Poultry meat is one of the main sources of animal protein globally and this category is associated with human entero-pathogens Salmonella and Campylobacter. The management and/or prevention of these bacteria is multi-facet from farm to fork. Feed withdrawal (FW) time of meat chickens is an on-farm intervention to reduce gross and entero-pathogen contamination. The current practice of 8-12 hours FW is to ensure caecal emptying and intestinal integrity thus minimising intestinal rupture during processing. A controlled seeder bird challenge (10⁵ CFU/mL) study investigated the effect of FW on the modern Cobb 500 meat bird at 2-hour intervals for 24 h. Anatomical gross gut (intestine integrity score, tensile strength) morphology showed no real change. The significance of a transient improvement in intestine tonicity at 14 and 16 hours is unclear but interesting. Histologically, the ileum observed a subtle change in gross diameter and increases of villi height and crypt depth with FW. Caecal microbiome was investigated by classical enumerations of entero-pathogens and 16SrRNA analysis. Populations of caecal Campylobacter remained stable (10⁸ CFU/g at 100% prevalence), throughout FW, whereas, Salmonella populations were at low levels (10² CFU/g) in caeca and did not change with FW. There was a higher prevalence of Salmonella seen in 16SrRNA as compared to cultural methods. The microbiota changes seen by 16SrRNA analysis are subtle but do demonstrate increases in the proportion of two families of bacteria Bacteroidaceae and Enterobacteriaceae and the decrease in Lachnospiraceae and Lactobacillaceae over FW time.