نشریه تازه ها در میکروب شناسی دامپزشکی
سال یکم شماره 1 (بهار و تابستان 1397)

Bacterial have caused the outbreak of diseases more than any other pathogens that are transmitted by food. The aim of this study is to evaluate the extracts of the medicinal plants, saffron, yarrow, thyme and rosemary on the bacteria Escherichia coli, Listeria monocytogenes, Salmonella typhimurium, and Staphylococcus aureus. Antimicrobial effects of hydro-ethanol extract on the bacteria was surveyed using diffusion method in a culture medium Mueller-Hinton agar by paper discs (6 mm) based on Bauer and Kirby instructions. The antibiotics ciprofloxacin, amikacin, gentamicin, azithromycin, trimethoprim-sulfamethoxazole, ceftriaxone, penicillin and ampicillin were used as positive control. Means square was conducted by Least Significant Difference (LSD) test at five percent of probability level (P<0.05). Myrtus Extract is the most effective medicinal plant on the bacteria Listeria, Salmonella typhimurium and Staphylococcus aureus, respectively; with an average of 2.5±0.43, 1.67±0.25 and 2.33±0.66 cm the diameter of bacterial inhibition zone. Rosemary Extract is the most effective medicinal plant on the bacteria E.coli, respectively with an average of 1.25±0.66 cm the diameter of bacterial inhibition zone. Comparison of the effect of plant extracts with antibiotics was used in this research, and it was found that most of the extracts were more effective than ampicillin and penicillin on the bacterium E. coli. Myrtus extract, compared with all antibiotics, was more effective on bacteria Listeria monocytogenes, Salmonella typhimurium, and Staphylococcus aureus. According to the results and increasing resistance to antimicrobial synthetic materials; Myrtus, and after that, rosemary plant can be as effective in destroying some bacteria like; E.coli, Listeria monocytogenes, Salmonella typhimurium and Staphylococcus aureus.

Protozoan parasites of Pyroplasma, due to the illness and death of domestic animals, and the importance of the transfer of some of its genus and species to humans, cause many economic and health damages around the world it turns out. Diseases caused by Theileria and Babesia every year in different parts of our country during the spring and summer season with the beginning of the season, even in early autumn, prevalent in domestic animals. The purpose of this study was to determine the prevalence of blood parasites in susceptible cows in jaundice in Torbat Jam city. This study was conducted in spring and summer of 1394 on 210 suspected yellow fevered cattle in this city. After the clinical examination and observation of clinical signs, he developed blood from the vein to examine the parasites. The blood spread was stained with Giemsa color and studied by optical microscope. The results of this study showed that 36% of the studied cows were infected with Theileria and 6% infected with Babesia and 10% infected with Anaplasma and 8% of the infected Theileria and Anaplasma were observed. Therefore, in view of the presence of blood parasites in the region of the cows and the importance of arthropods in their transmission, it is possible to combat these arthropods in order to control the above-mentioned contaminations, in addition to treating suspected contaminated animals.

Bovine mastitis is one of the epidemic diseases in dairy cattle, that it was created by various infectious agents. The aim of this study was tracking of these bacteria in the cases such as bovine subclinical and clinical mastitis and studying of virulence factors of this bacteria. Overall, 130milk samples were collected from dairy cattle's in the Chaharmahal and Bakhtiyari state scale that they are affected to mastitis and then they were isolated microbial culture and molecular confirmation of Klebsiella pneumonia strains, Presence of the most prevalent of virulence factors in these strains was detected by PCR method. Of 130milk samples examined, 30 samples were positive (15.38%) to Klebsiella pneumonia. Of these strains, the most of virulence factors were detected in this bacteria: so that fimH and papA genes by excess of 65and 90% had the highest prevalent and sfa/focDE gene with 15% presence had the lowest rate of evaluation virulence gene in this isolates. Presence of kinds of virulence factors in the Klebsiella pneumonia isolates will have indicated direct intervention these factors for bacterium pathogen and it is needed to detection of Klebsiella pneumonia pathogen, it must study presence distribution of virulence factors.

Acinetobacter species has a large spread and there are also hypotheses about the transfer of this bacterium from food to humans. Eggs are always among the most widely consumed and richest sources of human food. This study was conducted to evaluate the prevalence and antibiotic resistance of Acinetobacter Bergemini in indigenous and industrial eggs. In this regard, a total of 100 samples of native and industrial eggs were collected from the cities of Chahar Mahal o Bakhtiari province. A total of 200 specimens were prepared from the shell and their contents, and were examined according to the standard method after culture in specific environments for the presence of Acinetobacter Bumann. The suspicious colonies were subjected to PCR for definitive identification. Of 200 shell samples and egg contents, 2 samples (1%) were diagnosed with Acinetobacter Bumann. After performing the antibiotic test, it was found that both samples tested against tetracycline and resistant gentamicin antibiotics were resistant to resistant cytomeptromycin and a semi-susceptible sample, and a sample of susceptible Carbenicillin and one sample Half sensitive. According to the available evidence, egg contamination with Acinetobacter baumeni occurs mainly through environmental factors and secondary contaminants. Failure to pay attention to the necessary points during the production, supply, storage and consumption of eggs can lead to bacterial transmission to the consumer. Therefore, it seems to be possible to prevent transmission of human infection with timely monitoring and observance of hygiene at all stages of the disease.

Salmonellosis is one of the most important case of zoonotic diseases with global distribution. Rural dogs may not show clinical signs of Salmonella infection. Feces of nearly all-animal species including dogs may serve as a potential source of Salmonella infection to humans and even to other animals. Due to the increase in dog keeping among the people especially those living within the rural regain in Sistan, there is an increased risk of transmission of Salmonella infection to humans. The aim of this study is to determine the carrier status of Salmonella in dogs and their role as potential sources of infection to humans. In this research, rectal swabs of 250 asymptomatic rural dogs from Zabol rural regains were cultured in general and specific media, identified by using common laboratory tests and evaluated by PCR using universal at the genus level. Salmonella isolates were tested for antimicrobial susceptibility applying standard methods. In this study, 58 isolates of Salmonella were identified from 250 rectal swabs. The highest resistance was to antibiotics co-trimoxazole, gentamycin, tetracycline and nalidixic acid. Isolation of Salmonella spp. from asymptomatic dogs makes them dangerous source of Salmonella and a treat for human and animal health.

Chicken meat is one of the high-freshness foods and is capable of keeping it in refrigerated conditions for 3 days. Four chicken slaughted day under sterile conditions, 24 samples of chicken meat (fillet) 70 gram per samples were prepred. The samples were immersed in 4% gelatin films with three concentrations of essential oil of cumin (0.3.0.6.0.9) and 0% control group of essential oil of cumin under refregrator conditions. Aerobic bacteria, Psychrophile bacteria, Anthrobacteriaceae, Pseudomonas and lactic acid bacteria and organoleptic properties were studied in these groups during 0, 2, 4, 7 and 12 days. The results showed that with the increasing use of essential oil of cumin, the number of enterobacteriacea, pseudomonas, lactic acid, mold and yeast and total number of bacteria decreased, and especially with concentrations of 0.6 and 0.9, decrasing was more significantly. In the sensory evaluation of chicken's color and odor, the unpopularity was evident from the seventh day onwards. The best 4% gelatin film (due to the smell and taste of cumin essential oil) is recommended at 0.6% cumin essential oil and 7 days in refregrator conditions.

The birds produce IgY immunoglobulin in their egg yolks, which is equivalent to the mammalian IgG. In this study, we investigated the quality and quantity of antibody in egg yolks of some domestic and ornamental birds.

Eggs of six different species of domestic and ornamental birds after disinfection and weighing of the yolk content were examined and the content of yolk fat was separated. The serum level was recorded and two consecutive levels of antibody precipitation with ammonium sulfate were followed and after dialysis, the antibody was extracted. At the final stage, the OD value were calculated and analyzed for each samples, separately.

Estimated weight average of geese, ducks, native chicks, pigeons, quail and chicken eggs were 145.5, 62.7, 57.4, 19.5, 12.4 and g 1.6, and the weight percentage of yolk/ egg were 0.32, 0.31, 0.23, 0.16, 0.21 and 0.21, respectively. The serum levels were observed as 52 ml, 12.5 ml, 15 ml, 3.75 ml, 3 ml, 5.1 ml, respectively. The results of the concentration of antibody to each egg were 60450 μg / ml, 10631.25 μg / ml, 12026 μg / ml, 5203 μg / ml and 2535 μg / ml in OD280, respectively.

The results showed that the highest antibody production is related to geese and in next turn is for native chicken. Also, the use of quail egg as chicken egg alternative could be advisable.

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.

Vibrio fluvialis causes disease and significant economic losses in breeding fish. This bacterium is considered as a human pathogen and several species of marine spawning fish. The egg yolk immunoglobulin technology (IgY) has been used to control many microbial infections. The purpose of the present study was to evaluate the vaccine prepared from V. fluivialis bacteria after injection into laying hens. V. fluvialis was admixed by 0.05% formaldehyde after culture in a liquid medium. Then, the pathogen along with Freund’s adjuvant was injected to the Hyline W36 hens as a vaccine for 7 days. Increase of the weight of the hens was measured until Physical maturity and egg production. Then, an Indirect ELISA was designed to detect IgG Anti V. fluivialis. Injection of the vaccine had no significant effect on weight gain of hens and the number and weight of eggs during the experiment. ELISA test showed that antibody titers in the serum of hyper-immunized hens after injection of the fourth booster reached 1: 12800. According to the results obtained and the results of studies by other researchers, egg yolk antibody (IgY), which is the same as IgG, has been shown to inhibit the pathogenicity in lab and farm animals.

Maternal antibodies are transferred from hens to their offWinter through the egg yolk where the antibody is absorbed and enters the circulatory system. Passive immunity via maternal antibodies can lessen the effects of clinical diseases in chicks or prevent the incidence of them. Haemagglutination inhibition (HI) test is one of the popular assays for detection of Newcastle disease virus (NDV) and Avian influenza virus (AIV) infections. Newcastle disease and avian influenza disease are very important contagious infections which causes vast economic losses to poultry industry. In this study, antibody titres against NDV and AIV measured in serum of breeders, egg yolk, and day old chicks by HI method. NDV and AIV antibodies compared in serum of breeders and egg yolk of the flock. Level of antibodies in the first, third, 6th, 9th, 14th, and 18th days of incubation measured and compared. These values compared with antibody levels of day old chicks. In another experiment, NDV and AIV injected to eggs via allantoic cavity of eggs. EID50 test was used to compare the eggs with NDV and AIV antibodies and the eggs without antibodies (SPF eggs). There was no significant difference in NDV and AIV titres in serum of breeders and egg yolk samples (P>0.05). Also, antibody titres during incubation and serum of day old chicks showed no significant difference (P>0.05). Hence, evaluation of egg yolk antibodies is a valuable tool for estimation of antibody levels in serum of breeders and their chicks. Results of NDV EID50 test showed significant difference between eggs with NDV antibodies and SPF eggs (P<0.05). But, this comparison about AIV was non-significant (P>0.05). Hence, it is better to use SPF eggs for determination of EID50 of NDV.

Escherichia coli is an opportunistic organism which can cause Colibacillosis syndromes (colisepticemia, pericarditis, perihepathitis, salpingitis and …). E.coli has four phylogenetic groups including A, B1, B2 and D. Phylotyping is an adequate method for surveying the dissipation type of the phylogenetic groups of E.coli isolates in different regions. The present study was conducted to determine the phylogenetic groups of E.coli in Zabol city. In order to determine the frequency of the phylogenetic groups of E.coli in Zabol, 144 broilers suspected of Colibacillosis were sampled and samples were transferred to laboratory in TSB. After culturing and applying some common biochemistry tests, a total number of 100 E.coli were isolated. DNA of all isolates was extracted by boiling method and phylogenetic groups were determined by triplex PCR procedure. In this study; 36 %, 27 %, 23 % and 14 % of 100 E.coli isolates belonged to B1, D, A and B2 phylogenetic groups; respectively. The present study concluded that almost all of E.coli samples which were collected from broilers suspected of Colibacillosis in Zabol belonged to B1 phylogenetic group.

Nowadays, antibacterial effects of medicinal plants are considered as an appropriate alternative of antibiotics. Therefore, the aim of the current study was in vitro determination of antimicrobial effects of caper (Capparis spinosa) against Salmonella typhmurium isolated from poultry. Ethanol extract of caper leaves was extracted using vacuum from the center (rotary) apparatus. Moreover, a total number of 12 S. typhmurium strains were isolated from poultry in Zabol. Minimum inhibitory concentration and minimum bactericidal concentration of different concentrations of plant extract were determined on bacteria using dilution in well method. Sensitivity of bacteria strains to antibiotics were evaluated using Kirby-Bauer disk diffusion standard test. Results of the current study showed that different strains of bacteria are resistant to Penicillin (100 %), Ampicillin (100 %), Tetracycline (16.6 %) and Amikacin (8.3 %). Furthermore, ethanol extracts of caper plant showed significant inhibitory effect on S. typhimurium. Results of the current study indicated that there is possibly of using ethanol extract of caper plant as a useful alternative beside usual antibiotics.