Role of Physiology, Immunity, Microbiota, and Infectious Diseases in the Gut Health of Poultry

Abstract

“Gut health” refers to the physical state and physiological function of the gastrointestinal tract and in the livestock system; this topic is often focused on the complex interacting components of the intestinal system that influence animal growth performance and host-microbial homeostasis. Regardless, there is an increasing need to better understand the complexity of the intestinal system and the various factors that influence gut health, since the intestine is the largest immune and neuroendocrine organ that interacts with the most complex microbiome population. As we face the post-antibiotic growth promoters (AGP) era in many countries of the world, livestock need more options to deal with food security, food safety, and antibiotic resilience to maintain agricultural sustainability to feed the increasing human population. Furthermore, developing novel antibiotic alternative strategies needs a comprehensive understanding of how this complex system maintains homeostasis as we face unpredictable changes in external factors like antibiotic-resistant microbes, farming practices, climate changes, and consumers’ preferences for food. In this review, we attempt to assemble and summarize all the relevant information on chicken gut health to provide deeper insights into various aspects of gut health. Due to the broad and complex nature of the concept of “gut health”, we have highlighted the most pertinent factors related to the field performance of broiler chickens.

Bioactive compounds, antibiotics and heavy metals: Effects on the intestinal structure and microbiome of monogastric animals – a non-systematic review

“…The imbalance of the intestinal microflora due to the abuse of antibiotics, a deficiency of nutrients and/or an infection with the protozoans Eimeria spp. is associated with the growth of and colonisation by Salmonella and Clostridium strains in the gastrointestinal tract, which increases the susceptibility to various types of diseases (Madlala et al, 2021;Wickramasuriya et al, 2022). The infection with Eimeria destroys the cells of the epithelial barrier, which increases intercellular permeability and the outflow of nutrients and impairs the digestion and absorption of proteins (Leung et al, 2018;Nabian et al, 2018).…”

Food Industry Byproducts as Starting Material for Innovative, Green Feed Formulation: A Sustainable Alternative for Poultry Feeding

“…While the productivity of broiler chicken is now higher than ever, thanks to genetic selection, improved animal nutrition, management, and dietary supplementation with antibiotics [ 7 ], poultry represents a threat to human health, especially as a vector of infectious diseases and because of its role in the development of antimicrobial resistance [ 8 ].…”

“…Thus, the sustainable productivity of the meat industry hinges on the discovery and development of novel dietary supplements that could mimic antibiotic growth promoters, among which prebiotics, probiotics, synbiotics, organic acids, essential oils, antibodies, enzymes and phytogenic feed additives can be enumerated [ 8 ]. The addition of these natural extracts can be useful for the growth performance of broilers since it does not negatively affect animal health or the quality of animal products for human consumption [ 9 ].…”

Comparative Analysis of Gut Microbiota Between Healthy and Diarrheic Horses

“…Mammal intestines contain more than 10 14 microorganisms including bacteria, fungi, viruses, and protozoa, which are approximately 10 times the total quantity of host cells and play crucial roles in intestinal physiological function, metabolism, and host health ( 1 – 3 ). Furthermore, increasing evidence indicated that gut microbiota also functions in epithelial differentiation, intestinal homeostasis, and immunity ( 4 , 5 ). Early investigations demonstrated that the consistency of the gut microbial community is the precondition for conducting digestive absorption and complicated metabolic functions, whereas gut microbial dysbiosis is closely related to many diseases ( 6 – 8 ).…”