Fixation is a crucial step in processing of tissue specimen for preservation of cellular architecture and composition of cells. Alcohol-based fixatives are considered some of the most promising alternatives to formalin. We evaluated the performance of alcohol-based fixatives (EthMeth and methacarn) and formalin as a comparator fixative in the research laboratory. Following 24 hours of fixation, tissue morphology and cellular details of the liver, spleen and brain (cerebral cortex) were evaluated. Morphological characteristics were evaluated by gross observations and analyzing cellular details, tissue architecture and overall staining characteristics (Hematoxylin and Eosin). EthMeth and methacarn fixation gave generally comparable and satisfactory results on the tissue morphology and subsequent identification of tissue characteristics. Particularly, tissues were well preserved and all nuclear as well as cytoplasmic details were clearly visible. However, formalin fixed tissues showed some peculiarity such as improper fixation, mild shrinkage, and alterations of tissue components. These results confirm that alcohol-based fixation is the superior alternative to formalin for preservation of tissue morphology. However, it is required to standardize the formalin-free methods and harmonize diagnosis in the laboratory worldwide.

Native chickens of Bangladesh are scavenging in nature. In our previous studies, we have histologically and immunohistochemically examined the ontogeny of lymphoid organs of native chickens of Bangladesh in prenatal stages. To date, the study on gross anatomical development of prenatal lymphoid organs is lacking. In the present study, detailed macro-anatomical development of prenatal lymphoid organs of native chickens were examined during different embryonic stages of development, which was conducted in the laboratory of the department of Anatomy and Histology, Bangladesh Agricultural University. In the present study, thymus was first identified by the 10 days of incubation (ED 10) as a chain at the both side of the neck. Bursa of Fabricius and spleen were also first found to develop at ED 10. While comparing with the prenatal development of lymphoid organs of native chickens with that of previously studied hybrid chickens, the native chickens' lymphoid organs were found to develop earlier. Taken together with our previous results, the developmental trajectory data of the present study are first to clarify that the immune system of native chickens are being prepared earlier to face the scavenging environment after hatching.

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The plant Aganosma dichotoma is widely used as traditional medicine in different aborigines which is supported by this investigation. It belongs to Apocynacae family. The aim of the study was to evaluate the methanolic extract of leaf of Aganosma dichotoma's different fractionates as anti-diarrheal agents. The methanolic extract of leaves of Aganosma dichotoma (400 mg/kg) exhibited very statistically significant anti-diarrheal activity with a 68.27 % reduction of diarrhea compared to the standard of loperamide 69.23 %. The anti-diarrheal activity shows Aganosma dichotoma statistically significant at the higher dose compared to dose of 200 mg/kg. Therefore we can assume that, the anti-diarrheal activity of Aganosma dichotoma was dose dependent.