Morphology of the Gastrointestinal Tract and its Lymphoid Tissue in the Common Blackbird (Turdus merula)


  • Nadiya Dyshliuk National University of Life and Environmental Sciences of Ukraine, Faculty of Veterinary Medicine, Ukraine
  • Svitlana Huralska Polissia National University, Faculty of Veterinary Medicine, Ukraine
  • Tetiana Kot Polissia National University, Faculty of Veterinary Medicine, Ukraine
  • Tetiana Mazurkevych National University of Life and Environmental Sciences of Ukraine, Faculty of Veterinary Medicine, Ukraine
  • Zhanna Stehnei National University of Life and Environmental Sciences of Ukraine, Faculty of Veterinary Medicine, Ukraine
  • Svitlana Usenko National University of Life and Environmental Sciences of Ukraine, Faculty of Veterinary Medicine, Ukraine


birds, esophagus, stomach, intestine, lymphoid nodules


The paper presents results of a microscopic study of the wall of the esophagus, stomach, and intestine and their lymphoid tissue in birds of the blackbird species. The material was selected from 10 adult blackbirds. It was embedded into paraffin according to the conventional method. The results of the study revealed that the general structure of the tunics of the esophagus, stomach, and intestine in the blackbird is similar to other birds, but exhibits certain characteristics. In the mucosa and submucosa of these organs, lymphoid tissue is noted, which is represented by different levels of structural organization. “Lymphocyte tracks” in the form of small diffuse lymphoid tissue cords are observed in the esophagus. Small accumulations of diffuse lymphoid tissue are also found in the muscular stomach. Solitary lymphoid nodules in the glandular stomach were found not only in the mucosa but also in the subserosa of the serosa. The largest accumulations of lymphoid tissue are observed in the esophageal and cecal tonsils and aggregated lymphoid nodules of the intestines, which are areas of significant penetration of antigens into the body of birds. In the places where they are located, infiltration of surface epithelium and crypts by lymphoid cells is observed. The smallest area of these immunocompetent structures is occupied by diffuse lymphoid tissue and much larger – by lymphoid nodules. The results of the research allowed to assess the morphofunctional status of lymphoid formations in the organs of the digestive canal of the blackbird and, accordingly, to determine the state of their immune system.


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Animal Science