جستجوی مقالات مرتبط با کلیدواژه « مقاومت دارویی » در نشریات گروه « دامپزشکی »

Escherichia coli is one of the most common pathogens in poultry that causes Colibasilosis. Until now many Extended-spectrum beta-lactamases (ESBLs) were identified that we can refer to SHV and OXA that they are coded by blaSHV and blaOXA, respectively. Regarding the development of antibiotics resistance and harmful effects of resistant bacteria on beta-lactam antibiotics, they can have an effect on human health and animal health, and due to the high mortality rate of disease, reducing production, as well as damage caused by drug use, it’s very important to control and prevention this disease. In the present study, 50 isolates of Escherichia coli were collected from 60 cloacal swabs from broiler chicken farms between 7 to 21 days old in Zabol. Antibiogram test was performed by disk diffusion method to investigate drug resistance to Ceftriaxon, Cefazolin, Ceftizoxime, Cephalothin, Ceftazidime and Cefixime. Besides, the frequency of blaSHV and blaOXA were investigated by PCR. The results showed that the highest resistance was to Cefazolin (80%) and the lowest resistance was to Ceftriaxon (8%). The frequency of blaSHV and blaOXA genes in Escherichia coli isolates was 24% and 0.0%, respectively.

The aim of this study was to survey the infectious lesions of liver and heart of commercial poultry carcasses caused by bacteria, to assess the role and the rate of incidence of bacteria other than E. coli in development of liver and heart lesions in commercial poultry flocks, and to determine the antimicrobial sensitivity of the isolated bacteria. Samples were taken from heart blood and liver’s visceral surface of 614 carcasses obtained from 150 flocks (including 118 broiler flocks, 14 laying flocks, 12 turkey flocks, 2 breeder flocks, 2 quail flocks and 2 partridge flocks) located in 18 provinces of Iran. The bacterial isolates were classified into genus and species based on microbiological standard methods. Out of 484 isolates, 382 (78.92%) Escherichia coli, 37 (7.64%) Salmonella, 18 (3.71%) Proteus, 17 (3.51%) Staphylococcus aureus, 9 (1.85%) Streptococcus, 7 (1.44%) Pseudomonas aeruginosa, 6 (1.23%) Klebsiella, 5 (1.03%) Staphylococcus epidermidis and 4 (0.71%) negative coagulase Staphylococci were detected while in 165 cases, no bacteria were found. Salmonella was detected in a young turkey flock (7-day old). Antimicrobial sensitivity test was performed for 100 E. coli isolates from broiler flocks, 2 E. coli isolates from quail flock and 30 Salmonella isolates. The resistance pattern of E. coli isolates included 56 patterns. The highest drug resistance was observed to doxycycline, flumequine, tetracycline and enrofloxacin. In 30 salmonella isolates, 17 resistance patterns were observed. The highest drug resistance was observed to ampicillin and nalidixic acid. All Salmonella isolates belonged to serogroup D. Results showed that Escherichia coli was the most common pathogen isolated from heart and liver lesions but other bacterial infections should also be noticed. Drug resistance patterns even in isolates of one farm may vary; therefore, performing antimicrobial sensitivity test is necessary prior to prescribing any antibacterial agent in a farm.

Contagious equine metritis (CEM) is one of the highly communicable venereal diseases of horses, caused by the bacterium Taylorella equigenitalis. That is responsible for great economic damage to the horse breeding club. In addition to T. equigenitalis as a most important causes of infertility, other bacteria can also cause infertility.The aim of this study was to isolate and determine the antibiotic resistance pattern of bacteria from the genital tract of Turkmen mares by emphasizing the isolation of T. equigenitalis in Kalaleh. In this study, 52 samples were randomly taken from the clitoria fossa and sinuses of mares. After performing standard biochemical and microbiological tests, antibiotic susceptibility testing was performed by disk diffusion method according to CLSI instructions. Two methods of culture and PCR were used to identify T. equigenitalis. T. equigenitalis was not isolated from any of the samples by culture and PCR methods. A total of 91 bacterial strains were isolated, which were: 22% Staphylococcus aureus, 21% Escherichia coli, 14.5% Klebsiella, 12% Vibrio, 11% Shigella, 9% Pseudomonas aeruginosa, 9% Corynebacterium and 2.5%, respectively. Enterococcus. Gram-negative and Gram-positive isolates showed the highest antibiotic resistance to vancomycin (50.8%) and penicillin (60%), respectively. All isolates were sensitive to the antibiotics neomycin, trimethoprim / sulfamethoxazole and amikacin (100%). In this study S. aureus and E. coli had the highest frequency among isolates and T. equigenitalis was not considered as a cause of infertility in Turkmen horses in Kalaleh.

Integrons are mobile genetic factors that are able to carry resistance gene in some bacteria like Escherichia coli. Drug resistance study in pathogenic bacteria is important. The aim of this study was to investigate the prevalence of integron class 1 and antibiotic susceptibility pattern in Escherichia coli strains isolated from broilers with colibacillosis infection. A total of 100 Avian Pathogenic Escherichia coli (APEC) were isolated from the lesions of the birds suspected to colibacillosis by sampling aseptically from internal organs. All isolates of Escherichia coli were confirmed by biochemical tests. To evaluate antimicrobial resistance, the disc diffusion method on Mueller-Hinton agar was used in accordance with the Clinical and Laboratory Standards Institute (CLSI) guidelines by using of seven antibacterial paper discs. The DNA of these isolates was extracted by a boiling method and was screened for the presence of class 1 integron gene by conventional polymerase chain reaction (PCR). Antimicrobial resistance test showed resistance to nalidixic acid (100%), tetracycline (96%), ciprofloxacin (91%), norfloxacin (88%), lincospectin (53%), cefuroxime (50%) and gentamicin (17%). Furthermore, 97% of the isolates contained integron class 1. According to the results of this study, there is high prevalence of integron gene in Escherichia coli isolated from colibacillosis lesions. Besides, high prevalence of drug resistance was observed among the isolated pathogenic Escherichia coli.

During the last two decades, anthelmintic drugs have been increasingly applied against gastrointestinal parasites of sheep in Iran.

For this purpose, drug resistance to albendazole (Alb) and fenbendazole (Feb) in gastrointestinal nematodes in sheep of Saqez multiplicity was assessed.

In in-vivo experiment, a total number of 90 sheep in three groups (30 sheep/group) with EPG≤150 were examined for nematode resistance to Alb and Feb. They were treated with Alb and Feb or untreated (as a control group).

There was significant difference between Alb and Feb treated groups and control group. The EPG in Alb, Feb and control groups was 59.8±1.93, 18.8±1.258 and 204.07±4.81, respectively. There was drug resistance against Alb in compassion with control group (R=71%). There was suspicion drug resistance for Feb in comparison with control group (R=90.66%).

From the results of the present study, it was concluded that there was absolute and suspected drug resistance against Alb and Feb in sheep of Saqez municipality, Iran, respectively.

Non-typhoid Salmonella spp. are recognized as one of the major food-borne pathogens with more than 2500 serotypes worldwide. This survey was done to determine Salmonella infection among broiler flocks in Mazandaran and Gilan Provinces, as among the most important poultry production centers in Iran. Thirty-five Salmonella isolates were recovered by standard bacteriological methods from 13310 manure samples (1331 pooled samples) collected from 126 broiler houses in different ages. Slide agglutination tests were performed using Salmonella somatic O poly antisera form each of A to E antisera. The occurrence rate of infection was 26% among 126 houses. It was found that 17 (48.57%) and 18 (51.43%) isolates belonged to groups D and C, respectively. The occurrence and the level of antimicrobial resistance patterns in 35 Salmonella isolates were also determined. Thirty-two different patterns of resistance were found among 35 isolates. The highest resistance was observed to erythromycin, vancomycin, clindamycin, penicillin, doxycycline, colistin, oxytetracycline, carbenicillin, furazolidone and tetracycline. The highest percentage of sensitivity (100%) was found to ceftriaxon, danofloxacin, levofloxacin, imipenem, ofloxacin, cefazolin and amoxicillin. All isolates were found to be multi-resistance. In the other words, all isolates were resistant against one to three antimicrobials tested. The high prevalence of multidrug resistance found in this study may be attributed to widespread usage of antimicrobial agents in domestic animals especially poultry industry in Iran. There is a serious implication for public health by transmitting resistant bacteria to human via food chain.

Fish mycobacteriosis is a chronic progressive disease that caused by different species of mycobacteria. Diagnosis of the disease in ornamental fish is usually done by bacterial culture and histopathology. Identification is also based on the rate of growth at different temperature, the pigmentation type, the morphology of colony and by biochemical tests. Although the primary diagnosis of fish mycobacteriosis is based on clinical symptoms and the presence of granuloma in visceral tissues by sampling, but in some cases no any clinical symptoms or no granulomas masses are seen. Due to the zoonotic character of the disease, increasing importance of aquariology, and also increasing of opportunistic infections via Non-tuberculous mycobacteria in older persons or immunocompromised patients, also existence of some extremely difficulties to treat like to require the long course of therapy, and on the other hand, the financial losses, so; the present study planned to detection and identification of mycobacterial species in aquarium fish. Existence of Mycobacterial species in 53 fishes were investigated that they were obtained from some local aquarium shops in Tabriz by Ziehl-Neelsen staining and culture on Lowenstein-Jensen (LJ) medium. Identification of isolates was done by morphological characters of mycobacteria on LJ and using of biochemical tests. For drug susceptibility testing, the proportional method on LJ were used for isoniazid, ethambutol, rifampin, streptomycin, kanamycin, ciprofloxacin, and amikacin. The susceptible (H37Rv) standard Mycobacterium tuberculosis strain was used as a control. Acid-fast bacilli were detected on the 7 smears of samples by direct microscopic examination of Ziehl-Neelsen. In using of the culture method, Mycobacterium spp. were isolated from 28.3% of the fishes. The isolated species were identified as M. marinum, M. fortuitum, M. smegmatis, M. terrea, M. flavescens and M. asiaticum. The study showed that M. fortuitum and M. marinum are more than other species. In the drug susceptibility testing; the streptomycin had the highest resistance (93.33%) and the lowest drug resistance was diagnosed to ciprofloxacin (20%). In the investigation, Mycobacterium marinum, M. fortuitum, M. smegmatis and M. flavescens that are well known as pathogens in fish and humans were isolated, which were resistant to most drugs that are used in the treatment. Therefore, more attention should be paid to the presence of
mycobacteria in aquarium fish for reducing the rate of bacterial transmission to human.

The use of antibiotics in food animal production systems has resulted in emergence of antibiotic resistant zoonotic bacteria such as Salmonella that can be transmitted to humans through the food chain. This survey was done to determine Salmonella contamination and to evaluate Salmonella drug resistance in broiler flocks as one of the most important sources of food in Golestan province. In this survey, samples were taken from 52 broiler farms (85 broiler houses) at different ages and, in total, 510 pooled manure samples were collected. Standard cultural method was performed for Salmonella isolation. The serogroup of each isolate was determined by using polyvalent and monovalent Salmonella antisera. The occurrence and the level of antimicrobial resistance patterns in Salmonella isolates were determined by disk diffusion method. Fourteen Salmonella were isolated from 510 pooled samples (2.74%). There was occurrence rate 16.47% in 85 houses. Three isolates belonged to group D, 9 isolates belonged to group C and 2 isolates did not belong to serogroups A to D. Thirteen different patterns of resistance were found. All of the isolates (100%) were sensitive to ceftriaxone and cefixime and resistant to nalidixic acid, flumequine, chlortetracycline, tylosin, erythromycin and doxycycline. Multiple resistances to at least four antimicrobial drugs were observed in all isolates. The highest resistance rate was found against most prevalent drugs in poultry industry reinforcing this hypothesis that wide usage of drugs results in the emergence of drug resistant bacteria.

Salmonella infection is a major public health problem in the world and in most parts of the world, particularly in developing countries are of utmost importance. Poultry, human, animal and food play an important role in transmission, economy and public health aspects. Yet studies show that Salmonella enteritidis and Salmonella typhimurium is the predominant serotypes. Due to limitations in isolation in laboratory, using molecular techniques as a rapid, inexpensive, specific and sensitive diagnostic must be used. The source of the infection could be important in the control strategies. Spread of resistance genes via plasmid among different serotypes of Salmonella is of great importance. Identification and prevention of drug resistance genes among serotypes of Salmonella could be one of the most important issues in the study of its ressistance. To determine the susceptibility patterns of isolates, the protocols of treatment can be modified and replaced with effective antibiotics.

The aim of this study was to determine the occurrence and the level of antibiotic resistance patterns in 62 Salmonella isolates obtained from broiler chicken farms in Amol، Iran to common antibiotics in Iranian poultry industry. Antimicroibial resistance testing was performed using 7 useful antibiotics tetracycline، flumequin، lincospectin، florfenicol، neomycin، danofloxacin and enrofluxacin Foty one isolates were belonged to serotype Salmonella enteritidis. We found 17 different patterns of resistance in 62 salmonella isolates and 16 resistance patterns in 41 serotype Salmonella enteritidis. There were 5 resistant isolates to all antibiotics and there was not any sensitive isolate to all antibiotics. The highest and lowest percentage of resistance was found to flumacoin (83. 87%) and danofluxacin (30. 64%). The most frequent pattern of multiresistant isolates was tetracycline + flumequin + lincospectin + florfenicol + enrofluxacin. Multiple resistances were observed in 60 isolates (96. 77%). All isolates were found to be resistant to one or more of the antibiotics tested. The high prevalence of resistance to antimicrobial agents found in this study might be attributed to uncontrolled use of antimicrobial agents in veterinary specially poultry industry in Iran that is serious implication for public health by transmitting resistant strains to human via food chain. Establishment of standardized monitoring systems for determining the occurrence of resistance among food animal for designing Salmonella control program in farms is needed.

Salmonella spp. is Gram-negative bacteria and belongs to entrobacteriaceae family. Salmonella spp. is one of the most important zoonotic agents with worldwide distribution. The aims of this study were to isolate Salmonella from poultry farms around Ghaemshahr city, identify the serotypes, and determine the drug resistance patterns of the isolated Salmonella spp. A total number of 2280 samples were randomly collected from freshly dropped feces of broiler chickens in different flocks. Each 10 samples were pooled and processed for Salmonella isolation according to the standard procedures. Serotyping was performed by slide agglutination test to determine the O and H antigens of the isolates. The antigens included A to D polyvalent, and O2, O4, O5, O9, O12, H2, H6, HL, Hgm monovalent antisera. Antimicrobial susceptibility of the isolates against 30 antimicrobial agents was determined by using standard disk diffusion method. Out of 2280 samples (228 pooled-samples), 30 Salmonella isolates were recovered. Serotyping revealed that two isolates were Salmonella spp. enteritidis and 28 isolates belonged to serogroup C. All 30 Salmonella isolates were susceptible to levofloxacin and Fosbac. Also, the highest resistances were related to streptomycin, furazolidone, nalidixic acid, tetracycline, and lincospectin. Multi-resistance to drugs was common among the Salmonella isolates and ranged between 2 to 17. There were 29 resistance patterns. The results of this study showed the presence of Salmonella spp. infection among broiler chickens in Ghaemshar regions and the occurrence of antimicrobials resistance among the isolates. These findings are important for Iranian poultry industry and of concern to public health.

Salmonellas are the short bacteria, gram negative, without capsule, facultative aerobic and anaerobic. They have high resistance against physical and chemical factors. Salmonella causes white bacillus diarrhea in Avian. It`s transferring in Avian by vertical and horizontal. In human, it causes food poisoning too. The egg is the most important source of salmonella. The native eggs have been collected and transferred to the lab for studying the contamination of them. These eggs are collected from the Fasa (Iran). In this research the pattern of drug resistance of bacteria is studied. The shell of eggs is purified with Ethanol 80%, and then the contents of five eggs are mixed in a dish and are incubated with soap in Selenite-F. After 24 hour incubation at 37ºc the sample of Selenite-F was transferred to salmonella spp. and after incubation at 37ºc was analyzed in the terms of suspected colonies to Salmonella.The suspected colonies were inoculated into lysine decarboxylase broth and TSI agar environment. The bacteria which have reactions were related to salmonella, and they were analyzed by the PCR test, with special primer for salmonella spp. such as S.Enteritidis and S.Typhimurium. The results of this study indicated that the eight samples of mixed Ten (at least 5% of eggs) were contaminated with salmonella of serotype S.Enteritidis. Among the separated Salmonellas 90.3 % were resist to Ampicillin, 15.5% to Tetracycline, and 41.9% to Kanamycin, but all of them were sensitive to Norfloxacin in this anti biotic resistance test.

The aim of this study was to determinate the drug resistance patterns of avian E.coli isolates from cases of colibacillosis in Golestan Province, Iran. One hundred and fifty isolates of E. coli from pericarditis lesions (5 samples per farm and in 30 farms) submitted to the microbiology laboratory. After sampling and confirmation by biochemical reactions, the E.coli isolates were tested for their susceptibility to a panel of 15 antibacterial agents using the Kirby-Bauer disc diffusion method. The drug susceptibility test showed that all isolates were resistant to Nalidixic acid, Erythromycin, Flumequine and were susceptible to Gentamicin and Ceftiofur. More than 80% of the isolates were resistant to Colistin, Tetracycline, Sulfadiazine + Trimethoprim, Enrofloxacin, Cyprofloxacin, Danofloxacin, Lincospectin, Difloxacin, Sulphachlorpyridazin + Trimethoprim and Doxycycline. There were 29 drug resistance patterns among 150 E.coli isolates. Eighty eight percent of isolates belonged to more than one pattern, whereas the rest (12%) of isolates, each isolate belonged to one pattern only. The results of this study confirmed the possibility of indiscriminate abuse and misuse of antibacterial agents in poultry industry and this could be dangerous for public health as well.

In this report, β-tubulin gene polymorphism was investigated in Haemonchus contortus populations isolated from sheep flocks in different regions of Khouzestan province, southwestern Iran. The samples were chosen on the basis of regional variation in benzimidazole treatment background of sheep flocks. Our objective was to study the relationship between treatment background and β-tubulin gene polymorphism of H. contortus isolated from the selected regions. H. contortus isolated from Shooshtar revealed reduction in β-tubulin gene polymorphism restriction fragment length polymorphism (RFLP) in respect to other isolates indicating that benzimidazole-resistant isolates of H. contortus developed in some sheep flock of Shooshtar region.