Veterinary Research Forum

Abstract Mugger crocodile is the only crocodile existing in Iran. The present study was aimed to investigate the bacterial flora in oral and cloacal cavities of wild Mugger crocodiles in Negour protected area, Iran. The isolation and molecular characterization of oral and cloacal bacterial flora were performed in 22 Mugger crocodiles captured in Negour protected area, Iran. Ten bacterial species from all oral samples and six bacterial species from all cloacal samples were recovered. The most commonly isolated bacteria in oral samples were Burkholderia contaminans and Lactococcus garvieae, respectively; whereas, in cloacal samples, it was Lactococcus lactis. It is likely that the isolated bacteria would pose a threat to both crocodiles and humans health. It can threaten crocodiles during stressful conditions; while, humans would be susceptible if they are bitten by crocodiles, consume their meat or spend time near their natural environment. This study provides useful information about bacterial diversity which could help to select the most appropriate anti-bacterial when dealing with infections caused by crocodiles.

Abstract The objective was to investigate the multidrug resistance and presence of class 1 and 2 integrons in 300 Escherichia coli isolates obtained from 20 broiler farms during three rearing periods (one-day-old chicks, thirty-day-old chickens, and one day before slaughter) in Fars, South Iran. Results showed that 81.00%, 82.00%, and 85.00% of isolates were multidrug-resistant on the first day, thirty-day-old chickens, and one day before slaughter, respectively. Multidrug-resistant E. coli isolates were further examined for the presence of class 1 and 2 integrons using PCR assay. The existence of class 1 integron-integrase gene (intI1) was confirmed in 68.40%, 72.70%, and 60.90% of multidrug-resistant isolates from stage 1, stage 2, and stage 3 of the rearing period, respectively. The frequency of class 2 integron-integrase gene (intI2) during the first to the third stage of sampling was 2.60%, 25.50%, and 30.40%. Also, sequence analysis of the cassette arrays within class 1 integron revealed the presence of the genes associated with resistance for trimethoprim (dfrA), streptomycin (aadA), erythromycin (ereA), and orfF genes. The results revealed that percentages of antimicrobial resistance in E. coli isolates were significantly higher in the middle and end stages of the rearing period. In conclusion, widespread dissemination of class 1 integrons in all three stages and rising trends of class 2 integrons existence in E. coli isolates during the rearing period of broiler chickens could exacerbate the spread of resistance factors among bacteria in the poultry industry. Future research is needed to clarify its implication for human health.

Abstract The purpose of the present study was to isolate and identify the pathogenic agents in Acipenser stellatus (Pallas, 1771) and Huso huso, (Linnaeus, 1758) reared in the south of Fars province, Iran which have shown infectious disease signs. Samples from spleen and kidney of 32 fishes showing septicemia symptoms such as decreasing of appetite, unbalanced swimming, expanded wounds, and petechia on the body surfaces, pectoral fins rot, visceral hemorrhage, bleeding on the spleen, and heart ascites were collected. Then samples were cultured on brain heart infusion agar growth media, stain and biological and biochemical tests on purified bacteria were performed. On the other hand, 16S rDNA region of the isolated organism was amplified using PCR. The amplified gene fragment was sequenced and evolutionary history was inferred by phylogenetic tree construction using neighbor-joining method. Results indicated that two bacterial species including Chryseobacterium joostei which isolated from the kidney of stellate sturgeon (43.00%), and Aeromonas veronii which isolated from the spleen of both sturgeon species (75.00% and 31.00% from beluga and stellate sturgeon, respectively), were recognized. Phylogenetic tree analysis showed that Fars isolated organisms including A. veronii and C. joostei had highest similarity with A. veronii bv veronii and C. joostei isolated from France, respectively.

Abstract In this study, molecular characterization of Echinococcus granulosus sample obtained from water buffalo originating from southwest of Iran was performed using comparative sequence analysis of cox1 mitochondrial gene. DNA was extracted from protoscoleces removed from hydatid cyst from the liver of a 2-year-old male buffalo slaughtered in Khuzestan province. Molecular and phylogenetic analyses were conducted based on cox1 mitochondrial gene. We found the presence of a new microvariant of G3 genotype for E. granulosus in Iran which isgenetically differentiated from reference G3 sequence (M84663).The difference was a transition mutation of adenine to guanine in position 214 (A214G) resulting in a substitution of the threonine (ACT) by alanine (GCT). These findings extend the knowledge of heterogeneity and distribution of G3 genotype for E. granulosus in world.

Abstract Five common tetracycline resistance genes tet(A), tet(B), tet(M), tet(O) and tet(S) were studied by polymerase chain reaction in 100 bacteria isolated from Iranian fish farms. In the antibiogram test most of the bacteria were either intermediately or completely resistant to tetracycline. Nine isolates out of 46 Aeromonas spp. contained either tet(A/M/S) resistant genes as follows: tet(A) in A. veronii/sobria (n = 1), A. media (n = 2), A. aquariorum (n = 1), and A. veronii (n = 3); tet(M) in one isolate of A. sobria and tet(S) in 1 isolate of A. jandaei. In other bacteria, tet(A) gene was detected in Citrobacter freundi (n = 1), Pseudomonas putida (n = 1); tet(S) was also identified in Yersinia ruckeri (n = 1), Arthrobacter arilaitensis (n = 1) and P. putida (n = 1). In total, 31 isolates (31.00%) contained the tetracycline resistance genes in which 21 bacteria (21.00%) showed the tet(S), nine bacteria (9.00%) contained the tet(A) and 1 bacteria (1.00%) was positive for tet(M). All of the L. garvieae isolates contained tet(S) in this study. The most widely distributed resistance gene was gene tet(A) and the least known resistance genes was tet(M) among the studied bacteria of the genus Aeromonas in this study.

Abstract A 2-year-old male Pekingese dog was referred to Shiraz University’s Veterinary Teaching Hospital for anorexia and depression. The case had no history of surgery. Physical examination revealed no abnormalities except mild depression and fever. Small, coccoid, epicellular bacteria were detected on erythrocytes by microscopic examination of the Giemsa-stained blood smears. Abnormalities noted in the complete blood count included regenerative anemia characterized by a marked reticulocytosis. Examination of the plasma showed visual evidence of slight intra vascular hemolysis. In addition, Howell-Jolly bodies, nucleated RBCs, increased immature neutrophils and thrombocytosis were found in this case. The urine was strongly positive for bilirubin, and the urine sediment had abundant bilirubin crystals. For polymerase chain reaction (PCR) purpose, total DNA was extracted from blood sample collected from dog. PCR was positive and phylogenetic analysis of concatenated data showed our isolate clustered within Candidatus Mycoplasma hematoparvum group. Treatment was performed by oral ciprofloxacin and prednisolone. The clinical signs improved after three days. Two month follow-up showed no recurrence. In conclusion, hemoplasmosis should be considered as a differential diagnosis in dogs with hemolytic process and pyrexia. The PCR evaluation for hemoplasma DNA should be included in the investigation of such cases to enable the rapid detection of this infection, which may be more common than previously estimated. Besides, ciprofloxacin might have an effect on treatment of hemoplasma in dogs, however, conducting further case studies are necessary to recommend successful treatment.