فصلنامه پاتوبیولوژی مقایسه ای
سال هفدهم شماره 67 (بهار 1399)

The morphology of the large intestine in birds is different. In addition to its nutritional role, because of the existence of lymphatic tissue, it plays an important immunological role. The present study was designed and conducted to expand the histological knowledge of the gastrointestinal tract in birds by evaluating the histomorphology of the cecum and colon at different ages. For this purpose, 36 ostrich chicks were selected in 6 age groups. These samples were selected from slaughterhouses around Tehran at the ages of one and fifteen days and one, three, six, and twelve months. In this study, it was found the epithelium of the cecum is pseudostratified and simple columnar, and the number of goblet cells increases with the age of the chickens. The muscularis mucosa at the base of the cecum was indistinct and thin, but clear at the apex of the cecum and colon. The thickness of the muscular layer increased with age the Auerbach plexus were mostly seen between the fibers of the longitudinal layer of the muscular layer. The lymphatic tissue was also observed in follicular shape in the lamina propria of the cecum from the age of six months. Based on the results, it can be concluded that in general, in terms of histomorphological features, the development of the large intestine in ostrich chickens is very similar to other birds, especially the Struthioniformes. However, the differences can be found in the condition of the muscularis mucosa and the distribution and timing of lymphatic tissue formation.

The sensitivity and specificity of milk somatic cell count (SCC) and bacterial culture as the golden standards for the diagnosis of bovine subclinical mastitis are low. Mastitis leads to the increased formation of free radicals, elevated oxidative and nitrosative stresses, and decreased antioxidant activity in milk. Therefore, the aim of this study was to determine the diagnostic value of milk malondialdehyde (MDA) and total antioxidant status (TAS) for the diagnosis of subclinical mastitis in dairy cows. A total of 90 clinically healthy Holstein cows were randomly selected from dairy farms of Tehran province, Iran. Next, 55 of these cows were diagnosed to have subclinical mastitis based on an SCC of higher than 130×1000 cells/mL of obtained milk samples. Milk MDA level was determined by the thiobarbituric acid method and TAS was measured using a commercial kit (Randox Laboratories, England). The diagnostic sensitivity, specificity, and cut-off points for the tests were determined by the receiver operating characteristic analysis. Our findings revealed that the mean and median of milk MDA and TAS were significantly higher and lower in the milk samples collected from cows with subclinical mastitis, compared to the healthy subjects. Moreover, milk MDA level was found to have the highest clinical accuracy at the cut-off points of 44.5nmol/ml. The results showed that the sensitivity and specificity of this biomarker in milk for subclinical mastitis diagnosis was both 100%. According to the results of this study, MDA can be considered as potential reliable substitutes for SCC in the diagnosis of bovine subclinical mastitis.

For this purpose, 360 Zebra fish were divided into two groups and fed for 60 days with commercial food (control group) or enriched diet with Lactobacillus fermentum as probiotic (test group). After this time, both groups were in the vicinity of 0.3 mg / l of lead and their survivability, tissue metal uptake and their histological damages were studied within 48 hours. Based on the results, the fish in the test group were able to tolerate the lethal dose of lead for more than 24 hours compared to the control group. After 48 hours of poisoning, the amount of metal uptake in both liver and gill tissue was significantly lower for the experimental group than in the control group. Moreover, tissue damage such as vein dilatation, lamella fusion and telangiectasia were significantly lower in the experimental group than the control group. Epithelial cell hyperplasia was not observed in the probiotic- treated group. It could be concluded that probiotic enriched diet can significantly reduce the toxic effects of lethal doses of lead in fish.

Despite extensive progress in the production of anti-cancer drugs, attention to some natural products, such as Melittin from honey bee venom, is growing. Some studies have shown that this product has anti-cancer properties. To evaluate the effects of Melittin on function breast cancer indicators in inbred Balb/c mice as well as its effects on liver and renal enzymes, 4T1 cell lines were purchased from Pasteur Institute and were cultured and the induction of breast cancer was performed in the breast area of ​​mice. The 20-day treatment period was performed in 9 groups (including 6,3,1mg/kg body weight of Melittin, doxorubicin, cisplatin, PBS, DMSO, healthy control, negative control). At the end of the course, animal blood samples were taken then liver and renal biomarkers were measured after serum isolation. From the induced tumor tissue sample, after fixation in formalin, the immunohistochemical tissue slide was prepared and studied for KI67 expression. Results showed that renal (BUN) and liver biochemical markers (AST, ALT as well as ALP) had no significant changes in melittin treated group at the dose of 6 mg/kg compared to control group. The results of histopathology showed a decrease in tumor cell invasion in Melittin therapeutic groups, which was more evident at a dose of 6 mg/kg. In immunohistochemistry, KI67 expression did not show a significant change in all groups. The results of this study show the beneficial effect of melittin in preventing the growth of tumor cells without injuring the liver and kidneys compared to other common drugs.

Peste des petits ruminants (PPR) is an economically important viral disease between sheep and goats that is endemic in Iran. This study was performed to Comparison of Serumic Concentration of Vitamin A and Beta-Carotene in the Serum Positive Against Peste des Petits Ruminant and Healthy Dams in sheep and goats in healthy animals in Khodabandeh area in summer of 2018.During this study, 200 samples were collected from Jugular veins of sheep (150) and goats (50) which were not vaccinated against PPR disease and after serum isolation the samples were analyzed using competitive ELISA kit (ID.vet French). Seroprevalence of PPR in sheepwas 108 cases (72%) and in goats was 36 cases (72%). Seropositive animals were placed in the sick group (144 animals) and Seronegative animals were placed in the healthy group (56 animals). Then Serum levels of Vitamin A and Beta-Carotene measured in all serum samples by hexane method. The mean and standard deviation of vitamin A and Beta-Carotene in serum was 27/6 ± 4/1 mg/dl and 19/5 ± 3/2 mg/dl in diseased group and 58/9 ± 3/2 mg/dl and 19/8 ± 2/1 mg/dl in healthy group, Respectively. Serum level of vitamin A was significantly different between healthy and diseased animals (p<0.05), but Beta-Carotene serum level was not significantly different. The final result is that given the low levels of vitamin A in animals infected with the disease, in areas where the disease is contagious, it can be administered injectable form to provide this vitamin and strengthen the immune system.

The current study was conducted to investigate the dietary effects of various amounts of Zataria multiflora seed powder on hematological, biochemical and immunological parameters in broiler and native chicken, in a random study using 4 treatments including 0 (control), 100, 200 and 300 mg/kg of Z. multiflora powder in diet for 42 days. At the end point, blood specimens were taken from wing vein and after the preparation of the serum samples, the following biochemical factors were measured using standard assay kits: total protein, albumin, globulin, triglyceride, cholesterol, high density lipoprotein and low density lipoprotein as well as hepatic enzymes activates including, aspartate aminotransferase, alanine transaminase and gamma-glutamyltransferase. The number of lymphocytes and heterophiles also were counted. Furthermore, immunoglobulin contents were measured in serum samples. The obtained results showed that the herbal supplement can significantly alter all of the aforementioned factors in both races compared to the control. In addition, racial differences of the parameters including cholesterol, triglyceride, LDL, lymphocytes, heterophiles, ALT activity and IgM were recorded in control groups. Conclusively, supplementation with Z. multiflora powder can improve hematological and biochemical parameters in both races. However, the immunoglobulin contents did not change remarkably and seems like the higher amounts of the herbal powder should be used to improve immunological responses.

Hirudin is a 65-66 amino acids polypeptide which is secreted as an anticoagulant compound from salivary glands of medical leech. This drug is a very potent inhibitor of thrombin and is so effective for arterial and venous thrombosis prevention. The aim of the present research was to clone and express of hirudin gene in CHO cell line as a eukaryotic host cell. In this experimental study, a 221 bp fragment of hirudin gene was cloned into pcDNA3.1(+) vector. The pcDNA3.1(+)-hirudin recombinant vector was transfected into CHO cells by lipofectamine 2000 reagent. The eukaryotic expression of hirudin was evaluated by RT-PCR method. The pcDNA3.1(+)-hirudin recombinant vector was confirmed by PCR and enzymatic double digestion. Our findings showed that the mammalian expression of hirudin was successful. As, a 221 bp fragment corresponded to hirudin mRNA was observed on agarose gel after RT-PCR. The pcDNA3.1(+)-hirudin recombinant vector was constructed in this research successfully. This new recombinant plasmid can express the hirudin mRNA in CHO cells. Therefore, the recombinant protein that produced from this research can be a recombinant vaccine that could be applied for future research. Additionally, this construct has the potential to be use as DNA vaccine in next experiments.