Validity of pig lung culling by veterinary rules of animal slaughter NO. 68718 DATED 06/02/2022

Abstract

The purpose of the study is to determine the validity of culling of pigs with morphological changes that occur when stunned before slaughter by carbon dioxide, according to Veterinary Rules of animal slaughter No. 68718 02.06.2022. As the research material, lung samples of 8 healthy slaughter pigs aged 6.5-7.5 months, weighing 95-105 kg, including 3 pigs stunned by electric shock, and from 5 pigs that were stunned by carbon dioxide were used. The samples were fixed in a 10% solution of neutral formalin. Histological sections were made, they were stained with hematoxylin and eosin. In the lungs of 3 pigs, which were stunned with electric shock and then exsanguinated, during post-slaughter examination, a uniform staining of the organ in light red color, elastic consistency was established, which corresponded to a normal lung. In the lungs of 5 pigs, which were stunned with carbon dioxide and then exsanguinated, heterogeneous staining was established during post-slaughter examination; there were areas of dark red color and compacted consistency, frothy liquid was released from the surface of the incision. In histological preparations of the lungs of pigs that were stunned with carbon dioxide, edema of the alveoli and congestive hyperemia of blood vessels were detected, which should be recognized as the result of insufficient exsanguination. In histological preparations of the lungs of pigs, which were stunned with electric shock, fullness of blood vessels and pulmonary alveolar edema were found. The rules of veterinary and sanitary examination do not indicate the culling of lungs with hyperemia and edema, that is, they are not subject to disposal and destruction. Assuming the exact execution of directive documents and careful treatment of animal slaughter products, it makes sense to officially recognize such lungs as either subject to destruction or suitable for a certain use.