Performance, Intestinal Health, Cecal Microbiota and Nutrient Transporter Genes Expression between Arian and Ross Broiler Chickens under Wheat-Based Diets

Abstract

This experiment examined the responses of Arian and Ross broiler strains to wheat-based diets formulated with elevated levels of meat meal, intended to disrupt gut health and induce dysbiosis. The objective was to evaluate strain-dependent resilience and determine the extent to which gut health promoting feed additives could mitigate potential genetic predispositions to intestinal dysfunction. Six dietary treatments were administered: the basal diet without additives (control) and the basal diet supplemented with either an antibiotic, probiotic, prebiotic, organic acid, or phytobiotic. Evaluated parameters included growth performance traits, carcass weight, organ weights, intestinal length, clinical and histological indicators of intestinal health, and gut microbial populations. Additionally, the expression of key nutrient transporter-related genes (SLC7A5, SLC7A6, SLC7A9, SLC6A19, GLUT2, and SI) were quantified. The Ross strain exhibited significantly(p<0.05) higher feed intake than the Arian strain (4543 g vs. 3977 g), a superior feed conversion ratio (1.66 vs. 1.76), higher live weight (2713.2 g vs. 2232.3 g), carcass weight (2030 g vs. 1637 g) and also intestinal length (226.1 mm vs. 202.9 mm). Despite the potentially challenging nature of the basal diet, no significant differences in dysbacteriosis or necrosis scores were observed between the two strains (p>0.05), indicating effective adaptation in both strains. The microbial populations of Escherichia coli, Lactobacillus, and Clostridium perfringens were significantly higher in Ross birds than Arian (p<0.05). Among diets, the phytobiotic-supplemented diet significantly upregulated the expression of SLC6A19, SLC7A5, and SLC7A6 genes in the Ross strain (p<0.05). While organic acids significantly enhanced SLC7A6 expression in both strains, antibiotics significantly upregulated SLC7A9 in the Ross strain. The expression of GLUT2 was not significantly affected by genetic strain (p>0.05). These findings suggest that the improved performance of Ross 308 broilers, particularly under phytobiotic supplementation, may be partially attributed to enhanced expression of nutrient transporter genes in response to intestinal challenge.