Broiler performance correlates with gut morphology and intestinal inflammation under field conditions.

Maintaining optimal gut health is a key driver for a well-performing broiler flock. Histology of intestinal sections and quantification of villus structure can be used to evaluate gut health. While these measurements have been used in experimental models to evaluate gut health, less is known about the associations of these parameters with performance in commercial broiler farms. The objective of the present study was to evaluate possible associations of intestinal villus structure and the inflammatory condition of the gut with Ross 308 broiler performance in 50 commercial farms. On day 28 of the production round, 20 randomly selected broilers per farm were weighed, euthanized, and a duodenal section was collected to determine villus length, crypt depth and the CD3⁺ T-lymphocytes area percentage (CD3⁺ %). We found a relatively low coefficient of variance (CV) for the villus length (between farms; 9.67%, within farms; 15.97%), while the CD3⁺ (%) had a high CV (between farms; 29.78%, within farms; 25.55%). At flock level, the CD3⁺ (%) was significantly correlated with the villus length (r = -0.334), crypt depth (r = 0.523) and the villus-to-crypt ratio (r = -0.480). The crypt depth was significantly correlated with the European production index (EPI) (r = -0.450) and feed conversion ratio (FCR) (r = 0.389). At broiler level, a significant association was found between the individual body weight (day 28), CD3⁺ (%) and villus-to-crypt ratio. These data thus show that gut villus structure is significantly associated with bird performance under commercial conditions. RESEARCH HIGHLIGHTSGut histology parameters vary between and within farms.Broiler performance is associated with gut morphology.