Submitted to: Frontiers in Veterinary Science
Publication Type: Review Article
Publication Acceptance Date: 2/14/2023
Publication Date: 3/16/2023
Citation: Proszkowiec-Wegla, M.K., Kpodo, K.R. 2023. Physiological effects of in ovo delivery of biological substances in broiler chickens. Frontiers in Veterinary Science. 10:1124007. https://doi.org/10.3389/fvets.2023.1124007.
Technical Abstract: The poultry industry has improved genetics, nutrition, and management practices resulting in fast growing chickens; however, disturbances during embryonic development may affect the entire production cycle and cause irreversible losses to broiler chicken producers. The most crucial time in the chicks’ development appears to be the perinatal period, encompassing the last few days pre-hatch and the first few days post-hatch. During this critical period, intestinal development occurs rapidly, and the chicks undergo metabolic and physiological shift from the utilization of egg nutrients to exogenous feed. However, nutrients reserve of the egg yolk may not be enough to sustain the late stage of embryonic development and provide energy for the hatching process. In addition, the modern hatchery practices cause a delay in access to feed immediately post-hatch, and this can potentially affect the intestinal microbiome, health, development, and growth of the chickens. Development of in ovo technology allowing for delivery of active biological substances into chicken embryos during development represents a way to accommodate the perinatal period, late embryo development, and post-hatch growth. Many bioactive substances have been delivered through in ovo technology including carbohydrates, amino acids, hormones, prebiotics, probiotics and synbiotics, antibodies, immunostimulants, and microorganisms with variety of physiological effects. In this review, we will focus on the physiological effects of the in ovo delivery of these substances, including their effects on embryo development, gastrointestinal tract function and health, nutrient digestion, immune system development and function, bone development, overall growth performance, muscle development and meat quality, gastrointestinal tract microbiota development and pathogens exclusion and birds’ metabolism, as well as transcriptome and proteome.