dariush gharibi

Mycobacterium avium subspecies paratuberculosis is the cause of a common disease in dairy herds. Early diagnosis of paratuberculosis infection can improve Johne’s disease control programs.

This study aimed to compare the sensitivity, and specificity to methods; blood serum ELISA and stool Nested-PCR for the detection of Mycobacterium avium subspecies paratuberculosis infection in dairy cattle.

A commercial ELISA kit was used to perform the absorbed ELISA test, which was conducted after exposing serum samples to Mycobacterium phlei antigens to limit cross-reactions. Nested-PCR test was performed using nucleotide sequences related to specific MAP gene fragments, i.e. IS900.

As a result of the ELISA antibodies kit, out of the total 2203 serum samples, 112 samples were positive (5.08 %) and 2091 samples were negative (94.92 %). The results of Nested-PCR tests of rectal feces showed that out of 59 cows with the positive results in serum ELISA, 47 (79.66 %) samples were positive and 12 (20.34 %) samples were negative. Moreover, out of 31 cattle with a negative result on the ELISA test, 15 (48.38%) and 16 cattle (51.62 %) had positive and negative results, respectively, on the nested PCR tests of the feces samples.

Due to the low sensitivity of PCR compared to ELISA, the positive and negative predictive values, and the accuracy of ELISA test, as well as the high cost and time-consuming nature of PCR and the need for more and more complex facilities than ELISA, the authors concluded that ELISA is a more suitable method for screening and epidemiological studies than PCR.

There has been a growing concern about the potential transmission of Staphylococcus aureus strains among human and animal species through the consumption and handling of foods of animal origin.

The present study aimed to determine the source and possible route of milk and dairy contamination in Khuzestan province of Iran.

A total of 150 raw cow’s milk and 50 traditional cheese samples were collected from local markets in different cities of Khuzestan province, Iran. Presumptive colonies on Baird Parker Agar were subjected to the Polymerase Chain Reaction assay in order to identify the Staphylococcus genus, thermonuclease gene specific for S. aureus, enterotoxigenic gene (sea), and coa gene for coagulase gene. Moreover, biotyping of S. aureus strains was implemented based on Devriese’s system, and the antibiotic susceptibility testing (five antibiotics) was carried out.

Overall, 80 Staphylococcus spp. was isolated from the samples. The PCR was performed and, as the result, 23 S. aureus were confirmed, out of which 2 isolates (8.6%) belonged to the human ecovar and 17 isolates (73.9%) belonged to the non-host specific (NHS) biotype, whereas 4 isolates (17.3%) remained unclassified. Furthermore, sea gene and coagulase genes were detected in 3 and 22 isolates, respectively. The rates for contamination with S. aureus in milk and in cheese were 15% (19 samples) and 8% (4 samples), respectively. Overall, 4%, 9%, 17%, 35%, and 56% of isolates were found resistant to gentamicin, erythromycin, oxacillin, trimethoprim, and penicillin, respectively.

The local milk and cheese supplied in the given area were contaminated with antibiotic-resistant and enterotoxigenic staphylococci. Therefore, it was recommended that the supply chain of these materials should be carefully monitored in order to prevent the complications caused by the contamination with these ecovars.

Lactococcus garviea is a gram positive, facultative anaerobic, oxidase and catalase negative that belong to the lactic acid group bacteria. This bacterium is the cause of Lactococcosis, an acute disease with hemorrhagic septicemia in rainbow trout and causes a lot of economic damage to the aquaculture industry. In this study, 10 diseased rainbow trout were bacteriologically sampled from head kidney and brain in one of fish farms of Khuzestan province, Located in Masjed Soleyman. The obtained isolates were further evaluated by biochemical tests and molecular method (with 16S rRNA specific primers). Samples were also taken from different organs and fixed in formalin 10% for pathological examination. To investigate the lesions, sections were prepared from 5 μm and stained with Hematoxylin-Eosin. The results of bacterial culture, biochemical tests and PCR confirmed the presence of Lactococcosis in the studied farms. Macroscopic examination revealed lesions in the liver, kidneys and intestine of affected fish. The liver was pale and the kidneys were relatively swollen. No other complications or lesions, including abdominal discharge, were observed in affected fish. In histopathologic examination of liver, degeneration, and focal necrosis were seen. In kidneys, tubules degeneration and melanomacrophage cells accumulation were seen. In intestines, moderate inflammation and inflammatory cells aggregation was seen. According to the confirmation of the presence of lactococcosis, it is necessary to take measures to prevent lactococcosis (especially vaccination).

Crystalluria is one of the most important factors contributing to the pathogenesis of urinary stones. The type of the present crystal in urine can be associated with urinary tract infection and bacteriuria. The aim of the present survey was to evaluate the frequency of crystalluria and bacteriuria in companion dogs of Ahvaz district. For this purpose, the urine of 101 healthy dogs was obtained by catheterization. Physical assessment was initially carried out for specific gravity, color, clearance and apparent characteristics, and then the biochemical analysis was performed on the presence of hemoglobin, glucose, protein, ketone bodies and pH in urine. Urinary sediment was also evaluated for the presence of crystals, castes and cells. Urine specimens were investigated for the type of Staphylococcus, Proteus and Escherichia coli bacteria. Overall twenty cases (19.80%) had crystalluria; of these numbers, fifteen cases (75%) were struvite, two cases (10%) oxalate calcium dehydrate, two cases (10%) mixed of struvite and oxalate-calcium dehydrate and one case (5%) mixed of oxalate calcium dehydrate and bilirubin. From out of 101 samples, 40 cases (39.60%) had positive urine culture; of that number, sixteen cases (40%) were positive for Staphylococcus epidermidis and twelve (30%) for E. coli. Proteus was not isolated in any of samples. There was no significant relationship between gender and breed with bacteriuria and crystalluria (p>0.05), but a significant difference was observed for age; so that with age rising, crystalluria and bacteriuria were increased (p

Scorpions (order: Scorpiones) are widely distributed predatory arachnids and highly resistant to environmental conditions. Some factors such as microorganisms of internal cavity of scorpions may affect their biology. In addition, microbial communities of gut effect on immunity system and nutrition in arthropoda. However, few data are availablefor the microbiota diversity of scorpion gut. Thus, the present study aimed to evaluate the microbial diversity of scorpions related to the Buthidae family which is considered as the most important scorpions from south-west of Iran by chemical test and sequence analysis of 16S rRNA gene. To this aim, both gram positive and negative bacteria were detected from the gut of Androctonus crassicuda, Hottentota schach and Mesobuthus epeus. The staphylococcus saprophyticus, Bacillus cereus, Bacillus firmus, Corynebacterium variabilis, Pseudomonas putida, Pseudomonas oryzihabitans, Enterobacter aerogenes, Pantoe aagglomerans, Serrati aureilytica, staphylococcus gallinarum were isolated from the gut of scorpion. The isolated bacteria may have symbiotic or pathogenic relationships with scorpions. The present study was first considered the gut of buthide scorpion of Iran and can provide a reference for future studies on the digestive system microbiota from other scorpions by determining the role of these bacteria in the biology of scorpion.

Using of probiotics as organisms that can cause increasing the health and resistance to disease in host, can be reduced the use of antibiotics in aquaculture. In this study, isolation of lactic acid bacteria, Enterococcus sp. and Bacillus sp. from the intestine, water and sediment of the environment of Litopenaeus vannamei from Choebde region of Abadan, Khuzestan, done firstly and then the antimicrobial activity of isolated bacteria against Vibrio harveyi, Yersinia ruckeri, Aeromonas hydrophila and Lactococcus garvieae in two methods of agar well diffusion assay and Cross streak assay, were investigated. Based on the obtained results none of the Bacillus and Enterococcus isolates showed any antimicrobial activity against pathogenic bacteria with both methods but most isolates of acidic bacteria had antimicrobial activity. Afterward three isolates of bacteria with the highest antimicrobial activity (isolates 93, 94 and 95) were identified by sequencing of 16 S rRNA and all of three isolates were identified as strains of Lactobacillus plantarum after the sequencing.  Therefore, based on the results of this study, these isolates can be used for the purposes of probiotic in aquaculture, especially shrimp industry in the country, after invitro and invivo studies.

In recent years, use of probiotics has increased in aquaculture to improve the immunity and resistance to diseases in fish. In this study, two bacteria with probiotic ability, Lactobacillus pentosus and Lactobacillus plantarum, added to rainbow trout feeding during 60 days. Also a control group without administration of probiotic were selected. At the end of this period, the growth and digestive enzymes of fish were studied. After 60 days, the fish fed the diet containing probiotic show significantly improved specific growth ratio (SGR), protein efficiency rate (PER) and body weight gain (BWG) (p<0.05). The Food conversion ratio (FCR) was significantly higher in the control group than in the other two groups (p<0.05). At the end of this period, lipase, amylase and trypsin showed a significant increas in comparison to the control group (p<0.05), however alkaline phosphatase and protease had no significant differences as compared with control (p>0.05). It can be cocluded that the use of Lactobacillus pentosus and Lactobacillus plantarum distinctly affect on improvement of growth and digestive enzymes and they can be helpful in digestion of feeding ingredients in rainbow trout.

Caseous lymphadenitis, caused by Corynebacterium pseudotuberculosis, is one of the most important diseases of sheep and goats, causing considerable losses for herd owners. Phospholipase D (PLD) is a potent exotoxin produced by C. pseudotuberculosis and it has been considered as the major virulence factor for this bacterium, possibly contributing to the spread of the bacteria from the initial site of infection to secondary sites within the host. Heat shock proteins (HSPs) are important candidates for the development of vaccines because they are usually able to promote both humoral and cellular immune responses in mammals.
The aim of this study was the cloning and expression of the PLD and HSP60 genes of C. pseudotuberculosis, used subsequently to evaluate the protectivity of these recombinant proteins for vaccine development against this bacterium.
PLD and HSP60 genes were cloned into pMAL-c2X vector and recombinant plasmids construct was transformed to DH5 strain of E. coli. Expression of the proteins was shown by SDS-PAGE and accuracy of the cloned genes was confirmed by nucleotide sequence analysis.
The transformed E. coli strain DH5 expressed PLD and HSP60 proteins effectively. The expressed fusion protein was found almost entirely in the soluble form.
In the following studies the immunogenicity and protectivity of these recombinant proteins against C. pseudotuberculosis infections can be assessed.

Staphylococcal protein A (SPA) is a cell wall component of Staphylococcus aureus that binds to different IgG subclasses of human and several animal species. This bacterial protein can be used as an antibody detector in various immunological assays or as an isolation reagent for the purification of antibody molecules via immuno-chromatography procedures.
Molecular cloning and expression of SPA followed by the purification and conjugation of the recombinant protein to peroxidase enzyme.
Material and Encoding DNA fragment of SPA was amplified and inserted into a prokaryotic plasmid vector for the expression of recombinant SPA fused to a maltose binding protein (MBP). The recombinant protein was purified using amylose resin column chromatography and conjugated to horseradish peroxidase (HRP) enzyme. Finally, the reactivity of the recombinant SPA was examined against human IgG molecules in ELISA.
The results indicated that the recombinant peroxidase-conjugated SPA has a good recognition capacity for human IgG molecules and it was able to produce significant OD values after reacting with human IgG molecules at a concentration up to 0.06 mg.well-1.
This recombinant protein can be very useful in all research laboratories and may decrease some of the expenses, e.g. those for preparing conjugated anti-antibodies.