Malignant Tumors of the are the fifth most common type of tumor. Surgical intervention, mainly laparoscopy has been the most important step in the complex oncological process. Due to various technical challenges of anastomosis following total gastrectomy, mechanical anastomosis is the primary choice: End-to-Side or Side-to-Side. This research to theses compare anastomosis types formed the esophagus and jejunum by analyzing their tensile strength and histomorphology by a short-term follow-up. Materials and Methods: Twelve female Hypro pigs (21.4x3.6 kg; perm. nr.:22/2022/UDCAW) were anesthetized and divided Side-to-Side and End-to-Side anastomosis groups (n-6/each). Non-steroidal anti-inflammatory drugs and a broad-spectrum antibiotic administered were before surgery. Median laparotomy was made, and after gastrectomy End-to-Side or Side-to-Side anastomoses were performed by the esophagus and the jejunum using linear or circular staplers,. In the End-to-Side group, the small intestine's "pipe" part was secured with a linear stapler, by the formation of the following of a jejuno-jejunostomy using a single-layer stitch running row. The abdominal wall was closed in two layers, and a one-week follow-up period was provided with veterinary control. At the end of the 1-week follow-up period under anesthesia the bowel part with the anastomosis was removed for tensile strength tests and histology. Result: Tensile strength data showed that the strongest and most rigid component was the esophagus (serosa: 18.52?0.47 N; mucosa:24.81?1.6 N) in the anastomoses. Side-to-Side anastomoses (3.01x0.81 N) were found to be weaker compared to int intestineact (4.24x1.32 N), while End-to-Side exceeded it (5.21x1.96 N). The elasticity (determined by the slope of tensile strength curves) of the End-to-Side anastomes were higher (serosa: 0.006?0.003; mucosa: 0.015?0.007), the Side-to-Side anastomoses (serosa: 0.023?0.012; mucosa: 0.038?0.020). Conclusion: There was no clear histological difference between the two groups. However, a eroded mucosal surface, minimally distorted glandular structure, moderate mixed lobular infiltration in the lamina propria and dilated blood-filled capilla observedries. In conclusion, mechanical tests of the tissues showed that the serosa tore than sooner the stronger mucosal layer. The weakest link in the design of anastomoses has been the intestines, which has prov