نشریه میکروبیولوژی دامپزشکی
سال دوازدهم شماره 2 (پیاپی 33، پاییز و زمستان 1395)

Over the last few years, Streptococcus has been one of the serious difficulties in the cold-water fish farms and caused massive economic losses. With respect to outbreak of Streptococcus disease, the survey was carried out in warm seasons using 150 rainbow trout fish with clinical symptoms of streptococcosis. The specimens were randomly collected from Palanghan cold-water fish farm complex located in Kurdistan province. Specimens for bacteria culture were obtained from kidney, liver, and spleen of fish and were cultured on culture media of TSA and BA. Bacterial culture was implemented at the temperature of 220°C for 3-5 days. Species of bacteria were determined following purification using biochemical and molecular tests.
The opacity resulted from the culture of specimens in Muller Hinton Broth's culture medium were compared with McFarland's tube 5% (the number of bacteria 108-109). Then, Muller Hinton Agar's medium was used for performing antibiogram. It was observed that Streptococcus iniae was sensitive to Enrofloxacine, Florfenicole, Doxycycline, Erythromycin, Oxytetracycline, Tetracycline, Lincomycin, Sulfamethoxazole / Trimethoprim, Kanamycin and Neomycin, and resistant to Bacitracin, Lincomycin, Flumequine and Sulfadiazine / Trimethoprim. Streptococcus agalactiae was resistant to Lincomycin and Bacitracin. Moreover, Streptococcus agalactiae was sensitive to Enrofloxacine, Doxycycline, Florfenicole, Lincomycin, Tetracycline, Oxytetracycline, Erythromycin, Kanamycin, Neomycin, Flumequine, Sulfadiazine / Trimethoprim and Sulfamethoxazole / Trimethoprim. Additionally, Lactococccus garvieae was resistant to Bacitracin, Sulfadiazine/Trimethoprim, Lincomycin and Neomycin, and sensitive to Erythromycin, Enrofloxacin, Florfenicole, Doxycycline, Tetracycline, Oxytetracycline, Trimethoprim, Flumequine, Kanamycin, Lincospectin and Sulfamethoxazole/Trimethoprim. The results indicated that the three isolated species of bacteria causing streptococcosis disease, which could create similar clinical signs in trout, were resistant to Bacitracin, Sulfadiazine/Trimethoprim and Lincomycin. In conclusion, in order to avoid growing bacterial resistance and to take the most effective decision in terms of antibiotic therapy, usage of antibiotics without antibiogram must be avoided.

The aims of this study were investigate the effects of Silybum marianum seed on the intestinal microflora and immune system of broilers. Current research was conducted in a completely randomized design with 4 treatments, 4 replicates and 20 chicks in every replicate. Treatments included: basal diet without adding Silybum marianum seed powder, basal diet with 0.2% seeds of Silybum marianum, basal diet containing 0.4% of Silybum marianum and basal diet containing 0.6% Silybum marianum seed powder. To evaluate the efficiency of the immune system by injection of sheep red blood cells as antigen, immune response with haemagglutination method were measured and weight of immune organs such as spleen and bursa of fabricius were measured too. Also at the ages of 21 and 42, two groups of bacteria, Escherichia coli and Lactobacillus were counted. Total immunoglobulin of treatments 0.2, 0.4 and 0.6%, were increased significantly compared to the control. IgY in receiving treatment 0.6% of Silybum marianum significantly increased in comparison with the control and 0.2 0% of Silybum marianum. IgM of all Silybum marianum treatments are also higher compared to the control. The results showed that the number of lactic acid bacteria in treatments 0.4 and 0.6% of Silybum marianum compared to the control at 21 days was significantly increased (P

The purpose of this study was to investigate effect of secondary infection with Ornithobacterium rhinotracheale (ORT) on pathogenesis of avain influenza virus subtype H9N2 in specific pathogen-free (SPF) chickens. Sixty, one-day-old SPF chicks were randomly divided into three groups. They were kept in separate positive pressure isolators. On 21st day of study, the chicks in group 1 was infected intraocularly with 1×106 EID50 of H9N2 and three days later intratracheally with 1× 1010 CFU of ORT, group 2 only inoculated with H9N2 AI virus, intraocularly. Control group was inoculated with PBS, intraocularly. The samples from various tissues were collected at 6, 8, 10, 12, 14 and 16 days post-inoculation (DPI). In first group chickens exhibited ruffled feathers, depression, respiratory signs, reduced appetite and 10% mortality. The most remarkable clinical signs appeared on day 5 PI. While in second group had minor clinical signs. The H9N2 virus was not detected from organs of group 1 with increasing antibody except lungs of died bird on days 5 PI. The ORT was detected in the trachea and lungs on days 6 and 8 PI. The bacteria was also found in the heart and liver on day 8 PI and in trachea of died birds on days 5 and 7 PI. The results showed that infected chickens with the H9N2 AI virus under secondary infection by ORT cause exacerbate virulence and lesions of H92.

Application of newly designed enzyme inhibitors against viral enzymes is one of the modern and effective approaches in viral diseases treatment. Such inhibitors, by inactivating vital enzymes and interrupting viral proliferation, prevent the spread of infection. In this context, the HIV-1 integrase is of special importance. So far, three inhibitors against integrase were designed, approved and used clinically named: Raltegravir, Elvitegravir, and Dolutegravir. In present work and in order to study the action mechanisms for these inhibitors we at first performed serial docking experiments to find the best binding sites for these inhibitors and to extract their complexes with integrase. Next we simulated these complexes for 10ns period at native conditions to study inhibitors-integrase interactions. Our results indicate that Dolutegravir in contrast to other inhibitors exert more prominent effects on integrase structure. This inhibitor also reduced protein flexibility especially in protein flexible loop (residues 140 to 152) the phenomenon that leeds to decreased affinity of integrase for viral DNA. Our findings confirmed that chemical structure of Dolutegravir seems to be a good candidate to constructing more effective analogous.

Saprolegniasis is an important aquatic fungal disease that causes severe damages at different growth stages of aquatic animals. The aim of this study was to measure the minimum inhibitory concentration (MIC) of alcoholic and aqueous extracts of Carum capticum and Mentha piperita on Saprolegnia parasitica. The antifungal activity of the aqueous, ethanolic and methanolic extracts of M. piperita and C. capticum on S. parasitica was tested using a mycelial radial growth technique and minimal inhibition concentration values were estimated according to the micro dilution method. The results of antifungal activity by mycelia radial growth technique showed that the ethanolic extract of M. piperita had a significant antifungal activity (MIC=10mg/ml) compared with the other extracts against S. parasitica. The growth potential in S. parasitica increased with increase in the concentration. Growth inhibition values of plant extracts on S. parasitica in broth micro dilution method were not significant (MFC ≥ 2048). Our study suggests that natural products derived from the examined medicinal plants have the potential to be used as antifungal in fish culture.

Snail transmitted diseases are very important group of parasitological diseases. Fresh water snails act as intermediate host for trematodal parasites. The role of these snails as intermediate host has got the importance from the view point of environmental safe systems and public health. Snails are from family Lymnaideae, order Basommatophora, subclass pulmonata and class Gastropoda. Lymnaea gedrosiana snail measures from 11 to 16 millimeter. The shell of L. gedrosiana is very similar to Lymnaea peregra. Lymnaea gedrosiana is very similar to L. auricularia from the point of anatomy. The most prevalent lymneae genus snail in Iran is L.gedrosiana and could be found in every place of Iran. Snails as the intermediate hosts of Schistosoma and Fasciola are very importants from the medical and veterinary viewpoints. It was decided to collect snail samples of Lymnaea genus in (Lorestan, Borojerd) district. Snail samples were transport to special laboratory (Department of Parasitology). At razi institute six hundreds Lymnaea samples were identified from Silakhor plateau and Shirvan village. L. gedrosiana comprises eighty percent of all collected samples, when 600 other samples were collected from other regions of this place and none of them was L. gedrsosiana, then the rate of L. gedrosiana in all parts was estimated to 40 percent. This study was the first case of L. gedrosiana from Boroujerd region.

The aim of this study was the isolation and identification of lactic acid utilizing bacteria and evaluation of their potential to control ruminal acidosis in vitro. Rumen fluid was collected from three Holstein cow and Isolation was performed using aspecific medium. Characterization of isolates was evaluated based on the shape and gram staining, indole production, catalase activity and fermentation of some sugars. Identification of isolates was done using the nucleotide sequencing. The results of sequencing showed that the isolates had the most similarity with Megasphaera elsdenii DSM20460. In the next step, effect of isolates on reduction of lactic acid and control of pH was examined. One gram of easily fermentable feed and 10 ml rumen fluid added to glass vials and inoculated with two doses of each isolate (5.0 and 1 ml) then, incubated for 6h. Gas production, pH and lactic acid for each sample were measured. Use of bacteria decreased lactic acid concentration and increased gas production and pH (p

In recent years, there has been an increasing interest in usage of portable lightweight and accurate instrument such as refractometer in dairy industry. This paper attempts to show that each one of mentioned instruments in various cut-points what will be their performance. Randomly, 80 cattle (primiparous and multiparous) selected and lactation number, calving ease score, volume of colostrum at first-milking were recorded and somatic cell count (SCC), total solid (TS), specific gravity, Brix% reading and immunologlobolin G concentration of colostrum sample measured. Thirtytwo percent of colostrum samples in the current study had IgG concentration of lower than 50 g/L. The results showed an acceptable correlation (R2=0.679) between Brix% reading and IgG concentration measured by enzyme linked immunoabsorbant assay (ELISA), also interaction of hydrometer method and digital Brix refractometer (%) had a strong and positive (R2=0.711) correlation. Performance of digital Brix refractometer for identifying low quality colostrum elevated at cut-point 24%, so that the sensivity and specificity of instrument in mentioned cut-point were 85.5% and 96%, respectively. The current results confirmed digital Brix refractometer is accurate and have a good correlation with IgG concentration of colostrum, and diagnostic characteristics test of device could be better if used of fixed colostrum volume for measurement, but in the colostrum samples with high SCC adequacy of this portable on-farm device falls down.

The aim of research note was to collect, record and writing one of local Expressions infectious diseases of ruminants of Iran, ticks and diseases by them. The methodology used in the research for the first time in Iran, was a field study done that was distributing a questionnaire to 31 province veterinary departments to ask studied geographical area, and date. The result of the study has indentified 101 local names of tick and diseases by them in 28 out of 31 provinces. Their range was between 1 – 8. On the other hand, any dialect was not mentioned in the questioner of Alborz, Qom and Zanjan province. used familiarizing the public and who are in the linguistic field and the technical aspect of the veterinary medicine applications

Wound infections caused by Candida albicans has grown substantially in recent years. Development of drug resistance led to the use of biological materials may be considered as an alternative solution. Studies show that Mentha piperita and Rosmarinus officinalis contains flavonoids and menthol and hence they has antibacterial properties. We used sixty male Wistar rats (weight 195-205 g). One square surgical wound with dimensions of 1/5×1/5 cm were performed on the back of each animal and immediately became infected whit 0.1 ml of 1/5×107 CFU Candida albicans suspension. Then the rats were divided into 4 groups (control, placebo and Menthe piperita 3% ointment and Rosmarinus officinalis 3% ointment) each with 15 rats and randomly distributed into 5 subgroups each whit 3 rats (sample groups on different days). Wound healing activity was performed by histological qualitative studies and yeast counts on the end of 4th, 8th, 12th, 16th and 20th days after surgery. Edema rate in treated groups in comparison with control and placebo groups significantly decreased (p

The aim of this study was to evaluate the anti-bacterial effect of 13 common and costly kinds of the standard antibiotics and the aqueous extracts of Berberis, Onions and Garlic on Clostridium perfrigenes isolates from cases of necrotic enteritis of breeding Turkeys. For this purpose, in addition to the Antibiogram tests using with those antibiotics on 40 isolates of Clostridium perfringens of breeding Turkeys with necrotic enteritis, as well as the susceptibility of isolates was tested in the presence of aqueous extracts of barberry, onions and garlic too. Results were confirmed that majority of isolates were sensitive to the antibiotics of Chloramphenicol, Vancomycin, Sulfamethoxazole亸ꙺ�ꚸ and aqueous extracts of Barberry and Onions; as well as were resistance to the antibiotics of Tetracycline, Penicilline, Neomycin sulfate and aqueous extracts of Garlic. In this regard, the most effective on tested isolates for the extracts of barberry and the lowest anti-clostridial impact was recorded related to the antibiotic of Tetracycline that statistically; with the effects of all tested antibiotics and extracts were showed significant difference (p

Pasteurella multocida is responsible for significant infections of a wide range of animal species and human. The organism causes a variety of diseases which include pneumonic pasteurellosis of ruminants, porcine progressive atrophic rhinitis (PAR) in pigs, fowl cholera and bovine haemorrhagic septicaemia (HS). The pathogenicity of P.multocida is associated with various virulence factors include outer membrane and porin proteins like ompH, adhesins (ptfA, fimA, hsf-1, pfhA, tadD) and dermonecrotoxin (toxA). The aim of this study was to identify the presence of these virulence genes among ovine P.multocida isolates. Thirty P.multocida isolates obtained from sheep pneumonia cases were identified by bacteriological and biochemical methods. All the isolates were confirmed as P. multocida by PM-PCR using species specific primers, KMT1. Molecular capsular typing (CAP-PCR) showed that all of the isolates belonged to type A. All of the isolates harboured FimA and OmpH genes. The majority (93.3%) of the isolates contained PtfA , Hsf-1 and (90%) for ToxA. The frequency of TadD and PfhA genes was the lowest (36.6%). Presence of virulence factors of P.multocida isolates showed genetically potential in pathogenesis of ovine pneumonia. Further studies for phenotypic determination of virulence factors with ethology of pneumonia are suggested. Overall, investigations of virulence factors help us to selection of suitable strain for an effective vaccine production.

In November 2011, from one Apodemus sylvaticus which captured by live trap in Razan plain, blood were collected. After blood smear slides were dried and fixed with methanol, subsequently in laboratory stained with Giemsa and investigated with 1000X magnification of optical microscope for blood parasites. Trypanosoma grosi was observed in A. sylvaticus blood smear. This is the first report of T . grosi in rodents of Iran.