The hazardous effects of formalin and alcoholic fixative in mice: A public health perspective study.

Formalin is used for different purposes due to its preservation capability. But continuous exposure to formalin may result various health related issues leading to cancer and death. A new alcohol-based fixative, EMA (ethanol, methanol and acetic acid = 3:1:1) could be a safer option in this regard. To compare the health hazards of formalin and EMA, a total 15 adult male mice were randomly distributed into three groups- exposure groups (formalin and EMA) and control group. The mice were subjected to natural inhalation exposure of the fixatives followed by behavioral depression test (forced swimming test), histopathology and serum biochemical tests. Our results showed that the hazardous effects of formalin were remarkably higher than that of EMA. Formalin exposed group showed severe depression (P < 0.001) in the forced swimming test compared to EMA and control groups. Histopathologically, diffuse lymphocytic infiltrations around the lung alveoli and bronchioles and severe inflammation with accumulation of reactive cells in the cerebral cortex were detected in the formalin exposed group, whereas little or no inflammation with fibrinous exudates in the bronchioles was reported in the EMA group and no inflammatory cells were detected in the cerebral tissues. The serum biochemical analysis of the inflammatory mediators (Interleukin-6 and C-reactive protein) revealed that both significantly (P < 0.001) increased in the formalin exposed group compared to EMA and control groups. These results confer that EMA could be a safer option to reduce health hazards of formalin in the workplace environment.

Role of steroid growth promoter on growth performance and meat quality traits in broiler.

Growth promoters are added with broiler feed to boost the overall feed efficiency and growth rate. The current study investigated the effect of dexamethasone (DEX)-a commonly used growth promoter-on the broiler growth rate, meat quality, and muscle biology. Four homogenous groups (20 chicks/group) of broiler one-day-old chicks were fed commercial broiler feed where the treatment groups received 3, 5, and 7 mg/kg of DEX with their diet for 28 d. Feed consumption and body weight were monitored on a daily basis. Muscle samples were collected on 7, 14, 21, and 28 d of the experiment to investigate meat quality and muscular biology. The residue of DEX in meat was detected using thin-layer chromatography. We observed that DEX had substantially decreased (P < 0.05) feed intake, feed efficiency, and overall weight gain in the broiler. While the weight of breast and thigh meat was decreased, the relative meat weight (meat/body weight) was increased significantly in chicks fed DEX. Simultaneously, body fat decreased while the percentage of fat increased significantly (P < 0.05) in the DEX groups. Contrariwise, DEX improved the investigated meat quality parameters with the potential threat of accumulation of DEX residue in the meat at a high dose (7 mg/kg). We also observed that DEX significantly increased the number of myofibers and decreased the cross-sectional area of myofibers. Based on these findings, we conclude that DEX reduces feed intake, feed efficiency, and growth rate, but might improve meat quality with a potential risk of residual DEX accumulation if fed at a high dose.

Alcoholic fixation over formalin fixation: A new, safer option for morphologic and molecular analysis of tissues.

Formalin is a widely used fixative but there is potential public health risks to exposure. Besides, alcoholic fixation is advantageous over formalin fixation because of faster fixation, optimal preservation and safer workplace environment. Following fixation by EMA and 10% neutral buffered formalin (NBF), we analyzed the tissue morphology, antigenic stability, DNA and RNA quantity with quality (OD value). The findings of EMA fixing on both the tissue morphology and molecular characterization, were satisfactory. Specially, EMA was faster in penetration of tissues than NBF, fixed ideally as early as 8 h of fixation whereas improper fixation was evident for NBF. In Hematoxylin and Eosin (H & E) staining, better cellular details with stronger affinity for staining were observed. In immunohistochemistry, better antigenic stability was reported for EMA-fixed tissues. The nucleic acid analysis revealed that total genomic DNA and RNA yield from EMA fixed tissues were significantly higher (P < 0.05) with superior quality than NBF fixed tissues. Our results suggest that EMA could be a potential alternative to NBF for fixation and preservation of tissues. These data provide new insights into an option for a safer working environment to support study and research.

Biochemical and morphological attributes of broiler kidney in response to dietary glucocorticoid, dexamethasone.

Glucocorticoids (GCs) initiate oxidative stress and cause renal damage which lead to hypertension, heart failure and ultimately death. The current study aimed to investigate the alterations in serum biochemical parameters i.e. HDL and LDL; gross anatomy, histomorphology and histomorphometry of broiler kidney in response to dietary GC, dexamethasone (DEX). Day old chicks (DOCs) were randomly assigned into four groups: control and three treatment groups (T1, T2 and T3). The control group was fed commercial broiler type ration and the treated groups were fed commercial broiler type ration containing GC (Dexamethasone @ 3, 5 and 7 mg/kg in T1, T2 and T3 group respectively). To measure the biochemical parameters, blood samples were collected on days 7, 14, 21, and 28 of the experiment. For histological investigation, kidney (left) samples were collected from the individual birds after sacrificing on days 7, 14, 21, and 28 of the experiment. Histomorphological alterations of the kidney were assessed by routine hematoxylin and eosin (H&E) staining. Biochemical analysis showed significantly increased serum HDL and LDL level compared to the control. In gross study, dark congested kidney was found with significantly decreased weight, length and width. Treatment with DEX augmented congestion, inflammation and fibrosis in kidney, as evidence by histomorphometric study. Extensively degenerated and atrophied glomeruli, degenerated tubular epithelium with distorted tubules and inter tubular empty spaces were seen. Percentage of atrophied glomeruli increased significantly and maximum percentage of glomerular atrophy was seen at day 28. These changes were found more explicitly in the higher dose group. Histomorphometric study also revealed significant decrease in the diameter of glomerulus. The findings of this study suggest that DEX may alter the serum biochemical parameters as well as kidney gross and histomorphology.

Histological architectures and biometric characteristics of indigenously plastinated organs of goat / Arquitectura histológica y características biométricas de órganos de cabra plastinados localmente

SUMMARY: The histo-morphology and biometry of liver, lung and kidney of goat were studied. The obtained samples were divided into two groups. One set of tissue was processed for paraffin embedding after formalin fixation. The other set was indigenously plastinated. The plastinates were embedded with paraffin without deplastination. Both the non plastinated and plastinated tissues were sectioned and processed for routine staining. The tissues were examined under light microscope for histological architectures and quantitatively assessed the biometric parameters. The non plastinated and plastinated samples yielded mostly similar histological architectures. But plastinated liver showed alterations and artifacts with enlargement of the central vein and hepatic sinusoidal space. Plastinated lung revealed enlarged alveolar sac. Lack of nuclear clarity was observed for all the plastinated samples. The plastinated kidney revealed compactness of the cellular structures and shrinkage induced artifacts with clear renal corpuscles structure and obvious glomerular capsule (Bowman's capsule). The biometric measurements of central vein of liver, alveolar sac of lung, glomerulus and glomerular space of kidney of both plastinated and non plastinated tissue were also performed using calibrated stage micrometer. Comparison was done between the biometric data for both plastinated and non plastinated tissue. No significant difference was found in the obtained biometric data of liver and lung. Only a significant difference was observed between the width of glomerulus of non plastinated kidney and width of glomerulus of plastinated kidney. The morphological and biometric study of non plastinated and plastinated organs of goat can conclude that histological slides can be made from indigenously plastinated organs with well preserved histological architectures of the tissues with some rare exceptions. Plastination does not affect the biometric characteristics of the organs. In addition, the comparative morphologic and biometric study of plastinated and non plastinated organs of goat will be useful in education and research.

RESUMEN: En este estudio se analizó la histomorfología y biometría de hígado, pulmón y riñón de cabra. Las muestras obtenidas se dividieron en dos grupos: una cohorte de tejido fue procesada para su inclusión en parafina después de la fijación con formalina. La siguiente cohorte fue plastinada localmente. Tanto los tejidos no plastinados como los plastinados fueron seccionados y procesados para tinción de rutina. Los tejidos se examinaron con un microscopio óptico en busca de arquitecturas histológicas y se evaluaron cuantitativamente los parámetros biométricos. Las muestras no plastinadas y plastinadas produjeron arquitecturas histológicas en su mayoría similares. El hígado plastinado mostró alteraciones y artefactos con un aumento de la vena central y del espacio sinusoidal hepático. El pulmón plastinado reveló aumento del saco alveolar. Se observó falta de claridad nuclear en todas las muestras plastinadas. El riñón plastinado reveló compacidad de las estructuras celulares y artefactos inducidos por contracción con estructura clara de corpúsculos renales y obvia cápsula glomerular (cápsula de Bowman). Las mediciones biométricas de la vena central del hígado, el saco alveolar del pulmón, el glomérulo y el espacio glomerular del riñón de tejido plastinado y no plastinado también se realizaron utilizando un micrómetro de platina calibrado. Se realizó una comparación entre los datos biométricos del tejido plastinado y no plastinado. No se encontraron diferencias significativas en los datos biométricos obtenidos de hígado y pulmón. Se observó una diferencia significativa entre el ancho del glomérulo del riñón no plastinado y el ancho del glomérulo del riñón plastinado. En el estudio morfológico y biométrico de órganos de cabra no plastinados y plastinados se puede concluir que es posible hacer portaobjetos histológicos a partir de órganos plastinados naturales con arquitecturas histológicas de los tejidos bien conservadas, con algunas excepciones. La plastinación no afecta las características biométricas de los órganos. Además, el estudio comparativo morfológico y biométrico de órganos plastinados y no plastinados de cabra será de utilidad en la educación y la investigación.

Post-natal macro- and microscopic changes of the thymus of Sonali chicken in Bangladesh.

OBJECTIVES: Avian lymphatic system plays a very significant role in immunity as well as disease control. This research aimed to investigate the histomorphological changes and involution of the thymus of Sonali chicken at different post-natal stages in Bangladesh as the age-related changes of the thymus of Sonali chicken were not described before. MATERIALS AND METHODS: A gross and microscopic investigation was performed on the thymus of 25 healthy Sonali chickens representing different stages of post-natal life: days 1, 14, 28, 42, and 56. Experimental chickens were sacrificed by cervical subluxation, and the thymus was collected and subjected for both the gross and histological studies. The histological changes were examined with light microscopy after H&E staining. RESULTS: The thymus was located in close association of the jugular vein, having a long chain of thymic lobes, 5-8 lobes on each side. The statistically significant age-related changes were observed (p < 0.05). All gross parameters (weight, length, width, and thickness) found to be increased up to day 42. On day 56, the growth was found to decline from the previous groups. The microscopic observations revealed the same pattern of changes such as gross parameters, i.e., continuously increased till day 42 and then declined (p < 0.05). At day 56, the involutory signs such as partial loss of interlobular septa and accumulation of adipose tissue in connective tissue septa were found. CONCLUSION: It is well known that in chicken, after a certain period, the thymus got involuted. In Sonali chicken of Bangladesh, the age of involution was notified at day 56/8th week of the post-natal stage, which was correlated both in macro- and microscopic observations.