Immunomodulatory and growth-promoting effects ofroot powder in broiler chicks challenged withGallinarum.

Abstract

BACKGROUND: Amid growing concern about antimicrobial resistance due to the irrational use of antibiotics in treating common poultry diseases, particularlywhich is a foodborne pathogen in humans. This study investigates the effects of ethnoveterinary supplementation of(L. Benth. ex Kurz) powder (RSP) on three key immune-related genes; Suppressor of cytokine signaling 3 (SOCS3), the quiescence-related gene P20K (P20K), and the major histocompatibility complex Class II&#x3b2; (MHC class II&#x3b2;), gut morphology and growth performance of broiler chicks infected withGallinarum. METHODS: Two hundred and forty day-old Hubbard classic chickens were randomly assigned to four groups: non-challenged control (NC), andGallinarum challenge group (SGC), and two treatment groups fed a basic diet supplemented with 1.5%powder (RSP) with SGC (RSP-1) and 3% RSP with SGC (RSP-2), respectively, from day 3 till 28 days of age. Each treatment was replicated 4 times with 15 bird/replicate pen. On day 7, all the birds in the RSP-1, RSP-2 and SGC groups received 1 ml of BHI broth containing 2 &#xd7; 108 CFU ofGallinarum via oral gavage. While control birds received an equivalent volume of sterile BHI broth. Gene expression analysis was conducted using real-time PCR to measure the expression of key immune-related genes: SOCS3, P20K, and MHC Class II&#x3b2; in spleen, liver, and caeca. Additionally, histopathological assessments of gut and growth performance parameters including feed intake, body weight gain, and feed conversion ratio (FCR) were monitored throughout the experimental period. RESULT: The gene expression analysis at 3 and 21 days post-challenge revealed that SGC birds had significantly higher SOCS3, P20K, and lower MHC class II&#x3b2; expression (< 0.001) in the caecum, liver, and spleen of broiler chickens. In contrast, the RSP-1 and RSP-2 groups showed significantly lower SOCS3 and P20K expression (< 0.001), alongside improved gut morphology, weight gain, and FCR compared to the SGC group, with these benefits increasing over time. CONCLUSION: In conclusion, these findings suggest thatsupplementation modulates key immune-related gene expression (SOCS3, P20K, and MHC class II&#x3b2;), enhances intestinal health, and improves growth performance in broilers challenged withGallinarum.