RESUMO
BACKGROUND: The northern pike Esox lucius is a fresh water species belonging to the Esocidae family. It is a carnivorous fish which mostly feeds on invertebrates and fishes. The morphology of its intestine is very useful for understanding the fish's digestive physiology, diagnosing some intestinal diseases and formulating suitable feeds.
OBJECTIVES: This study was designed to determine the anatomical, histological and histomorphometric properties of the intestine of E. lucius.
METHODS: The intestines of five E. lucius were examined in this study. After anatomical dissection, the histological specimens were taken and fixed in 10% formalin. Then, tissue passages were stained with hematoxylin-eosin, and Masson's trichrome.
RESULTS: The anatomical examination showed the short intestine with intestinal coefficient 0.68 +/- 0.09 in E. lucius which is a characteristic of the carnivorous species. The histological study revealed that the intestinal wall of E. lucius is composed of tunica mucosa, submucosa, muscularis, and serosa. The muscularis mucosa was not visible in the intestine. The stratum compactum is present between tunica mucosa and tunica submucosa. The histomorphometric results differentiated between three parts in the intestine of E. lucius namely anterior, middle and posterior. The maximum height of mucosal folds was observed in the anterior intestine due to its role in nutrient absorption. The mucosal fold's height then decreased towards the posterior intestine. The tunica muscularis is significantly thicker in the anterior intestine, and the circular muscle layer is thicker than the longitudinal muscle layer throughout the entire length of the intestine. The posterior intestine possessed large numbers of goblet cells in comparison with other parts of the intestine, to promote elimination of unabsorbed particles.
CONCLUSIONS: The results of this study revealed adaptation for the species feeding habits, so as to protect the intestine and increase absorptive processes
RESUMO
Background and Objective: Several studies reported the immunological activity of Lycium barbarum. This study carried out to determine the effect of aqueous extract of fruits of Lycium ruthenicum L. on morphometric and histomorphometric indices in mice lymphatic organs
Methods: In this experimental study, 36 adult mice were randomly allocated into six experimental and control groups. The experimental groups were received Lycium ruthenicum L. fruit aqueous extract in the doses of 50, 100, 200, 400 and 800 mg/kg/bw, daily by feeding tube for 21 days. In the control group animals were recived 100 mg/kg/bw of saline using feeding tube. After the treatment, the relative increase in the body weight, morphometric, histomorphometric and histopathologic indices in thymus, lymph node and spleen were measured
Results: The administration of extract in doses of 50 and 100 mg/kg/bw did not effect on body weight of mice but in the doses of 200, 400 and 800 mg/kg/bw significantly reduced the body weight [P<0.05].Thymus index in 800 mg/kg/bw of extract significantly reduced in comparison with controls [P<0.05]. Thickness of thymus medulla in low doses significantly increased while it was not visible in higher doses [P<0.05]. Thickness of capsule in lymph node and spleen in dose of 800 mg/kg/bw significantly increased in comparison with control group [P<0.05]. Low doses of the Lycium barbarum extract increased stimulation and infiltration of the immune cells and hematopoiesis in the lymphoid organs while in doses of 400 and 800 mg/kg/bw caused pathological changes including fibrosis in capsule, degeneration in follicles and stromal cell apoptosis
Conclusion: Aqueous extract of fruits of Lycium ruthenicum L. in doses of 400 and 800 mg/kg/bw causes histopathological alterations in the lymphoid organs