Prenatal auditory stimulation induces physiological stress responses in developing embryos and newly hatched chicks

Multilevel sensor for monitoring external and internal environment of eggs

“… Donofre et al (2018) , when exposing eggs to environments with 70 and 90 dB, also pointed out that, in addition to sound pressure levels varying according to the internal content of the egg, shell insulation also varies according to the external volume applied. The results of this study therefore reinforce that the eggshell is a barrier to sound, but the embryo is still exposed to a fraction of the sound present in the external environment, which can impact its development ( Hanafi et al, 2023 ). However, more in-depth studies in bioacoustics are necessary to investigate the propagation of sound waves in a complex and closed structure, such as the egg.…”

“…Results indicate, therefore, that external lighting influences the interior of eggs, as the composition of the eggshell does not represent a complete barrier against the passage of light. Therefore, although several studies have focused only on external lighting and the consequent impact on embryogenesis success ( Tong et al 2018 ; Li et al, 2021 ; Hanafi et al, 2023 ), recent studies already indicate that the composition and color of the shell also play a role in influencing the hatchability of eggs. Orellana et al (2023) , for example, observed that less translucent eggshells showed a higher percentage of hatchability (6.9% more) with chicks weighing 0.7 g heavier when compared to more translucent eggs.…”

“…( Amjadian and Shahir, 2020 ; Tona et al, 2022 ). However, breaking a paradigm that only temperature and humidity are sufficient for successful incubation, recent literature has reported that other environmental stimuli can impact bird embryogenesis ( Abdulateef et al, 2021 ; Hanafi et al, 2023 ).…”

“…The auditory system of birds is one of the first to develop, functioning since the 10th embryonic day ( Tong et al, 2013 ). Considering this, studies have explored how different sounds influence cognition, learning, memory and neuronal development of chicks in the first days after hatching ( Kesar, 2014 ; Donofre et al, 2020 ; Hanafi et al, 2023 ).…”

Impacts of Maternal Noise Exposure on Risk of Stillbirth and Oxidative Stress-Induced Neurobehavioral Changes in Offspring

“…There is also evidence that maternal stress during pregnancy increases lipid peroxidation (LPO) in the offspring's postnatal brain, suggesting that redox balance in the brain may be altered for a long time after the baby is born [30]. Liegelin Kavitha Bernhardt et al reported that prenatal stress increased oxidative stress, including increased malondialdehyde (MDA) levels, reduced glutathione (GSH), superoxide dismutase (SOD), and total antioxidant activity (TAO), while glutathione reductase (GSS-Rd) levels remained low in offspring's brain [31].…”