Effects of Diamond V Original XPC™ on modulating adaptive immune function in broilers

This study was conducted to investigate the effect of Diamond V Original XPC (XPC), a broad spectrum immune modulator, on immune function in broilers. One-day-old broilers were randomly assigned one of two treatments: 1.25 kg/ton XPC (T1), or control diet (T2). All broilers were vaccinated for Newcastle disease virus (NDV) on d1 (B1 strain) and d21 (LaSota strain) via eye drop.

Body weight, feed consumption, feed conversion ratio, and mortality were recorded to monitor growth performance. There was no significant difference in body weights (P < 0.05) between T1 and T2. Due to only one pen per group, no statistical analysis was conducted for feed consumption or feed conversion. Blood and immune organ samples (thymus, bursa of Fabricius, and spleen) were collected to evaluate immune system development on days 14, 21, 28, 35 (blood only), and 42.

Birds supplemented with XPC had significantly greater thymus indices on days 28, and 42. Birds in T2 had significantly greater bursa of Fabricius indices on days 14 and 42, and a significantly greater spleen index on d21. The result of NDV antibody titer measurement showed the Immunoglobulin G level of T1 was significantly higher than T2 after 1st vaccination on day 14, and increased faster than T2 after boost on day 21. Cell proliferation results from blood had the same trend with NDV antibody titer results; T1 had significantly stronger T-lymphocyte abilities than T2 at d28. Through histology observation, there was no significant difference in the thymus medulla and cortex ratio between T1 and T2. In the spleen, T1 contained significantly more white pulps at d14 than T2. These results demonstrate that XPC supplementation influenced broiler immune system development at an early stage.

Key Words: XPC, Immune function, antibody titer, spleen, thymus