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Mycoplasma gallisepticum (MG) is a contagious avian pathogen that causes financial losses to the poultry industry. Isolation of the pathogen is difficult and time-consuming, and therefore, far from a routine method. Serological testing methods to detect antibodies resistant to MG are widely used in routine diagnosis. Tylosin is a class of macrolide antibiotics tremendously administered in veterinary medicine for the treatment of mycoplasmosis and prophylaxis. This study aimed to detect MG by immunoassay testing, culture, and polymerase chain reaction (PCR) in commercial poultry farms and to investigate the tylosin susceptibility of the isolates. To verify the presence of antibodies resistant to MG, 750 blood samples were randomly collected from 38 broiler farms from 2019 to 2022 in Mazandaran and Golestan provinces, Iran, and rapid slide agglutination (RSA) assay was performed. Positive results were analyzed by the enzyme-linked immunosorbent assay (ELISA) for further investigation. Here, 920 swab samples were collected from 38 non-vaccinated commercial farms for culture, and PCR tests were performed for the isolated strains. The activities of tylosin were tested in vitro against these isolates using the broth microdilution method. The lowest antibiotic concentration that resulted in a color change was considered the minimum inhibitory concentration (MIC) value. Twenty-four (63.1%) farms were positive in the RSA test, and 21 (55.2%) farms were positive in the ELISA test. Nine (23.68%) of the farms grew on culture media, and 8 (21.05%) were detected as Gallisepticum species by PCR. The geometric mean of MIC for tylosin was 5.75 µg/ml, MIC50 was 4 µg/ml, and MIC90 was 8 µg/ml. The results indicated that commercial farms were infected with MG. Considering the ability of MG to spread and the probable use of the RSA test as a rapid and cheap method, it can be argued that ELISA and RSA serological tests can be used to find MG in poultry flocks, and the positive result should be confirmed by standard microbiological tests or PCR. It was also found that the isolated parts of MG changed their sensitivity to tylosin, indicating the need for routine testing to optimize treatment dose and efficiency. [ABSTRACT FROM AUTHOR]

Background: Consumption of contaminated eggs with Salmonella enterica serotype Enteritidis (SE) cause gastroenteritis in human. Aims: The present study examined the effect of probiotic and prebiotic compared to antibiotic on the colonization of SE in the ceca, and the quantity and quality of produced eggs in the laying hens challenged with SE. Methods: One hundred Hy-Line W-36 laying hens with 44-week-olds were studied for 13 weeks in a randomized complete block design containing five treatments and four replicates with five birds in each replicate. Treatments included: negative control, positive control, and antibiotic: diets containing antibiotic (Oxytetracycline 0.15 g/kg diet), probiotic (Bactocell® 0.1 g/kg diet), and prebiotic (Diamond V Original XPCTM 1.25 g/kg diet). All experimental groups except negative control were challenged with 1 ml of suspension solution containing 1 × 107 CFU/ml SE by oral gavage at the start of the ninth week of the experiment. Laying performance traits and cecal bacterial population were measured at the end of each week. Results: Probiotic and prebiotic showed a greater effect in the reduction of yolk cholesterol and blood cholesterol level before and after challenge with SE, respectively (P<0.05). In pre-challenge period, treatments had no effect on the cecal bacterial population; but after the challenge, three dietary supplements decreased the colonization of SE in the ceca of laying hens, and prebiotic showed more preventive effect (P<0.05). Conclusion: The result of this study showed that the prebiotic can be effective in reducing and preventing SE colonization in laying hens and act as an alternative to antibiotics. [ABSTRACT FROM AUTHOR]

Background: Salmonellosis is one of the most important zoonotic diseases in humans and animals worldwide. Aims: The main objective of this study was to report serovars, clonal relatedness, and antimicrobial resistance of Salmonella strains isolated from human, different animal hosts including pigeons, broilers, cattle, camel, parrots, and hamsters in different regions of Iran. Methods: Twenty-four Salmonella isolates were confirmed at the genus level by biochemical tests and polymerase chain reaction (PCR) by showing the presence of invA gene. Serovars were determined and their clonal relatedness was assessed by RAPD-PCR and antibiotic resistance profiles. Results: Overall, Salmonella Typhimurium was the most prevalent serovar (45.8%, 11/24), which was recovered from humans, pigeons, and camels. Salmonella Enteritidis (29.2%, 7/24) was the second common serovar that was recovered from cattle, broilers, humans, and hamsters. Salmonella Infantis (12.5%, 3/24) belonged only to broiler sources, and Salmonella Seftenberg (12.5%, 3/24) was isolated from eggs and a parrot. The major RAPD pattern was VI (33.3%) in which the two S. Typhimurium isolates (belonged to humans and pigeons) exhibited similarity in both RAPD pattern and resistance profile. Antimicrobial susceptibility test showed full resistance to tylosin and erythromycin (100%, 24/24). All isolates (100%, 24/24) were susceptible to ceftriaxone, cefixime, and gentamicin. In total, 75% of the isolates were multi-drug resistant (MDR) and revealed 15 different antimicrobial resistance profiles (R-type). Conclusion: This study supports the potential transmission of Salmonella serovars via animal contacts. Thus, it is necessary to establish a national systematic monitoring program with one health approach for controlling Salmonella infections. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the utility of urinalysis and dipstick results in predicting leptospiruria in dogs. Ninety dogs, regardless of health status, were included in this study since January to August 2008. All the dogs went through a complete physical examination, and urine samples were collected by catheter or by cystocentesis. Polymerase chain reaction (PCR) testing was performed on urine samples to detect leptospiral DNA. Urinalysis was done at the same time. Of the 90 dogs included in the study, 28 (31%) were diagnosed as shedding leptospires in their urine. In terms of urinalysis test results, no significant difference was found between dogs with or without leptospiruria. Indeed, most of the dogs with positive PCR assay had normal urinalysis findings. The present study suggests that using urinalysis or dipstick is not recommended for screening the dogs that are actively shedding leptospires in their urine. [ABSTRACT FROM AUTHOR]

Diseases caused by Salmonella serovars are wellrecognized in humans, livestock, and zoo animals and can result in morbidity, mortality, and significant economic losses. Salmonella serovars have found greater significance due to their ubiquitous distribution, growing number of serovars, wide host range, complex pathogenesis, and complicated epizootiology involving humans, animals, and the environment. The prevalence of Salmonella serovar infection were determined in 64 animals comprising small mammals (rodents, rabbits, squirrels, hamsters, and guinea pigs) and reptiles (turtles and lizards) in Tehran, Iran. Samples were collected by rectal or cloacal swabs from fresh feces or reptile's water source, as well as from the internal organs of dead reptiles. All samples were enriched in broth media then inoculated in the selected medium and streaked for isolation, which were then subjected to biochemical tests using standard procedures. The DNA of isolated Salmonella was extracted and used for identification of invA gene in Salmonella serovars with S141 and S139 primers. Four salmonella serovars were isolated: two from turtle livers, one from a turtle's water source, and one from a rabbit fecal sample. All samples showed the biochemical profile of Salmonella and also invA gene using the polymerase chain reaction method. Rodents and reptiles were found to be potential carriers of pathogenic Salmonella in humans and animals. [ABSTRACT FROM AUTHOR]

Aims: To identify, clone and sequence the iss (increased serum survival) gene from E. coli strain χ1378 isolated from Iranian poultry and to predict its protein product, Iss. Methods and Results: The iss gene from E. coli strain χ1378 was amplified and cloned into the pTZ57R/T vector and sequenced. From the DNA sequence, the Iss predictive protein was evaluated using bioinformatics. Iss from strain χ1378 had 100% identity with other E. coli serotypes and isolates from different origins and also 98% identity with E. coli O157:H7 Iss protein. Phylogenetic analysis showed no significant different phylogenic groups among E. coli strains. Conclusions: The strong association of predicted Iss protein among different E. coli strains suggests that it could be a good antigen to control and detect avian pathogenic E. coli (APEC). Significance and Impact of the study: Because the exact pathogenesis and the role of virulence factors are unknown, the Iss protein could be used as a target for vaccination in the future, but further research is required. [ABSTRACT FROM AUTHOR]

The aim of this study was to use the immunomagnetic separation (IMS) test plus a multiplex polymerase chain reaction (m-PCR) assay to detect Salmonella at genus level and also for the identification of Salmonella enterica serovar Typhimurium in bovine diarrhoeic fecal samples. In all, 400 bovine diarrhoeic fecal specimens were examined by conventional bacterial culture, IMS, and m-PCR. For m-PCR assay, four set primers were selected: 139-141, specific for inv-A gene of Salmonella spp and the RfbJ, FliC and FljB, specific for the rfbJ, FliC and fljB genes of Salmonella Typhimurium or other Salmonella serovars with similar antigenic properties. Thirty-three (8.25%) out of the 400 fecal samples were culture positive for Salmonella serovars. Of these, 66.7% (22 of 33) were Salmonella enterica serovar Typhimurium, and 9.1% (three of 33) were serovar Dublin. In the IMS + m-PCR, four amplified product (663, 526, 284 and 183 bp) were found in all specimens that had serovar Typhimurium (4,5,12:i:1,2), they corresponded, respectively, to the rfbJ, fljB, inv-A and Flic genes of this serovar. In serovar Dublin (1,9,12:g,p:-), Georgia (6,7:b:e,n,z(15)) and, Enteritidis (1,9,12;g,m:-) only one PCR product (284 bp) was amplified from the inv-A gene. In serovars Augustenborg (6,7:i:1,2) and Lindenburg (6,8:i:1,2) three positive bands (526, 284 and 183 bp) were amplified corresponding to the fljB, inv-A and Flic genes, respectively. In serovar Virchow (6,7:r:1,2) two amplified products (284 and 526 bp) from the inv-A and FliC genes were observed. In serovar Gloucster (1,4,12(27):i:1,w) three fragments (183, 284 and 663) from the FliC, inv-A and, rfbJ genes respectively, were observed. In the positive control as expected, four PCR products were amplified corresponding to the FliC, inv-A, fljB and rfbJ genes, respectively. In conclusion, the results of this study showed that detection of Salmonella at genus level with universal ST139-141 primers and identification of Salmonella Typhimurium by using specific primers of O4, H(2):1, 2 and H(1) antigens can potentially permit to more readily evaluate fecal and other types of samples for the presence of these organisms. Compared to bacteriological culture the combination of IMS and m-PCR resulted a faster method for the detection and identification of Salmonella at genus and serovar level by using of universal and specific primers.