Histological Effects of Different Levels of Sorghum Grain on the Abomasum, Duodenum and Colon of <i>Ghezel×Arkhar-Merino</i> Crossbred Lambs

Abstract

Sorghum grain is comparable to maize in feeding value and can reduce feed cost and dependency on maize. Sorghum grain containing reasonable amounts of tannin which have ability to bind dietary protein, carbohydrate and minerals. Consuming high amounts of tannins may cause bowel irritation on gastrointestinal tissues. The objective of this study was to assess the effect of replacement of different levels of barley with sorghum grain on histological changes of the abomasum, duodenum and colon. In this study sixteen male Ghezel×Arkhar-merino crossbred lambs were used. Dietary treatments had same amounts of alfalfa hay (20% total DM) and different levels of the barley grain substituted with sorghum grain in which sorghum grain was used in the levels of 0, 60, 70 and 80 percent of total ration. Lambs were randomly assigned to one of the four dietary treatments in a completely randomized design assignment. At the end of finishing period the lambs were slaughtered and samples were prepared. The gross examination of abomasum, duodenum and colon did not reveal any significant necropsy signs. Samples were preceded by routine histological techniques and H and E staining method. Histological results showed that, abomasum has not distinct histological damage; except increasing of parietal cells and lymphocytosis in lamina propria and tunica submucosa. The presence of lymphocytosis probably is not related to the sorghum usages. microscopic observations of duodenum and colon showed that, higher dietary sorghum grain resulting histological changes as increase of goblet cells, dilatation of lumen of Lyberkohn's glands in order to degeneration of apical parts and brush borders of secretory units surface cells and degeneration of apical parts of villi surface cell. Also hyperemia and sporadic hemorrhage was observed in lamina propria and tunica submucosa of duodenum and colon in high level sorghum diet.