Zoonotic diseases are diseases that are transmitted from animals to humans and vice versa. Pseudomonas aeruginosa (P. aeruginosa) is a pathogen with zoonotic nature. Commercial poultry could be infected with P. aeruginosa, especially at young ages with great losses. Infection of embryos with P. aeruginosa induced death in the shell, while infection of chicks led to septicemia, respiratory and enteric infections, and high mortality. Humans are also highly susceptible to P. aeruginosa infection, and the disease is associated with severe lung damage, especially in immunocompromised patients. Chicken carcass and related poultry retail products play an important role in the transmission of P. aeruginosa to humans, especially after processing in abattoirs. Treatment of P. aeruginosa infection is extremely difficult due to continuous development of antibiotic resistance. The transfer of antibiotic-resistant genes from poultry products to humans creates an additional public health problem. Accordingly, this study focused on avian pseudomonad, especially P. aeruginosa, with respect to infection of poultry, transmission to humans, and treatment and antibiotic resistance.

SUMMARY Nanotechnology is an innovative promising technology that has a great scope of applications as well as a socio-economic potential in poultry industry sector. Nanoparticles (NPs) show advantages of high absorption and bioavailability with more effective delivering to the target tissue compared to their bulk particles. Nanomaterials show variable forms, sizes, shapes, applications, surface modifications, charges and natures. Top-down and bottom-up methods are the common types of NPs preparation. There are different mechanisms through which NPs could exert their action. In the poultry field, NPs have been considered in diagnosis of many diseases using different techniques, vaccines preparations and immuno-stimulation, disinfection, production enhancement, detection of food adulteration and antimicrobial activities (antiviral, antibacterial, antiparasitic, antifungal) and antimycotoxins. As a result of enhancement of poultry production and reducing the bacterial load after using NPs, the antibiotics drug resistance obstacle can be overcome. Despite the wide benefits of using NPs in poultry production, some concerns about their safety and hazardous effects should be regarded. Therefore, this review article is focused on NPs’ types, manufacture, mode of actions, and different applications with reference to safety and hazards impact.

Poultry industry has been recognized as a fast-developing sector aiming to produce low-cost and high-nutrient foods for human consumption. This review article aimed to focus on the significant roles of dietary betaine supplementation in the poultry industry. In this respect, different effects of betaine on performance and carcass traits, as well as its osmoregulatory, anticoccidial, immune-modulatory, and heat-stress alleviation activities, were discussed. Different concentrations of betaine supplementation can improve the feed conversion ratio, final body weight, breast muscle yield, egg production ratio, and reduce body fat contents in broiler chicken, turkey, duck, geese, and quail diets. Betaine supplemented with methyl groups can eliminate the need to have some methyl-group donors, including choline and methionine, therefore having positive effects on feed conversion ratio in poultry diets. The osmolytic character of betaine can alleviate heat stress and have a positive impact on tonic immobility, which consequently reduces stress in poultry. By inhibiting distinct developmental stages of Eimeria species, betaine reduces the damaging effects of coccidiosis on broiler chickens and improves intestinal structure and function. The immunological, cardiovascular, neurological, renal, and hepatic metabolic systems benefit from betaine’s osmo-protective properties. Therefore, betaine has the potential to be considered as an alternative to feed additives and enhances the health status and productive performance of poultry.

Feed additive antibiotics have been used for many decades as growth promotors or antibacterial substances worldwide. However, the adverse impacts of using antibiotics in animal or poultry feeds are not widely recognized. Therefore, the search for alternatives, such as probiotics, prebiotics, phytobiotics, post-biotics, bacteriophages, enzymes, essential oils, or organic acids (OAs), has become urgent. OAs are produced by beneficial intestinal bacteria through the fermentation of carbohydrates. OAs and their salts are still used as feed preservatives. They have long been added to feed in order to minimize contamination and the growth of harmful bacteria and fungi, reduce deterioration, and prolong the shelf life of feed commodities. Moreover, they have been mostly added to poultry feed as a blend to obtain maximal beneficial effects. The supplementation of poultry with OAs could improve the growth performance parameters and carcass traits, promote the utilization of nutrients, boost the immune response, and inhibit the growth of pathogenic bacteria. Therefore, this review article provides valuable insights into the potential benefits of using OAs in reducing microbial load, enhancing performance parameters in broilers and layers, improving gut health, and boosting the immune response.

With the high rise of drug resistance in microbial populations, there has been a surge in researches to find new natural antibiotics alternative compounds that can be used safely in both humans and animals. The main goals of using this category of alternatives are maintaining the gut microbiome in healthy conditions and preventing the attachment of pathogenic organisms at the early life stages. Probiotics, prebiotics, and synbiotics have been widely used for several years as growth promoters and as preventive measures against several enteric pathogens with successful results. Recently, paraprobiotics and postbiotics are derivatives of probiotic cultures and have been used in humans, animals, and poultry. They are regarded as immunostimulators, anti-inflammatory, antioxidants, and anti-microbial, as well as growth promoters. Till now, there is scanty information about the use of paraprobiotics and postbiotics in animals or in the poultry sector. Accordingly, this review article has focused on defining these new categories of natural alternatives with descriptions of their types, functions, and uses, especially in the poultry field. Keywords: Immunomodulation, Paraprobiotics, Performance, Postbiotics, Poultry.