Abstract:Immuhischemistry (IHC) and semi-quantitative RT-PCR were used to study the distribution and expression of gonadotropin-inhibitory hormone (GnIH) in the digestion and respiratory system of 30-day-old Luchuan male piglets in this research.The IHC results showed that the GnIH immune positive cells distributed in both digestion and respiratory system,such as torus pyloricus,duodenum,ileum,colon,liver,esophagus,filiform papillae,submandibular gland and trachea,but the GnIH-ir cell morphology and sizes were diverse.The results of semi-quantitative RT-PCR suggested that the GnIH mRNA was moderately expressed in the colon and submandibular gland,lowly expressed in the torus pyloricus,filiform papillae and ileum,and not expressed in the other organs.