Histomorphological and mucin histochemical study of the alimentary canal of pangas catfish, Pangasius pangasius (Hamilton 1822)

The present study describes the histological and mucin histochemical properties of the alimentary canal (AC) of the pangas catfish, Pangasius pangasius. The results revealed that the mucosa of the oesophagus was lined by a stratified epithelium containing chloride cells and taste buds which suggested mechanic, gustatory and physiologic roles of the oesophagus in this species. The stomach mucosa was lined by a simple columnar epithelium. The lamina propria-submucosa in cardiac and fundic stomach contained gastric glands. The pyloric stomach had the thickest muscularis layer among all the parts of the AC. The villi showed the maximum height and width in the middle intestine. The tunica muscularis and serosa showed the thinnest thickness among all parts of AC. The mucin histochemistry showed that the goblet cells of oesophagus and intestine contained both neutral and acidic with carboxylated and sulfated mucins and there was not acidic mucins in epithelial cells of the stomach

Evaluation of morphologic method for the detection of nervous tissue in minced meat

Producing meat products with ingredients which are not consistent with the label is considered fraud. Due to the high economic value of meat, the use of unauthorized tissue in meat products is possible. Aside from the adulteration aspect, it is important to note that some animal tissues like the brain and the spinal cord can bear infective agents which are transmissible to humans. Based on these observations, the aim of the present study was to apply morphological method for detection of nervous tissues in minced meat. Laboratory adulterated minced beef meat; each containing 0, 5, 10, 15 and 20% of beef brain was prepared. Then each sample was divided into three parts and four paraffin embedded blocks were prepared from each part. The sections were stained using sudan black and cresyl violet and also the immunohistochemical staining with fluorescent method were applied using anti-neurofilament 200 antibody for the determination of nervous tissue. Although the neuronal cell bodies and neuronal fibers were clearly detectable in Cresyl violet staining and sudan black staining, respectively, however, staining intensity did not show any difference according to different percentages of added brain. In contrary, immunohistochemical study revealed that neurofilament 200- immunolabeling was present in all percentages of added brain samples and the intensity of the labeling varying from weak to strong consisted by the increasing the amount of brain in samples. In conclusion, the immunohistochemical technique with fluorescent method is an effective method for evaluations of additive brain tissue in minced meat with high sensitivity