Endpoint titer was defined as the last dilution at which OD405 of the sample wells exceeded the cutoff value (0.1). duodenum contents from two impartial sources were spiked with the egg yolk antibodies, incubated at 42 C for different lengths of time, and subjected to ELISA analysis. The specific IgY titers were dramatically decreased in gizzard contents (up to 2048-fold) but were not changed in duodenum contents. Collectively, oral administration of broiler chickens with the anti-Ent egg yolk powder failed to confer protection against intestinal colonization of is the leading bacterial cause of human gastroenteritis worldwide. Campylobacteriosis is responsible for 400C500 million cases of diarrhea each year; the mortality is usually estimated to be 24 deaths per 10,000 culture-confirmed cases [4].This organism is prevalent in food animals, especially in poultry, posing a significant risk of human infections from farm to fork [5]. Therefore, effective control of in poultry, the primary animal reservoir, would reduce the risk of human exposure to this pathogen and have a significant impact on food safety and public health [6]. colonization in poultry is determined by the factors involved in complex bacterium-host conversation, which generally include bacterial metabolism, virulence, and stress response, as well as chicken immune system and intestinal microbiota, and have yet to be fully elucidated [7]. Over the past decades, the increasing antibiotic resistance due to extensive use of antibiotics in livestock has raised an urgent need to develop nonantibiotic methods, such as vaccines and probiotics [5,8], to control foodborne pathogens, including control in poultry is still highly warranted [5]. Recently, we developed a unique conjugate vaccine targeting enterobactin (Ent) [9], a small siderophore compound utilized by different Gram-negative pathogens, including strains [9,12]. Mouse monoclonal to FGR More importantly, intramuscular immunization of chickens with the Ent conjugate vaccine elicited high levels of systemic anti-Ent IgY, leading to an approximately 3C4 log10 unit reduction of in the intestine, which was consistently observed in two independent trials [13]. However, despite the significant protection of the Ent conjugate vaccine exhibited in this proof-of-concept study [13], it was acknowledged that using an injectable vaccine for control in the poultry production system is not cost-effective. To address this issue, we recently optimized Etimizol conditions for the production of anti-Ent hyperimmune egg yolk IgY using the same Ent conjugate vaccine [14]. We hypothesized that supplementation of chicken feed with the anti-Ent egg yolk powder would control colonization in the chicken intestine. This hypothesis was tested in this study using a well-established chicken model of contamination. Notably, this study, for the first time, assessed the availability and stability of the hyperimmune egg yolk IgY in different segments of the chicken gastrointestinal (GI) tract using both in vivoand ex lover vivo systems. 2. Materials and Methods 2.1. Preparation of the Egg-Yolk-Supplemented Chicken Feed Large quantities of a high titer Etimizol of anti-Ent hyperimmune egg yolks were generated using an Ent conjugate vaccine as detailed in our recent study [14]. In this work, the hyperimmune egg yolks were further lyophilized into powder using a freeze dryer (VirTis AdVantage Plus EL-85 Benchtop Lyophilizer, SP Scientific Inc., Gardiner, NY, USA) following a published protocol [15] with slight modifications. Briefly, the anti-Ent hyperimmune egg yolks were pooled, diluted with Etimizol about half volume of sterile PBS, and homogenized using a sterilized egg whisk. The combination was then transferred into trays with about 500 mL per.
