فصلنامه آسیب شناسی درمانگاهی دامپزشکی
سال دوازدهم شماره 4 (پیاپی 48، زمستان 1397)

Recently, the use of medicinal plantsas growth promoters, appetizers, immunological boosters and antimicrobial substances has increased in poultry industry. In this regard, the effect of Zataria multifloraand Mentha pulegium on growth characteristics, carcass quality and gut microbial count of broiler chickens were investigated. This research was carried out in a completely randomized design with 120 broiler chickens of Ross strain in 4 different feed treatment groups and 3 replicates consisting of 10 chickens each. The treatment groups consisted of T1 (Control) fed with basic diet (without plants), T2 fed with basic diet containing 200 mg/kg of dried Mentha pulegium, T3 fed with diet containing 200 mg/kg of dried Zataria multiflora and T4 fed with diet containing a mixture of 200 mg/kg dried Zataria multiflora and 200 mg/kg dried Mentha pulegium for 6 weeks. All chickens were weighed weekly and at the end of the experimental period, growth characteristics including carcass weight, thigh weight and breast weight and intestinal microbial total count were measured in each group. The results were evaluated by one-way ANOVA and Duncan’s post-hoc test in SPSS 19. The results showed that the mean weight, the weight of thighs and breasts between treatment groups were not statistically significant but the intestinal bacterial count was decreased by these supplements (p<0.05). The maximum microbial load was observed in the control group (T1). Therefore, it can be concluded that the use of these supplements in chicken feed reduces intestinal microbial counttherefore organic and safe meat production can be expected.

Selenium has an important role in the metabolism of thyroid hormones because it is necessary in the conversion ofthyroxine (T4) to its active form triiodothyronine (T3). For this conversion, selenoenzymes which are mainly located in the liver and kidneys are necessary. This study was conducted to determine the effects of organic and inorganic selenium (Se) supplementation on serumic levels of thyroid hormones in mixed breed horses. For this purpose, 10 healthy mixed breed horses 4-5 years of age were randomly divided into two equal groups. The first treatment group received routine diet plus premix (1 mg sodium selenite/day) for 12 days and the second group was supplemented similarly with 1 mg commercially available yeast enriched organic selenium (O-Sel). Blood samples were taken by venoject tubes from the jugular vein on days 0, 3, 6 and 12. Serumic selenium concentrations were measured using atomic absorption and serum thyroid hormones were measured by spectrophotometer. After selenium supplementation, mean serum T3 levels increased significantly in both treatment groups (p<0.05) while T4 concentrations decreased. According to the results, administration of limited amounts of selenium can increase the active form of thyroid hormones with a positive impact on the performance of the horse.

In recent years, cold plasma in atmospheric pressure is used as a promising new therapeutic strategy in medicine for cessation of bleeding and skin wound healing. The aim of the present study was to evaluate the histopathological effect of cold argon plasma in atmospheric pressure on full-thickness cutaneous wound healing and increasing the speed of blood coagulation in rats. Forty-eight mature male rats were divided into two control and treatment groups. Under anesthesia, a 15 mm diameter skin wound was created on the back of the rats and blood coagulation time was measured. In treatment group immediately after the injury, the skin of rats was radiated by plasma once for 30 seconds and simultaneously blood coagulation time was measured. Then, control and treatment group rats were euthanized by ether at 0, 7 and 21 days after the injury respectively. The wound and surrounding healthy skin were removed and after hematoxylin-eosine staining, histopathological examination with light microscope was performed. Plasma radiation increased the speed of blood coagulation in skin wounds under in vivo conditions. Based on histopathological results, the process of full thickness cutaneous wound healing was significantly (p<0.05) better in plasma treated rats. Therefore, cold argon plasma can be used to increase the speed of blood coagulation and improve cutaneous wound healing.

Currently, global use of prebiotic compounds has increased considerably. This study aims to analyse the effect of complementing the rations of rainbow trout with different concentrations of Celmanax® prebiotic, which contains Saccharomyces cerevisia associated compounds with Mannan-oligosaccharide on gill and liver histology during the growing period and experimental challenge with yersiniosis. Four concentration levels of prebiotic (0, 0.1, 0.5 and 1%) were mixed into fish feed pellets. The fish (with mean body weight of 19.08±1.45 gr) were fed a supplemented commercial diet for 60-days.On day 60 of the study, experimental yersiniosis was induced in all treatment groups by intraperitoneal injection of bacterial suspension. Tissue samples were taken on days 0, 30 and 60 and also after induction of experimental yersiniosis. The results showed that complementing rainbow trout rations with different concentrations of Celmanax® improved the gill and liver injuries on days 30 and 60 of the study. The best tissue effects in the growing period were observed in treatment groups which received 0.1% and 0.5% of the prebiotic respectively, and after experimental challenge with yersiniosis, the lowest lesions of liver and gill pathology were seen in the treatment group fed with 0.1% prebiotic which was significantly different (p<0.05) from all other treatments. According to the results of this study, adding Celmanax® to rainbow trout diet at 0.1% concentration improves tissue parameters during breeding period and decreases tissue lesions when faced with yersiniosis.

Tissue fixation is a vital step in preparation of samples for histological studies and mistakes at this stage could lead to irreversible damage. The aim of this study was to compare the effect of three sample preparation-fixation methods on histomorphometic indices of small intestine of broilers. Thirty 10 day old broilers of Ross 308 strain were used in the study. Segments of small intestine were washed and prepared as opened or closed sections. The closed sections were fixed in 10% saline-formalin. The opened samples were cut at the mesenteric line and were fixed by 10% saline-formalin. In Clarke’s fixation the ends of samples were sealed by string and Clarke’s solution was injected into the lumen. Fixed samples were subjected to paraffin embedding and 5 µm sections were cut using rotary microtome and sections were stained by Eosin-Hematoxylin and Alcian blue. In each section the villus height, villus thickness, crypt depth and goblets’ density were measured under light microscope and the villus surface index was also calculated. Data were subjected to ANOVA in a completely randomized design with three treatments and 30 observations. The results indicated that method of preparation-fixation had a significant effect on morphometric indices (p<0.01). The closed-formalin’s samples had the greatest villus height and crypt depth values in all three intestinal segments, while the lowest values were observed in closed-Clarke’s method (p<0.01). Closed-Clarke’s samples had the thickest villus in all three parts of small intestine followed by closed-formalin’s and opened-formalin’s samples (p<0.01). Villus surface area was highest in closed-formalin fixed samples (p<0.01). Considering simplicity of the method, low cost, better mucosal protection and lack of severe tissue changes observed in closed-formalin’s method, this method was considered as a method of choice in histomorphometric studies of poultry small intestinal mucosa.

Nowadays, one of the main problems of human societies is the use of narcotics such as crack. The aim of this study was to investigate the effect of a single dose of crack on neutrophil phagocytosis in rats. For this purpose, 30 male Wistar rats were randomly allocated into 5 groups of 6 rats and kept in glass aquariums with 12 hours of light and darkness, same feeding conditions and free access to water. After acclimitisation to the new environment, intraperitoneal crack was injected with a dose of 7.8 mg/kg in four treatment groups. Under ether anesthesia, blood samples were collected from the tail vein after 3, 6, 24 hours and a week after crack injection in the treatment groups respectively and on the first day of the study in the control group. The strength of neutrophil phagocytosis was estimated after adjacency with yeast. A significant decrease in white blood cells was observed 3 and 6 hours after crack injection while significant decrease of neutrophils and increase of lymphocytes was seen 3, 6 and 24 hours following crack injection (p<0/05).The strength of neutrophil phagocytosis was also significantly decreased after three and six hours of injection (p<0/05) which could be attributed to the effects of crack on tissue migration of neutrophils, decreased life span of neutrophils or increased production of free radicals. Therefore, the use of crack can pave the way for creationof infection by decreasingthe number of white blood cells and strength of neutrophil phagocytosis.

Left displacement of the abomasum (LDA) is one of the most important production disorders. In order to compare the status of some hematological and serum biochemical indices, trace elements and oxidative stress of cows with and without LDA, blood samples were taken from 30 dairy cows with LDA and 30 healthy cows in early lactation period. Haematological parameters, total protein, fibrinogen, Ca, Mg, bilirubin, uric acid, albumin, cholesterol, triglyceride, urea, creatinine and AST (Aspartate aminotransferase), ALP (Alkaline phosphatase), GGT (Gamma- glutamyl transferase), CPK (Creatine phosphokinase) enzymes, Fe, Zn, Cu, Se, MDA and total antioxidant status were measured. Although the results showed significant differences in PCV, RBC, MCHC, lymphocyte, monocyte, fibrinogen, bilirubin, albumin, cholesterol, calcium, uric acid, AST and ALP enzymes between the two groups (p<0.05), but the occurrence of oxidative stress and changes in the levels of trace elements were not significant between the LDA affected and healthy cows. In LDA affected cattle, significant increase of PCV might be due to dehydration while increasing of monocyte and decreasing of lymphocyte counts could also be due to stressful condition or probable infections in early lactation. Anorexia, food deprivation and withdrawal of calcium from milk in early lactation may play a role in decreasing of albumin, cholesterol and calcium. Liver lipidosis and fasting along with biliary duct obstruction may be effective on increasing AST activity and bilirubin respectively in cows with LDA. It seems that early diagnosis and treatment of LDA can prevent the occurrence of sever changes in oxidative stress status and homeostasis of cow’s body.

This study aims to examine serumic indices of renal function in horses suffering from piroplasmosis and to compare them with healthy animals. Based on clinical signs and laboratory findings, 17 horses (14 males and 3 females) were diagnosed with piroplasmosis in horse ranches of the suburb of Tabriz city. After taking the history of these animals, blood sample was taken from the jugular vein and serum was separated. Also, 16 healthy horses (13 males and 3 females) were sampled as a healthy group with the same age, feeding and managerial conditions. Renal function was evaluated based on serumic level of blood urea nitrogen (BUN), creatinine (Cr), total protein (Pr), albumin (Alb), sodium (Na) and potassium (K). Mean serumic level of total protein and albumin had an insignificant increase in horses suffering from piroplasmosis, but increment of mean serumic level of creatinine and BUN was significant in the diseased group (p=0.000 and p=0.001, respectively). Serum variations of sodium and potassium were not significant between the two groups. The difference between mean serum parameters in diseased group was significant between the two sexes only in respect to total protein and albumin (p=0.001 and p=0.012, respectively). In healthy group, age did not have any effect on serum variations of measured parameters, but in the diseased group, mean serum total protein increased with increase in age (p=0.033). The results of this study indicated that renal function is affected in horses suffering from piroplasmosis and improvement of renal function using fluid therapy should be considered in the treatment of this disease.