فصلنامه دامپزشکی ایران
سال پانزدهم شماره 65 (زمستان 1398)

Vibrio harveyi is of the bacterial flora of omnivorous fish intestine that is considered as one of the main causes of the Asian seabass (Barramundi) fish vibriosis disease in many cage farms in the world. The purpose of this study was to investigate the role of this bacterium in the mortality of Asian seabass fish in southern regions of the Iran.  In this study, in 11 cases of Asian seabass mortality, a total of 110 Asian seabass fish (80 suspected vibriosis fishes and 30 healthy fish species) from southern provinces (Khuzestan, Bushehr and Hormozgan) were sampled and bacterial culture from the internal organs was done. Biochemical and molecular characteristics (with specific primers of genus and species) of isolates were investigated. Nine (81.81%) cases of vibrios (Vibriosp). Were diagnosed as causative of mortality.  The results showed that in fish with symptoms of vibriosis, 70.76% of the isolates were V. harveyi. Also, in the seasonal study, the prevalence of V.harveyi, the losses due to vibriosis and the highest prevalence of infection with this bacterium were observed in spring. The antimicrobial susceptibility test of 46 isolates of V. harveyi isolates was also investigated. The results of this study indicate the significant role of Vibrio harveyi in the mortality caused by vibriosis in Asian seabass fish farms in Iran. The results are important for prevention perspective (health management and vaccination) and the effective treatment of Vibriosis disease in Asian seabass fish, these results are important.

This study was conducted to evaluate the effects of onion extract on lipid profile, some blood factors and performance in Torki Qashqai suckling lambs. In this experiment, 18 Torki Qashqai suckling lambs of 30 days’ age were used in a completely randomized design, over a 60 days’ trial with three groups and 6 replicates. Treatments were included: 1) basal diet without onion extract+ sheep milk, 2) basement diet containing 150 mg/kg onion extract + sheep milk, 3) basement diet containing 250 mg/kg onion extract+ sheep milk. Lambs from each group weighted at 7-days intervals and measured feed intake at every day. Final data were analyzed by ANOVA procedure and SAS software and means compared in the 5% level by Duncan test. The results showed that there was a significant increase in feed intake and daily weight gain in 250 mg/kg group than150 mg/kg group and control group. There were no significant differences between groups for feed conversion ratio. The use of onion extract significantly decreased the amounts of plasma triglyceride, LDL, VLDL and glucose but increased the amounts of HDL. No significant differences were observed between groups of albumin, globulin, cholesterol, urea, uric acid, creatinine and total protein. The results showed that the addition of onion extract improved performance and also led to positive effects on lipid profile in suckling lambs.

Johne’s Disease (paratuberculosis) is granulomatous, progressive enteritis, which is untreatable, especially in domestic and wild ruminants caused by mycobacterium avium subsp. paratuberculosis. There is no accurate statistical information on the prevalence of Johne’s disease in buffaloes of different regions of the country. This study was performed to detect mycobacterium avium subsp. paratuberculosis with different diagnostic ELISA, PCR, Histopathology and their comparison. For this purpose, from December 2016 to October 2017, Among 97 slaughtered buffaloes, above two years of age with poor physical conditions were collected from blood samples, associated ileocecal lymph nodes, ileocecal valve and liver tissue were transferred to the laboratory. The serum level of infection (ELISA) was 4.1%, The molecular (PCR) test showed an infection rate of 32% in the intestin , 31% in the associated lymph node and 24.7% in the liver, Histopathology examination by Ziehl-Neelsen's specific staining, The prevalence of infections in the intestines are 7.2%, associated lymph nodes are 8.2% and 3.1% in the liver. The granulomatous lesions of the intestine were stained by hematoxylin-eosin (H&E) method in 11 buffaloes, only in 9 buffaloes their molecular test results were positive. Other histopathology findings of eosinophilic enteritis, Lymphocytic enteritis, granulomatous enteritis, mucu purulent enteritis were 37.9%, 29.3%, 19%, 13.8%, respectively. In the associated mesenteric lymph nodes, granulomatous lymphadenitis was 68.6%, purulent lymphadenitis were 25.7%, and in liver chronic hepatitis were 32.6%, chronic parasitic hepatitis 11.66%, perihepatitis 23.9%, cirrhosis 6.5%, and leiomyoma 25% have been observed. Due to the lack of observation of acid-fast bacilli in the present study, acid-fast granular debris (Paucibacillary) form of suspected Johneʼs disease can be found. At the same time, the increase of Ahvaz buffaloes contamination requires more serious attention to scientific and administrative references than the previous study.

Zinc, insulin, and leptin play an important role in energy metabolism. Zn increases appetite. Increased serum Zn concentration increases leptin and insulin concentrations. However, leptin and insulin decrease appetite. Regarding the importance of serum levels of metabolites associated with food intake, this study aimed to evaluate the effect of high levels of zinc supplementation and its effect on leptin and insulin and metabolic-related metabolites such as NEFA and BHBA. The diet of Holstein cows as a control group contains 75 and 150 mg/kg and second treatment 110 and 250 mg/kg Zn before and after parturition respectively. Diets were isocaloric and isonitrogenous and the only difference was the proportion of Zn. Blood samples collected via tail vein of 24 cows per treatment on days -25, -5, 7, and 21 relatives to parturition. Serum concentrations of Zn, leptin, insulin, glucose, NEFA, and BHBA were measured. High level of Zn in the diet increased the serum concentration of Zn, leptin, and insulin before and after parturition but the concentration of glucose was constant. NEFA concentration affected by Zn level and increased but BHBA decreased on the 7th day of postpartum. In all probability, increase in serum Zn concentration caused to increase leptin and insulin level, and increased insulin signaling pathway enhances ‘ob’ gene expression. Due to insulin resistance in the transition period and increased leptin level because of increase in Zn concentration in blood, serum concentration of NEFA increased. Reduction in BHBA concentration was due to increase in insulin concentration and a greater consumption of triglycerides in the liver. In conclusion, increased level of Zn in diet caused to increase its serum concentration and consequently increased leptin, insulin and NEFA concentration in serum before and after parturition.

This experiment was conducted to evaluate the effect of electron beam-irradiated barley on viscosity, microbial population, digestive enzyme activities, histomorphometrical structure of broiler chicks. Treatments were barley at levels of 25% and 50% (raw and irradiated at 40 kGy) and corn-soya bean meal diet (as control, without barley) that used with five dietary treatments, four replicates and 12 birds of each for 42 days in a completely randomized design. Increasing levels of barley to 50% (raw or irradiated) in the diet significantly increased ileal viscosity compared to the other treatments. Broilers fed 50% irradiated barley diet had significantly lower viscosity compared to the broilers fed 50% raw barley. The inclusion of barley in the diet resulted in significantly decreased ileal pH when compared with a control diet. However, radiation of barley had no significant effect on ileal pH of broilers. Caecal populations of Coliform, E. coli and total aerobic bacteria were not influenced by the experimental treatments. Also the caecal population of Lactobacillus was decreased in broilers fed on 50% raw barley compared to 25% irradiated barley and control diet. No significant differences were observed among dietary treatments on amylase and protease activities of the jejunal digesta and in pancreatic tissue. Broilers fed 50% barley (raw or irradiated) diet had significantly higher lipase activities in pancreatic tissue compared to the other treatments. The villus height, villus width, crypt depth, crypt width, the ratio of villus height to crypt depth, epithelial thickness, muscle thickness, number of goblet cells and a total wall thickness of the duodenum and jejunum were not affected by the experimental treatments. The results of this study showed that radiation significantly decreased viscosity at the level of 50% barley. However, radiation was no significant effect on pH, microbial population, enzyme activities, histomorphometry of duodenum and jejunum.

Selenium is an essential nutrient that play a very important role in the body and is an antioxidant.  The biological role of selenium is based on its effects on the structure of many selenoproteins. This experiment aimed to investigate the effect of nano-selenium nutritional supplementation on blood and semen glutathione peroxidase activity in Khuzestan Arabian rams. In this experiment, twelve Arabian rams with an average weight of 73±3 kg and two to four years old were used. Animals were divided into three groups; the control group (without nano-Selenium) and two experimental groups that received the 0.4 and 0.8 mg nano-selenium per kg dry matter, respectively. The results showed that selenium concentrations in blood and semen increased in treatment 0.4 compared to the control, which was significantly increased in the blood. Blood and semen selenium concentrations in group 0.8 were significantly higher than group 0.4 and control. The blood and semen glutathione peroxidase activity significantly increased in treatment 0.4 compared to control and in treatment 0.8 compared to the control and treatment 0.4. Finally, it was concluded that Nano-selenium supplementation increases the blood and semen glutathione peroxidase activity of Arabian rams and treatment 0.8 showed the best results.

This study aimed to investigate the gonadal tissue structure and sexual hormones in the yellowfin seabream (Acanthopagrus latus) and sole (Euryglossa orientalis) collected from the Mussa creek. For this purpose, about 1200 fish (10fish/species/station) were collected from five selected stations in Mussa creek including Petrochemical, Gafari, Majidieh, Ghazaleh and Zangi stations  and Genaveh Port station (as control). After the biometrical assay, bleeding was conducted from the fish caudal vine and blood samples were moved to heparinized microtubes and serum was separated after centrifuging. Also, tissue samples were taken from the ovary and fixed in formalin. Tissue samples passed through a routine histological process and the tissue sections were prepared and stained with H&E. later, histological sections were studied under light microscope and microphotographs were prepared using Dino lite with Dinocapture software. The steroid hormones including 17-βestradiol (E2) and testosterone (T) were measured using the radioimmuneassay (RIA) method and gonadotropin hormones (GTHI and GTHII) were also measured by IRMA method. The most follicles observed in the ovarian samples of both species from different stations were in previtellogenic stages including chromatin-nucleolus, prenucleolus and cortical alveoli follicles. Also an increase in the interstitial connective tissue and atretic follicles were recorded in the ovarian samples from some stations especially Petrochemical station. The results showed that the level of steroids (E2 and T) was lower in fish from the Petrochemical station than others, while GTHs reached the highest level in these fish. Generally, the most alterations in gonadal tissue structure in both fish species were recorded in the petrochemical station, probably due to waste waters released into the water in this station from various petrochemical and color alkali industries surrounded this station.

Varroa destructor (Acarina: Varroidae) is one of the most important pests of the honeybee, Apis mellifera (Hymenoptera: Apidae) throughout the world which is an economically important infestation of honeybee in Iran. The present study carried out to assess the effect of Ferula pseudalliacea (Apiaceae) extraction on the examined mites. The plant collected from the mountainous regions of Marivan suburb, Kurdistan Province, Iran and extracted by using Rotary evaporator. In an infested apiary, three infested hives (3 mites/ 20 honeybees) selected as treatment and control groups to determine the effect of F. pseudalliacea extraction (1.44mg/ml) on V. destructor. The dead mites removed from the litter of hives of all groups and counted at different times. There was a significant association between the effects of F. pseudalliacea extraction (34.40±9.652) and number of V. destructormites in control group (3.6±1.342). During the study, the highest effect of F. pseudalliacea extraction and Apistan on the number of V. destructor mortality was in 36(30.72%) and 24(39.91%) hours, respectively. There was a significant association between F. pseudalliacea extraction and Apistan groups. From the results of this study, it indicated that F. pseudalliacea extraction might play an important role in V. destructor infestation in honeybees.

The ruminants newborn is susceptible to neonatal infections due to the immature immune system. Antioxidants can enhance the function of the immune system cells. Levamisole is an antioxidant that has been proposed as an immune system stimulator in ruminants infant.The aim of this study was to determine the effect of adding levamisole powder to colostrum on plasma oxidant-antioxidant balance in newborn kids.This study was performed on 18 male and female mixed breed newborn kids (average weight 3 kg). The kids were divided into 3 equal groups. Each group received one of the three oral treatments Includes; 30 ml saline, 400 IU vitamin E and 7 mg/kg of levamisole powder, per each of the three colostrum meals during the first 24 hours of life. At 0, 60, 150, 300, 720, 1080 and 1440 minutes after starting treatment, the plasma samples were taken from the kids and the amount of total antioxidant and total oxidant capacity of the plasma and its oxidative stress index were determined. Treatment with vitamin E and levamisole compared to negative control treatment caused a significant increase of the oxidant-antioxidant balance of the plasma towards the antioxidant. This study showed that levamisole has an antioxidant effect in the plasma of newborn goat kids.

The aim of this study was to evaluate the effect of heat stress on milk production traits in Iranian Holsteins and estimate the genetic parameters of milk production trait under heat stress condition. To evaluate the effect of heat stress on the studied trait, the data set was included 587745 first lactation test day records of 70468 Holstein cows from 645 milk-recorded herds by the Animal Breeding Center of Iran. The weather information was obtained from a meteorological organization. The temperature humidity index (THI) in recorded days was calculated and used in the model.   Effect of impressive factors on milk production including herd, year, season of calving milking times, the month recording, and temperature humidity index was the investigated by GLM process in SAS software and significant effects included in analysis model. Random regression model carried out to estimate genetic parameters under heat stress conditions using BlupF90 software. The results of fixed effects analysis showed that all survived factors had a significant effect on the milk production trait. The threshold point for THI was 72, and then by increasing THI up from 72, milk production decrease. This reduction is   -0.056 for increasing each unit in THI. The range of heritability for milk production trait estimated 0.1 - 0.22 and the correlation between THI and milk production was in the range 0.1- 0.9. The highest heritability related to the period that animal was in end of lactation and the THI was the lowest.

Heat shock protein 70 (Hsp70) is a chaperone that is expressed in response to stress. The purpose of this study was to determine sequences and single nucleotide promotor mutations and heat shock gene 70 and to investigate the effect of single nucleotide mutations on the three-dimensional structure and thermal shock protein function of Khuzestan native chicken strain using bioinformatics methods. To do this research, 20 native blood samples were taken from different locations of Khuzestan province. After DNA extraction, using several primers, promoter and heat shock protein 70 gene were amplified and sequenced. Three mutations were observed throughout the complete heat shock protein 70 gene. The first mutation in nucleotide position 259 (A259G) was observed, which guanine replaced adenine. The second mutation occurred at the nucleotide position of 277 (C277G), where guanine was replaced by cytosine. The third mutation occurred at the nucleotide position of 1749 (C1749G), where guanine was replaced by cytosine. In the first and second mutations, there is no change in the amino acid, but the mutation at position 1749 causes the serum amino acid to become tryptophan. The mutation occurred at the position of 583 amino acid heat shock protein but did not change the 3D building and its performance. This amino acid change causes more stability in the heat shock protein 70 and maybe one of the reasons for the resistance of the native to the heat.

RasGRP3 is one of the genes which are probably effective in the outcome of influenza infection. This gene reduces the inflammatory response and sets a threshold to decrease intensive response which usually causes harm to host tissues. In order to evaluate the role of this gene in the host response to Influenza infection, we analyzed transcriptomic data available in data banks and then performed Real-time PCR. We used 3 transcriptomic experiments to study the gene expression changes through infection compared to control groups. Then, we performed Real-time PCR on H5N1 infected samples. Transcriptomic data analysis using R software and MetaDE package via Fisher statistical method confirmed the differential expression of RasGRP3 significantly. Real-time PCR results indicated that RasGRP3 was down regulated in response to H5N1, significantly. The results show that RasGRP3 is one of the strong candidate genes in host regulatory mechanisms against Influenza infection which can set the intensity of host response through regulating the defensive system and can also affect the outcome of infection and survival.