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Ornithobacterium rhinotracheal (ORT) is a Gram-negative pathogen that is one of the causes of respiratory diseases in birds. Co-infection of Ornithobacterium rhinotracheal with other pathogens can cause serious health problems in bird species and also lead to financial losses in the poultry industry. Serological methods are among the most important techniques for rapid infection diagnosis, farm monitoring, infection control and prevention. The purpose of this study was to design an ELISA test to assess the prevalence of ORT and track the amount of ORT-specific antibody in serum collected from turkeys. After immunizing three pieces of turkey and obtaining the immunization serum, antibody purification was performed using ion exchange chromatography and affinity chromatography methods. The purified antibodies were then used in a homemade ELISA reaction as a standard sample to determine the quantity of specific antibodies against ORT. A total of 244 serum samples were collected from turkeys slaughtered in the poultry slaughterhouse of Khuzestan province. ELISA testing revealed the significant presence of antibodies against ORT in 141 (57.78%) of the samples. The average concentration of antibodies in positive samples was 467.72 ± 124.128 micrograms per milliliter of serum, while in negative samples it was 262.97 ± 37.263 micrograms per milliliter. This study revealed the prevalence of ORT infections in Khuzestan province. Therefore, due to the lack of a reliable vaccine against O. rhinotracheal, it is necessary to implement good disease management and biosecurity measures in order to effectively control the disease. [ABSTRACT FROM AUTHOR]

Background: Companion animals, including dogs and cats, are frequently identified as sources of Pasteurella multocida, a bacterium that can be transmitted to humans and cause infections. Objectives: This survey defines the prevalence, antibiotic sensitivity, capsular types, lipopolysaccharide (LPS) types and virulence factors of P. multocida isolated from cats. Methods: A total of 100 specimens from various cat breeds were collected. P. multocida was characterized using both biochemical tests and PCR. Genotypes of isolates were determined using capsular and LPS typing methods. Additionally, virulotyping was performed by detecting the presence of 12 virulence‐associated genes. Disk diffusion was used to determine the antibiotic sensitivity of the isolates. Results: The prevalence of P. multocida in cats was 29%. Among the isolates, the majority were capsular type A (96.5%) and type D (3.4%), with a predominant presence of type A. Twenty‐six of the isolates (89.66%) belonged to LPS genotype L6, whereas three isolates (10.3%) belonged to genotype L3. Among the 12 virulence genes examined, sodC, oma87, ptfA, nanB and ompH showed remarkable prevalence (100%). The toxA gene was detected in four isolates (13.8%). Variations were observed in other virulence genes. The nanH gene was present in 93.1% of the isolates, whereas the pfhA gene was detected in 58.6% of the isolates. The exbD‐tonB, hgbB, sodA and hgbA genes showed prevalence rates of 96.5%, 96.5%, 96.5% and 82.8%, respectively. Additionally, particular capsule and LPS types were associated with specific virulence genes. Specifically, the toxA and pfhA genes were found to be more prevalent in isolates with capsular type A and LPS genotype L6. Most isolates were resistant to ampicillin, clindamycin, lincomycin, streptomycin and penicillin. Conclusions: According to this epidemiological and molecular data, P. multocida from cats possess several virulence‐associated genes and are resistant to antimicrobial medicines commonly used in humans and animals. Thus, it is crucial to consider the public health concerns of P. multocida in humans. [ABSTRACT FROM AUTHOR]

Domestic poultry are considered natural reservoirs for the transmission of Campylobacter spp., mainly C. jejuni and C. coli, to other birds and humans. This study aimed to determine the Campylobacter infection status in backyard ducks in Iran. A total of 100 cloacal swabs were obtained from apparently healthy backyard ducks in different rural areas of Amol, a city in northern Iran. Bacterial isolation was based on traditional culture procedures, and genus and species identification were performed using an mPCR. All isolates were examined for antimicrobial resistance to seven antibiotics by Kirby Bauer’s disk diffusion test. The virulence-associated genes cadF, iamA, pldA, cdtA, cdtB, cdtC, and wlaN were detected as well. Out of the 27 Campylobacter isolates recovered, 19 (70.4%) were C. coli, and 3 (11.1%) were C. jejuni. The remaining five isolates (18.5%) were not identified. All (100%) isolates showed resistance to ciprofloxacin. Most isolates were resistant to ampicillin, tetracycline, and nalidixic acid. The resistance rate to amoxicillin-clavulanic acid and erythromycin was moderate but was relatively low to gentamicin. Moreover, over two-thirds of the isolates were MDR. All virulence genes, except iamA, were variably detected. The cadF and pldA genes had the highest (92.6%) and lowest (7.4%) positivity rates, respectively. In addition, a statistically significant association was observed between Campylobacter spp. and most of the critical virulence genes (p < 0.05). Our findings imply that backyard ducks should be paid attention to as a major source of human campylobacteriosis. [ABSTRACT FROM AUTHOR]

Enterococci are a part of the opportunistic pathogens, which are very important in medicine. These bacteria can cause a variety of diseases in both dogs and human. The aim of the present study was to investigate the frequency detection of Enterococcus faecalis and Enterococcus faecium in companion dogs in Ahvaz and review of risk factors including age, gender, breed and diarrheic status in animals. Also, the prevalence of virulence genes was evaluated including gelatinase (gelE) and (ccf) and antibiotic susceptibility measured in obtained samples. Sampling was performed from the rectum of the 150 dogs (36 cases diarrheic and 114 non-diarrheic). The samples were evaluated by two methods of bacterial culture and PCR. In bacterial culture, 122 isolates, suspected to Enterococcus species, were isolated and subsequently the detection of SodA gene specific to Enterococcus faecalis and Enterococcus faecium was performed by PCR. Overall forty-five positive isolates were identified, which thirty four of which were Enterococcus faecalis (75.5%) and 11 were Enterococcus faecium (24.5 %). In regard to identify virulence genes (gelE and ccf), 36 out of 45 isolates were positive for virulence genes. Twenty six isolates (57.77%) had virulence genes, 5 isolates (11.11%) ccf gene and 5 other isolates (11.11%) gelE gene. In all, nine isolates (20%) had no virulence gene. Fourteen different antibiotics were used to determine antibiotic susceptibility that indicated all isolates were resistant to azithromycin, streptomycin, ampicillin and imipenem. Thereafter, the highest resistance was related to erythromycin and cephalexin (95.5%), trimethoprim sulfamethoxazole (84.4%) and gentamicin (80%), respectively. Also, the highest sensitivity was related to nitrofurantoin (62.2%), penicillin G (60%) and enrofloxacin (55.5%), respectively. There was no significant relationship between risk factors such as age, gender, breed and diarrheic condition with the presence of Enterococcus in the studied dogs (P>0.05). The results showed that the prevalence of Enterococci was relatively significant (30%) in dogs of Ahvaz district. Antibiotic resistance was significant in the two species of Enterococci. Finally, because of the very high importance of antibiotic resistance, appropriate administration of antibiotics is recommended. [ABSTRACT FROM AUTHOR]

Background: It is known that ruminal acidosis can induce harmal population shifts in some ruminal bacteria profiles. However, there is little information related to alterations in faecal and ruminal bacterial communities and relevant serum lipopolysaccharide (LPS) in sheep with subacute ruminal acidosis (SARA). Objectives: This study aimed to investigate alterations in the defined faecal and ruminal bacteria profiles and serum LPS and blood lactate concentrations in lambs with empirically induced SARA. Methods: Fifteen lambs were served and undergone to induce SARA during a 7‐day period. Faecal and ruminal samples were taken to measure the pH and to perform the bacteriological works at 0 (just before induction), 8, 9, and 10 days of the challenge. Blood samples were collected to determine the serum LPS and lactate levels. The rumen and faecal samples were cultured to specify colony‐forming units (CFU) for Escherichia coli, Streptococcus Group D (SGD), and lactic acid bacteria (LAB). Results: Serum LPS value had no significant increase in the affected lambs with SARA. Significant increasing trends were observed in faecal E. coli and LAB populations (p < 0.01). Rumen bacteriology revealed a rising trend for LAB and a falling trend for SGD populations (p < 0.01). Conclusion: : Unlike cattle, LPS appears to be of minor importance in the pathogenesis of SARA in sheep. The increased ruminal and faecal LAB (4.00 × 107 CFU/ml or g) are proposed as valuable biomarkers for improving nutritional strategy and screening SARA in lambs. [ABSTRACT FROM AUTHOR]

Mycoplasmosis is one of the most important diseases in the poultry industry. mycoplasma synoviae is one of the important disease-causing factors in chickens, which causes respiratory tract infection and synovitis. and leads to significant economic losses to the poultry industry all over the world. In this study, mycoplasma infection of broiler flocks in Ahvaz slaughterhouse was investigated using molecular method. For this purpose, 200 samples of lung and trachea tissues and joint fluid of hock joint were collected from 20 broiler flocks with macroscopic symptoms and 20 samples from the mentioned parts from apparently healthy broiler chickens of each flock in the winter season. Tissue DNA extraction was performed. The polymerase chain reaction (PCR) was performed to detect Vlha gene of mycoplasma synoviae. Of the 200 samples, 55 lungs and 45 tracheas from flocks with macroscopic symptoms and 4 lung and trachea samples from apparently healthy birds were positive. In the molecular examination of joint samples, no positive cases were observed for the presence of mycoplasma synoviae. The PCR products of positive samples were sent to Gene FanAvaran Company for sequencing. The sequence of a part of the Vlha gene of this isolate was compared with other isolates in the gene bank and it was about 99% similar to the previous Iranian isolates (IRG11/C/09, IRG6/C/08, IRG1/C/08). According to the results of the present study, mycoplasma synoviae is common among broiler flocks under investigation in Ahvaz slaughterhouse. Therefore, the policy makers of the health system of the poultry industry should prevent the economic losses caused by this disease with preventive measures. [ABSTRACT FROM AUTHOR]

Allergic contact dermatitis is an inflammatory skin reaction caused by direct contact with an offending substance. The aim of this study was to establish a suitable method for induction of allergic contact dermatitis in dogs for future studies. For this purpose, 1%and 2% dinitrochlorobenzene (DNCB) were injected with and without ethanol and olive oil or acetone and olive oil subcutaneously in the back of 8 BALB/c mice (4 equal groups). Then, based on the types and severity of the symptoms, it was decided to sensitize the dogs with only 2% DNCB. Finally, in two stages, 2% DNCB with or without dimethyl sulfoxide (DMSO) was injected with ethanol or acetone and olive oil subcutaneously in thoracic and scapular regions of five dogs. Two percent DNCB challenge caused clinical findings including erythema, edema and skin scaling, as well as pruritus and scratching behavior in the mice. Clinical findings in dogs developed in mild severity including redness and swelling within a few days. There was a significant increase in total blood leukocytes, neutrophils, lymphocytes, eosinophils and monocytes counts at seven days in dogs. Also statistical analysis showed that one week after DNCB injection, IgE expression increased significantly and this increase continued until day twenty-one. Based on the result of this study, intradermal injection of 100 μL of 2% DNCB mixture with DMSO (dissolved in a 4:1 mixture of ethanol and olive oil) was a suitable method for induction of allergic contact dermatitis in dogs. Furthermore, the scapular region was also a convenient location to prevent self-induced lesions. [ABSTRACT FROM AUTHOR]

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Background and Objectives: Staphylococcus aureus is one of the major causes of bovine mastitis, which can be transmitted from animals to humans. Methicillin-resistant S. aureus (MRSA) isolates are more attentive and if not treated promptly, they can cause death. The aim of this study was to determine the prevalence of methicillin resistance and frequency of selected virulence factors of S. aureus isolates with bovine mastitis milk origin in Ahvaz, southwest of Iran. Materials and Methods: During a two-year period (2014-2015), 75 S. aureus isolates were recovered from referred clinical and sub-clinical bovine mastitis milk samples. The isolates were phenotypically investigated for resistance to cefoxitin by Kirby-Bauer method. DNA were analyzed by PCR for mecA and selected genes that encode the virulence factors. Results: According to the results, the spa, ebpS, fnb, bbp, clfA, clfB, and cna genes were detected in 98.7, 97.3, 97.3, 86.7, 84, 84 and 65.3% of the isolates, respectively. Among the 75 isolates, only one (1.3%) isolate was methicillin-resistant. Totally, 39 isolates (50.7%) had all of these virulence factors except mecA. The results showed that 96% of the isolates had at least the fnb, ebpS and spa genes, signifying the noteworthy role of these genes in the pathogenesis of S. aureus bovine intra-mammary infection in this area. Conclusion: In the present study, the prevalence of mecA was relatively low, possibly indicating that cows do not play a significant role in community-acquired MRSA infection in this area. According to the results, studied virulence factors were somewhat prevalent, bearing in mind the probable risk of transmission of these isolates from cows to humans, especially those that are in close contact with infected cattle. The data presented here can be used for the introduction of a protective vaccine against this infection. [ABSTRACT FROM AUTHOR]

Mannheimia haemolytica infection is one of the most common etiologic agents of sheep pneumonia almost all over the world. Ovine pneumonic Mannheimiosis is characterized by severe fibrinous pleuropneumonia. Subacute to chronic cases progress to purulent bronchopneumonia and its squeals include abscessation and fibrous pleural adhesions. In the present study, lungs of 8986 sheep were inspected grossly in the Ahvaz abattoir and totally 65 lungs with visible signs of bronchopneumonia were selected for pathological and bacteriological examinations. Mannheimia haemolytica antigens were detected in 63.07% of immunoperoxidase stained tissue sections while 52.30% of the lungs were positive in bacteriological culture. Suppurative, necrotic and fibrinous types of bronchopneumonia were the most abundant lesions and right cranial lobes, specifically their cranial portions, were the most affected areas. McNemar test showed a significant difference between the diagnostic power of immunohistochemistry (IHC) and bacterial culture in detection of M. haemolytica (κ=0.66). Considering IHC as a golden test, sensitivity and specificity of bacterial culture were estimated as 78.05 and 91.67%, respectively. Chi- squared test showed significant correlations between the distribution of the lesions and bacterial isolation (P=0.04), types of lesions and IHC results (P=0.01), and also types of bronchopneumonia and mixed/pure isolation (P=0.008). This study showed the significant role of Mannheimia haemolytica in causing pneumonic lesions of studied sheep. [ABSTRACT FROM AUTHOR]

Quorum quenching (QQ), the enzymatic degradation of N-acyl homoserine lactones (AHLs), has been suggested as a promising strategy to control bacterial diseases. In this study, 10 AHL-degrading bacteria isolated from the intestine of barramundi were identified by 16S rDNA sequencing. They were able to degrade both short and long-chain AHLs associated with several pathogenic Vibrio species (spp.) in fish, including N-[(RS)-3-Hydroxybutyryl]-l-homoserine lactone (3-oh-C4-HSL), N-Hexanoyl-l-homoserine lactone (C6-HSL), N-(β-Ketocaproyl)-l-homoserine lactone (3-oxo-C6-HSL), N-(3-Oxodecanoyl)-l-homoserine lactone (3-oxo-C10-HSL), N-(3-Oxotetradecanoyl)-l-homoserine lactone (3-oxo-C14-HSL). Five QQ isolates (QQIs) belonging to the Bacillus and Shewanella genera, showed high capacity to degrade both synthetic AHLs as well as natural AHLs produced by Vibrio harveyi and Vibrio alginolyticus using the well-diffusion method and thin-layer chromatography (TLC). The genes responsible for QQ activity, including aiiA, ytnP, and aaC were also detected. Analysis of the amino acid sequences from the predicted lactonases revealed the presence of the conserved motif HxHxDH. The selected isolates were further characterized in terms of their probiotic potentials in vitro. Based on our scoring system, Bacillus thuringiensis QQ1 and Bacillus cereus QQ2 exhibited suitable probiotic characteristics, including the production of spore and exoenzymes, resistance to bile salts and pH, high potential to adhere on mucus, appropriate growth abilities, safety to barramundi, and sensitivity to antibiotics. These isolates, therefore, constitute new QQ probiotics that could be used to control vibriosis in Lates calcalifer. [ABSTRACT FROM AUTHOR]

Objective: Red seaweeds are the sources of polyanionic polymers that play a foremost role in ionic, mechanical and osmotic functions. The carbohydrate elements of marine algae are found in the extracellular matrix. The Gracilaria polysaccharides have antitumor and antiviral activity and minimize stress. Although algae polysaccharides modulate a large number of biological activities, the antimicrobial activity has been rarely reported. Material and Methods: The G.corticata tissue was submitted to mechanical stirring for 6 h at room temperature (25°C) in HCL 0.1 M at 10% (w/v). The suspension was filtered and the solution was neutralized with 0.5 M NaOH. The solution was then centrifuged and two volume of ethanol was added to the upper part. The supernatant dissolved and dialyzed against phosphate buffered saline. The extract was fractionated on DEAE-C column by NaCl gradient. The obtained fractions were dialyzed against water and analyzed for carbohydrate contents. The antimicrobial activity of each fraction was evaluated by micro-dilution method against six bacteria including: Staphylococcus aurous, Escherichia coli, Methicillin-resistant Staphylococcus aureus (MRSA), Salmonella typhimurium, Pseudomonas aeruginosa and Aeromonas hydrophila. In addition, the obtained fractions were orally administrated 100μg/day for 7 days to 10 groups of 4 adults NMARY mice. The effects of various fractions on some of immune response index as antibacterial and complement activity of serum and humoral immune response against sheep red blood cell were evaluated. Results: In-vitro analysis showed that, out of the 10 fractions which obtained from Gracilaria extract, the most of them have antibacterial effects; however oral administration of the fractions have no significant effects on antibacterial and complement activity of mice serum. The fraction 1, 2, 5, and 6 significantly induced the humoral immune response against SRBC. Conclusion: The antibacterial activity of the fractions may be neutralized in gastrointestinal tract. The more research would be performed to purify the effective materials and clarify the reason of humoral immune response induction. [ABSTRACT FROM AUTHOR]

Mycobacterium avium subsp. paratuberculosis heat shock protein 70 (MAPHsp70) is an immunodominant antigen, which can be used as a subunit vaccine against bovine paratuberculosis. In the present study, we evaluated the immunogenic activities of MAPHsp70 expressed by DNA vaccine in chicken and the use of prepared specific avian IgY antibodies for western blotting and ELISA methods. The gene encoding MAP Hsp70 was subcloned into the eukaryotic expression vector, pcDNA3.1, and the recombinant plasmid (pcDNA3.1-MAP Hsp70) transfected into COS-7 cells. Chickens were also immunized with pcDNA3.1-MAP Hsp70, and egg yolk antibodies extracted from eggs were collected after immunization. DNA-designed IgY antibody was used in Western blotting analysis to detect the expression of MAPHsp70, and in a sandwich ELISA to assess the prevalence of anti-MAPHsp70 antibodies in cattle serum. Western blotting results indicate the expression of rMAP hsp70 in COS-7 cells and sandwich ELISA could detect anti-MAPHsp70 antibodies in 7.5% of cows. Chicken immunization with pcDNA3.1-MAPHsp70 could demonstrate the effective production of anti-MAPHsp70 IgY antibodies. Monospecific anti-MAPHsp70 antibody generated in chickens is useful for detection of MAPHsp70 peptide in cell culture and MAP lysate.