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1.
The aim of this study was to perform the identification and molecular characterization of Arcobacter cryaerophilus and Arcobacter butzleri isolated from caiman (Caiman yacare), kept at a production farm, in Brazil. Forty fecal samples were analyzed. After isolation and identification, 21/40 strains of A. butzleri and 19/40 strains of A. cryaerophilus were subjected to PCR for potential virulence gene detection. The results of the PCR showed 38/40 strains positive for the cadF, cj1349, ciaB, and tlyA genes, 39/40 strains positive for the pldA gene, and 40/40 strains positive for the mviN gene. None of the strains presented the irgA gene. Hemagglutinin (hecA gene) and hemolysin (hecB) genes were detected in 21/40 and 16/40 strains, respectively. The SE-AFLP showed a great genetic diversity, but some clonally groups were disseminated in various tanks. These data reveal that the strains presented the same virulence traits described from Arcobacter isolated from food-borne disease in humans.  相似文献   

2.

Background

Identifying the aetiological agent of atypical pneumonia in human can sometimes be a tedious process, especially in cases where Mycoplasma pneumoniae, Legionella species and Chlamydia pneumoniae are ruled out. In such cases, a correct anamnesis of the patient is basic to clarify which pathogens might have produced the infection. For this reason, health professionals including veterinarians and laboratory personnel working with zoonotic pathogens should keep their doctors informed.

Case presentation

A human case of atypical pneumonia linked to Chlamydia abortus is reported. A 47-year-old male, a veterinarian researcher into chlamydiae, developed respiratory symptoms, breathing problems and high fever. Serological analyses ruled out the involvement of several respiratory pathogens, such as M. pneumoniae, Legionella pneumophila, Rickettsia conorii and C. pneumoniae, and Chlamydia abortus was identified as the possible aetiological agent of the infection. The isolation of C. abortus from the patient’s sputum and subsequent molecular analysis confirmed the presence of this microorganism.

Conclusion

As far as we know, although C. abortus has not been previously described as capable of causing pneumonia in humans, this is the first reported case of atypical pneumonia in which C. abortus is thought to have played an aetiological role.
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3.
Salmonellosis is a major bacterial disease causing huge economic losses in the poultry industry worldwide. This study was carried out to determine the period prevalence and antimicrobial susceptibility of Salmonella enterica in Japanese quails in Abeokuta, Nigeria. Four hundred cloacal swabs of quail birds were collected from 4 locations within Abeokuta. Salmonella was isolated from the samples using conventional methods for selective isolation of Salmonella and biochemical identification. Isolates were confirmed by polymerase chain reaction assays for the amplification and detection of Salmonella-associated virulence genes (invA and stn) using specific primers. Antimicrobial susceptibility testing was done using the Kirby-Bauer disk diffusion method. In all, Salmonella was isolated from 14 (3.5%) cloacal swabs. All 14 isolates possessed invA and stn genes. The Salmonella isolates showed resistance to tetracycline (100%), doxycycline (100%), ampicillin (100%), sulphamethoxazole (92.9%), nalidixic acid (85.8%), ceftazidime (78.6%), neomycin (64.3%), streptomycin (50%) and gentamycin (28.6%) but all the isolates were susceptible to ciprofloxacin. The isolates were resistant to at least three antimicrobials indicating multidrug resistance. The results concluded that Japanese quails harbour multidrug-resistant Salmonella which could be transmitted to humans through consumption of contaminated food or by direct and indirect contact with the carrier birds. Antimicrobial resistance could be due to overdependence on antimicrobials. Ciprofloxacin could be considered in the treatment of zoonotic Salmonellosis in humans.  相似文献   

4.
Anaplasma marginale and Babesia bigemina are important tick-borne pathogens of cattle. A cross-sectional survey was undertaken to determine the seroprevalence of A. marginale and B. bigemina infections and identify associated risk factors on traditional smallholder farms in Machakos County, Kenya. A total of 421 cattle from 127 farms from four divisions in the county were sampled and visited between September and November 2007. The farms were selected by a proportional allocation approach based on the number of farms in the four divisions previously selected by stratified random sampling method. Information on animal and individual farm management variables was obtained using standardized questionnaires. Prevalence of serum antibodies due to A. marginale and B. bigemina pathogens was determined using the enzyme-linked immunosorbent assay (ELISA) technique. The relationship between the seropositivity and associated risk factors was assessed by multivariable analyses using standard logistic regression models. The overall estimation (and their 95% confidence intervals) of A. marginale and B. bigemina seropositivity at the animal level was 53.4% (48.5%, 58.2%) and 40.6% (35.8%, 45.4%), respectively. Two variables, “animal age” and “administrative division,” were significantly associated with the A. marginale seroresponse. Three variables, “animal age” “grazing system” and “administrative division” were significantly associated with the B. bigemina seroresponse. These findings suggest possible indicators of existence of endemic instability for the two infections. The study identifies characterization of environmental suitability for the vectors and how they interact with grazing systems to cause the infections as an area for further studies, for improved understanding of the infections and in designing disease control programs.  相似文献   

5.
The genus Brucella causes significant economic losses due to infertility, abortion, stillbirth or weak calves, and neonatal mortality in livestock. Brucellosis is still a zoonosis of public health importance worldwide. The study was aimed to optimize and evaluate PCR assays used for the diagnosis of Brucella infections. For this aim, several primers and PCR protocols were performed and compared with Brucella cultures and biological material inoculated with Brucella. In PCR assays, genus- or species-specific oligonucleotide primers derived from 16S rRNA sequences (F4/R2, Ba148/928, IS711, BruP6-P7) and OMPs (JPF/JPR, 31ter/sd) of Brucella were used. All primers except for BruP6-P7 detected the DNA from reference Brucella strains and field isolates. In spiked blood, milk, and semen samples, F4-R2 primer-oriented PCR assays detected minimal numbers of Brucella. In spiked serum and fetal stomach content, Ba148/928 primer-oriented PCR assays detected minimal numbers of Brucella. Field samples collected from sheep and cattle were examined by bacteriological methods and optimized PCR assays. Overall, sensitivity of PCR assays was found superior to conventional bacteriological isolation. Brucella DNA was detected in 35.1, 1.1, 24.8, 5.0, and 8.0% of aborted fetus, blood, milk, semen, and serum samples by PCR assays, respectively. In conclusion, PCR assay in optimized conditions was found to be valuable in sensitive and specific detection of Brucella infections of animals.  相似文献   

6.
Mycobacterium avium subsp. paratuberculosis (MAP) causes Johne’s disease, a chronic enteritis in cattle and other domestic and wild ruminants. The presence of MAP in tissues other than intestines and associated lymph nodes, such as meat and liver, is a potential public health concern. In the present study, the relationship between the results of rapid diagnostic tests of the Johne’s disease, such as serum ELISA, rectal scraping PCR, and acid-fast staining, and the presence of MAP in liver was evaluated. Blood, liver, and rectal scraping samples were collected from 200 slaughtered cattle with unknown Johne’s disease status. ELISA was performed to determine the MAP antibody activity in the serum. Acid-fast staining was performed on rectal scraping samples, and PCR was performed on rectal scraping and liver samples. PCR-positive liver samples were used for mycobacterial culture. Overall, the results of this study demonstrated that MAP can be detected and cultured from liver of slaughtered cattle and rapid diagnostic tests of Johne’s disease have limited value in detecting cattle with MAP infection in liver. These findings show that the presence of MAP in liver tissue may occur in cows with negative results for rapid diagnostic tests and vice versa. Hence, liver might represent another possible risk of human exposure to MAP. Given concerns about a potential zoonotic role for MAP, these results show the necessity to find new methods for detecting cattle with MAP disseminated infection.  相似文献   

7.
8.
Anticoccidial effects of Aloe secundiflora crude leaf extract was tested in broiler chickens following oral infection with Eimeria tenella. Sixty 22-day-old birds were divided into six groups of ten birds each. Three treatment groups A, B, and C were fed with the extract (100, 250, and 500 mg/day, respectively) mixed in feed for 10 days, and three control groups: group D (drug control) administered 300 mg/l of sulfachloropyrazine sodium soluble powder in drinking water for 5 days, group E (infected/non-medicated positive control), and group F (uninfected/non-medicated negative control). Except for group F, all groups were orally inoculated with 75,000 sporulated oocysts of E. tenella. The effects of the extract on E. tenella infection were evaluated by severity of bloody diarrhea, body weight (BW) gain, oocyst output, and lesion score. No bird in the treated groups died of coccidiosis, and severity of bloody diarrhea was milder than in the positive control group. BW gains in the treated groups were significantly higher than in group E (p < 0.05). The lesion scores of the treated groups were significantly lower than that of group E. Oocyst output in groups A, B, and C were 11.23, 8.24, and 6.82 × 106, respectively. As compared with the negative control group (12.84 × 106), the reductions in oocyst production were 12.54, 35.83, and 46.88%, respectively. Oocyst output significantly reduced with an increase in Aloe dosage. The findings of this study suggest that Aloe secundiflora extract presents an alternative anticoccidial agent for the control of avian coccidiosis.  相似文献   

9.
Dichelobacter nodosus is the principal cause of ovine footrot and strain virulence is an important factor in disease severity. Therefore, detection and virulence determination of D. nodosus is important for proper diagnosis of the disease. Today this is possible by real-time PCR analysis. Analysis of large numbers of samples is costly and laborious; therefore, pooling of individual samples is common in surveillance programs. However, pooling can reduce the sensitivity of the method. The aim of this study was to develop a pooling method for real-time PCR analysis that would allow sensitive detection and simultaneous virulence determination of D. nodosus. A total of 225 sheep from 17 flocks were sampled using ESwabs within the Swedish Footrot Control Program in 2014. Samples were first analysed individually and then in pools of five by real-time PCR assays targeting the 16S rRNA and aprV2/B2 genes of D. nodosus. Each pool consisted of four negative and one positive D. nodosus samples with varying amounts of the bacterium. In the individual analysis, 61 (27.1%) samples were positive in the 16S rRNA and the aprV2/B2 PCR assays and 164 (72.9%) samples were negative. All samples positive in the aprV2/B2 PCR-assay were of aprB2 variant. The pooled analysis showed that all 41 pools were also positive for D. nodosus 16S rRNA and the aprB2 variant. The diagnostic sensitivity for pooled and individual samples was therefore similar. Our method includes concentration of the bacteria before DNA-extraction. This may account for the maintenance of diagnostic sensitivity. Diagnostic sensitivity in the real-time PCR assays of the pooled samples were comparable to the sensitivity obtained for individually analysed samples. Even sub-clinical infections were able to be detected in the pooled PCR samples which is important for control of the disease. This method may therefore be implemented in footrot control programs where it can replace analysis of individual samples.  相似文献   

10.
In this study, we investigated the dynamics of Mycoplasma hyopneumoniae infections in 66 pig farms, with different production systems (one-, two-, and three-site systems), and considered different risk factors. Serological assay was used to detect serum antibodies against M. hyopneumoniae and real time polymerase chain reaction (RT–PCR) was performed to detect M. hyopneumoniae DNA in tracheobronchial swabs. Results demonstrated that M. hyopneumoniae infection status was predominantly influenced by the age of the animals and the type of production system. Infection rates were higher in older animals and the prevalence was higher in the one- and two-site systems than in the three-site systems. Dynamics of infection by RT-PCR showed that earlier M. hyopneumoniae infection on one-site farms occurs earlier, while on two- and three-site farms occurs later but spreads faster, suggesting that contact between animals of different age favors the transmission.  相似文献   

11.
The aims of the present study were to determine (i) the profiles of phylogroup and (ii) the antimicrobial susceptibility of pathogenic Escherichia coli strains isolated from calves, and of Salmonella spp. strains isolated from calves and pigs in Minas Gerais State, Brazil. Sixty-one pathogenic E. coli strains and Salmonella spp. (n?=?24) strains isolated from fecal samples of calves and Salmonella spp. (n?=?39) strains previously isolated from fecal samples of growing/finishing pigs were tested. The minimum inhibitory concentration (MIC) using the agar dilution method was determined for nalidixic acid, amikacin, amoxicillin, ampicillin, cefoxitin, norfloxacin, gentamicin, tetracycline, and trimethoprim-sulfamethoxazole. All E. coli isolates were susceptible to amikacin. Tetracycline was the antimicrobial that presented the higher frequency of resistance among E. coli strains, followed by ampicillin, trimethoprim-sulfamethoxazole, amoxicillin, nalidixic acid, norfloxacin, gentamicin, and cefoxitin. E. coli (n?=?61) strains isolated from calves belonged to different phylogroup namely, phylogroup A (n?=?26), phylogroup B1 (n?=?31), phylogroup E (n?=?3), and phylogroup F (n?=?1). Phylogroups B2, C, and D were not identified among the E. coli in the present study. All Salmonella spp. (n?=?24) strains isolated from fecal samples of calves were susceptible to amikacin, amoxicillin, ampicillin, norfloxacin, gentamicin, tetracycline, and trimethoprim-sulfamethoxazole. Resistance to nalidixic acid and cefoxitin was detected in 16.66 and 8.33 % of the Salmonella spp. strains, respectively. Among the Salmonella spp. (n?=?39) strains isolated from fecal samples of pigs, the higher frequency of resistance was observed to tetracycline, followed by amoxicillin, gentamicin, ampicillin, trimethoprim-sulfamethoxazole, nalidixic acid, cefoxitin, and norfloxacin. All strains were susceptible to amikacin. Forty-eight (78.68 %) of the E. coli strains were classified as multidrug-resistant, whereas among Salmonella spp. strains, the percentage of multidrug resistance was 57.14 %, being all multidrug-resistant strains isolated from pigs (92.30 %). The results from the present study indicate a high frequency of antimicrobial resistance among pathogenic E. coli strains isolated from calves and Salmonella spp. strains isolated from pigs and a high rate of susceptibility to most antimicrobials tested among Salmonella spp. strains isolated from calves. Our study highlights the presence of multidrug-resistant strains of E. coli and Salmonella spp. isolated from food-producing animals in Minas Gerais, Brazil.  相似文献   

12.

Background and case presentation

A three year old, second lactation Holstein dairy cow presented to the Scottish Centre for Production Animal Health and Food Safety, Glasgow University Veterinary School in November 2014 with a history of post-calving vulval/vaginal bleeding nine days prior to presentation, followed by a sudden reduction in milk yield. Subsequent investigations resulted in a diagnosis of immune-mediated haemolytic anaemia secondary to infection with Mycoplasma wenyonii.

Conclusion

This report of a novel presentation of Mycoplasma wenyonii in a dairy cow illustrates the need to consider M.wenyonii as a potential differential diagnosis when a cow presents with anaemia and will discuss the potential implications of the condition at herd-level.
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13.

Objective

This study aims to investigate the immunoprotection of recombinant Eg.P29 (rEg.P29) vaccine and analyze the underlying mechanism in sheep.

Methods

Three groups of male sheep were immunized subcutaneously with rEg.P29 and PBS, Freund’s complete adjuvant as controls, respectively. After prime-boost vaccination, the sheep were challenged with encapsulated Echinococcus granulosus eggs. The percentage of protection in sheep was determined 36 weeks after the infection. Humoral immune response was analyzed for specific IgG, IgG1, IgG2, IgM and IgE levels. Moreover, cytokines including interferon (IFN)-γ, interleukin (IL)-2, IL-4,and IL-10 were also evaluated.

Results

Immunization with rEg.P29 induced protective immune responses up to 94.5 %, compared with immunoadjuvant group. The levels of specific IgG, IgG1, IgG2, and IgE as well as IFN-γ, IL-2, and IL-4 significantly increased after two immunizations (P < 0.05); however, the levels of IgM and IL-10 did not show difference.

Conclusion

rEg.P29 showed Immunoprotection and induced Th1 and Th2 immune responses; hence, rEg.P29 is a potential vaccine for E. granulosus infection.
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14.
A cross-sectional study was conducted to isolate and identify bacterial species from the respiratory tract of apparently healthy and pneumonic camels in Asayita and Dubti woredas in the Afar Region, Ethiopia. From a total of 74 lung tissue and 74 tracheal swab samples Staphylococcus aureus, 16.3%, Streptococcus equi subsp. equi, 13.0%, and Pasteurella multocida, 10.9%, were dominant isolates from pneumonic lungs; Escherichia coli, 12.7%, Proteus species, 10.9%, and Klebsiella pneumoniae, 9.1%, were the majority in the normal lungs. The majority of the isolates colonized both anatomical sites investigated. There was a statistically significant association between the health status of the camels as well as the anatomical site studied with the isolation rates of the major respiratory pathogens (p?<?0.05). Furthermore, the isolates were susceptible to norfloxacin, streptomycin, and gentamicin but resistant to ampicillin and tetracycline on in vitro test. Further studies on the pathogenicity of the major isolates are recommended.  相似文献   

15.
This study demonstrates the feasibility of using goldfish as an infection model to investigate the pathogenesis of Edwardsiella piscicida. Goldfish were found to be susceptible to acute E. piscicida-induced disease and died in a dose-dependent manner. E. piscicida was further shown to replicate rapidly in the head kidneys and livers of infected goldfish from 1 d post-injection, and bacteria numbers were significantly decreased 5 d post-injection. Immune responses were successfully induced in goldfish injected with E. piscicida strains and 60% of goldfish inoculated with an attenuated E. piscicida strain were found to survive subsequent injection with a pathogenic strain. The results of differential leukocyte count experiments suggested that leukocytes were immediately recruited as an innate immune response against the infection. Thus, this well-characterized goldfish species is a suitable infection model for studying E. piscicida pathogenesis, and might be applicable to research on other fish diseases.  相似文献   

16.
The prevalence of Trypanosoma evansi was investigated in 1,250 Nili-Ravi buffaloes of mixed age and sex by polymerase chain reaction (PCR) for the first time in Pakistan. DNA of the trypanosomes was isolated with TRIREAGENT®. The assay was employed using primers ESAG 6/7, specific for a 237-bp fragment from T. evansi genomic DNA. The samples were screened for the presence of T. evansi also by stained thin smear. Forty-four (3.5%) samples were positive by microscopy, while 97 (7.7%) samples were identified by PCR, indicating the high sensitivity of PCR for surveying the disease in epidemiological studies.  相似文献   

17.

Objective

This study evaluated the effects in vitro and in vivo of Agaricus blazei against Haemonchus contortus in sheep.

Methods

The in vitro efficacy of aqueous extract on egg hatching inhibition (EHI) was investigated and after 72 h incubation with varying concentrations the effects on, blastomeres, embryonated eggs, and first stage larvae (L1) were evaluated. Larval development inhibition (LDI) for dry powder and the aqueous extract were evaluated in fecal cultures of sheep infected with H. contortus. In vivo efficacy was determined by reduction in fecal egg count (FEC). Lambs were treated with powder A. blazei (11.4 g/kg pc) or trichlorfon, or were untreated and the possible toxicity of this fungus was monitored by plasmatic enzyme analysis.

Results

Concentrations equal to and higher than 3.62 mg/mL and of aqueous extract were 100% effective in the EHI test. In the LDI test, LC90 was estimated for 5.66 and 106.0 mg/g fecal culture for aqueous extract and powder, respectively. The mean FEC in lambs 14 days post-treatment with A. blazei powder was significantly lower than observed for the negative control, and the serum levels of aspartate transaminase and alanine transaminase were normal.

Conclusion

The fungi supplementation promotes, respectively, high and moderate anthelmintic efficacy with in vitro and in vivo tests, respectively, suggesting it as an alternative or complementary treatment for haemonchosis in sheep.
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18.
The objective of this study was to determine the effects of dietary supplementation of Nigella sativa L. seeds, Rosmarinus officinalis L. leaves and their combination on rumen metabolism, nutrient intake and digestibility, growth performance, immune response and blood metabolites in Dorper lambs. Twenty-four entire male Dorper lambs (18.68?±?0.6 kg, 4–5 months old) were randomly assigned to a concentrate mixture containing on a dry matter basis either, no supplement (control, T1), 1% R. officinalis leaves (T2), 1% N. sativa seeds (T3) or 1% R. officinalis leaves +1% N. sativa seeds (T4). The lambs had ad libitum access to urea-treated rice straw (UTRS) and were raised for 90 days. Supplemented lambs had greater (P?< 0.05) intake of DM and UTRS than the control lambs. The T4 lambs had lower (P?< 0.05) nutrient digestibility than those fed other treatments. Total and daily weight gain was greater (P?< 0.05) in T2 lambs than those fed other diets. The T3 and T4 lambs had greater (P?< 0.05) ruminal pH than the T1 and T2 lambs. Supplemented lambs had lower (P?<?0.05) ruminal total volatile fatty acids, acetate, propionate, NH3-N and C18:0 than the control lambs. The T4 lambs had lower (P?< 0.05) population of Fibrobacter succinogenes, Ruminococcus albus, methanogens and total protozoa compared with those fed other diets. Supplemented lambs had lower (P?< 0.05) neutrophils, basophils and serum urea and greater (P?<?0.05) serum IgA and IgG compared with the control lambs. The current results emphasised the variation in the efficacy of medicinal plants in ruminant nutrition.  相似文献   

19.
This study was made to investigate efficacy of eprinomectin pour-on against to Toxocara vitulorum in calves. In the study, 16 calves naturally infected with T. vitulorum were divided into two groups as treatment (eight calves) and control (eight calves). Eprinomectin (0.5 mg/kg, Eprinex®, Merial) was given to treatment group calves, and eggs per gramme were determined in the faeces on the day of pre-treatment and the second, third, fourth, fifth, sixth, 14th and 28th days of post-treatment. No side effects associated with nervous, respiratory and gastrointestinal systems were observed. In conclusion, eprinomectin was determined to be 100% effective against T. vitulorum. This is the first study to evaluate the efficacy of eprinomectin against a natural T. vitulorum infection in calves.  相似文献   

20.
The aim of this study was to evaluate the in vitro lethal effect of a hydroalcoholic extract (HAE) from Acacia cochliacantha leaf against three gastrointestinal nematodes species (Haemonchus contortus, H. placei and Cooperia punctata) of domestic ruminants. The HAE was assessed using five concentrations: 100, 125, 175, 150 and 200 mg/ml; 0.5% Ivermectin was used as a positive control and distilled water, as negative control. The data were normalized using the square root and analysed with a completely randomized design through ANOVA analysis using the general lineal model (GLM) of the SAS program. The HAE tannin content was determined through spectrophotometry (UV-visible) and the other major phenols, were identified by chromatographic processes. The results showed an in vitro larvicidal activity of the HAE against the three assessed nematode species with all assessed concentrations. A clear HAE increased concentration dependence effect was observed. The highest activity of the HAE was obtained at the highest concentration (close to 100%, P < 0.05). This result was similar to the one obtained with Ivermectin. On the other hand, the chemical analysis of HAE showed the presence of tannins, caffeoyls and coumaroyl derivates and quercetin as the main compounds. The results suggest that the HAE from this plant species possess in vitro anthelmintic properties. The identified compounds in this study would good candidates for further in vivo researches.  相似文献   

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