Postnatal small intestinal morphological development in Cobb 500 broiler chickens

Intestinal development in broiler chickens is crucial for nutrient absorption for growth. Indices like villus height, crypt depth, villus perimeter, and villus area reflect the nutrient absorptive capacity of birds. Hence, this study investigated postnatal small intestinal maturation in Cobb 500 broiler chickens. On d 0, birds were randomly assigned to 16 replicate cages of 8 birds per cage with body weight (BW) as a blocking factor. Jejunal and ileal tissues were collected from one bird per cage on d 0, 7, 14, 21, and 28 for intestinal morphology measurements. Data were analyzed using the MIXED procedure of SAS. A 5 × 2 factorial arrangement was used, with age (0, 7, 14, 21, and 28 d) and intestinal section (jejunum and ileum) as the two factors. There was a positive linear effect of age (P < 0.01) on villus height, villus perimeter, and villus area. There was a quadratic effect of age (P < 0.01) on villus base width, villus mid-width, crypt depth, and villus height to crypt depth (VH/CD) ratio. The villus height, villus area, and VH/CD ratio were greater (P < 0.05) in the jejunum relative to the ileum. There was a linear effect of age (P < 0.01) on luminal area, total cross-sectional perimeter, and total cross-sectional area of broiler chickens. Villus height, perimeter, and area were strongly positively correlated with other intestinal morphology indices in the jejunum and ileum (P< 0.01), except for ileal total cross-sectional area. All intestinal morphological indices exhibited a slower growth rate relative to BW from d 7 to 28. In conclusion, this study reveals coordinated structural changes in the intestinal mucosa that are likely important for supporting the rapid postnatal growth and provides a baseline for age-related intestinal maturation as well as a framework for future studies aimed at linking morphological development with nutritional strategies in broiler chickens.