Occurrence and antimicrobial susceptibility of Campylobacter spp. on fresh and refrigerated chicken meat products in Central Italy.

This study investigated the presence and the level of Campylobacter spp. contamination in 41 thigh samples (with skin) and 37 skinless breast samples collected at the end of slaughter (T1) and after 10 day period at refrigeration temperature (4°C) (T2), corresponding to their commercial shelf life. The isolates were phenotypically classified as Campylobacter spp. and successively identified by conventional multiplex PCR. The antimicrobial susceptibility of the isolates from fresh thigh and breast samples was also determined via the microdilution method (MIC) in Eucamp microtitre plates with known scalar concentrations of: gentamicin (GEN), streptomycin (ST), ciprofloxacin (CIP), tetracycline (TET), erythromycin (ERY), and nalidixic acid (NA). A greater percentage of positivity for Campylobacter spp. (P < 0.001) was observed in thighs and C.jejuni appeared to be the most common species identified at this level (P < 0.001) followed from its association with C.coli. There was a global reduction of Campylobacter spp. in both thigh and breast samples at T2 (P < 0.001) showing that the refrigeration was able to reduce Campylobacter count. The prevalence of resistance to CIP, TET, NA, and ERY was evidenced for C.jejuni and C. coli. The co (TET-NA, CIP-NA) and multiple resistant (CIP-TET-NA, CIP-TET- NA-ERY) isolates came from the thigh products. It should be highlighted the presence of Campylobacter spp. isolates resistant to ST occurred in breast samples, responsible for the ST-CIP co-resistance and ST-CIP-TE multi-resistance profiles, higher in breast than in thigh products (P > 0.001). The presence of Campylobacter isolates resistant to ST can be further investigated since it is used for therapeutic treatment of several bacterial diseases in humans.

Genetic diversity and antimicrobial resistance profiles of Campylobacter coli and Campylobacter jejuni isolated from broiler chicken in farms and at time of slaughter in central Italy.

AIMS: Genetic diversity and antimicrobial resistance of Campylobacter coli and Campylobacter jejuni were investigated along the broiler chicken production chain in central Italy. METHODS AND RESULTS: Campylobacter sp. isolated from cloacal swabs in farms (n = 116) and from the neck skin of chilled and eviscerated carcasses at slaughter (n = 24) were identified as C. coli (n = 99) and C. jejuni (n = 41) by multiplex PCR. Characterization by single amplified fragment length polymorphism (s-AFLP) revealed a specific genotype of Campylobacter for each farm. Minimal inhibitory concentration showed high prevalence of fluoroquinolones (70%), tetracycline (70%) and erythromycin (30%) resistance among C. coli isolates. Campylobacter jejuni isolates showed lower prevalence of fluoroquinolone (39%) and tetracycline (10%) resistance, and all isolates were susceptible to erythromycin. The S-AFLP types of the C. coli and C. jejuni isolates were associated with their antimicrobial resistance profiles (P < 0·001). CONCLUSIONS: The genetic diversity detected in Campylobacter isolates suggested that a specific genotype was harboured in each farm. A considerable number of C. coli isolates were resistant to erythromycin. SIGNIFICANCE AND IMPACT OF THE STUDY: Campylobacter coli was detected more frequently than C. jejuni in contrast to common findings for poultry. The high prevalence of 30% resistance to erythromycin in C. coli strains isolated from poultry is worrisome, as this is the first antibiotic of choice to treat human campylobacteriosis.

Gut complex carbohydrates and intestinal microflora in broiler chickens fed with oregano (Origanum vulgare L.) aqueous extract and vitamin E.

One hundred and seventy one-day-old female broiler chicks were randomly divided into three groups fed with different dietary treatments: basal control diet (C); C supplemented (2 g/kg) with an oregano aqueous extract (O); C supplemented (150 mg/kg) with vitamin E (E). Growth performance was evaluated at 21 (T1) and 42 days (T2). On the same days, morphological, histochemical and microbiological analyses were performed. The O group showed the highest (p < 0.01) body weight at T1, while no differences were observed at T2. Light microscopic observation and conventional histochemistry showed no differences with regard to the two sampling times, whereas significant differences emerged among the treatments. The O treatment generally enhanced goblet cell reactivity more than both the C and E treatments. Coliform count was lower in the ileum tract of the O group at both T1 and T2 (p < 0.05) and increased with age in all groups. Escherichia coli showed the lowest values in the caecum of the O group (p < 0.001) at both sampling times. Enterococci, lactobacilli and staphylococci populations showed no differences among the different experimental groups in the caecum. In the ileum, the O group did not exhibit the sharp decline (p < 0.001) in the lactic acid bacteria population observed in the other two experimental groups. In conclusion, oregano aqueous extract supplementation seemed to elicit the best response among treatments, enabling better growth performance, enhancing both the quantity and quality of glycoconjugates involved in indirect defence actions and significantly reducing both the coliform and E. coli counts.

Probiotic mixture supplementation in the preventive management of trinitrobenzenesulfonic acid-induced inflammation in a murine model.

Inflammatory bowel diseases (IBD) are characterized by inflammatory conditions of the intestine. Probiotic bacteria (PB) can have beneficial effects in several gastrointestinal disorders. The objectives of this study were: (i) to provide an acute experimental IBD model induced by 2,4,6-trinitrobenzenesulfonic acid (TNBS) in CD-1 mice, and (ii) to assess the preventive effects of Citogenex (Lactobacillus casei and Bifidobacterum lactis) supplementation on intestinal tissues and microbiota. Mice were inoculated intrarectally with saline, ethanol or different TNBS solutions. 1%TNBS induced clinical signs of colitis (P less than 0.01) and histological damage (P less than 0.01). Based on these results, mice were pre-treated with Citogenex or saline for 1, 2 or 3 weeks before 1%TNBS treatment. Probiotic pre-treatment determined a reduction of clinical signs (P less than 0.05), histological alterations of colitis (P less than 0.05) and increased beneficial bacteria (P less than 0.05). This study confirms that TNBS-induced colitis in CD-1 mice is useful for studying the mechanisms involved in IBD pathogenesis, and pre-treatment with Citogenex prevents the intestinal damage induced by TNBS.

Microbiological and parasitological survey of zoonotic agents in apparently healthy feral pigeons.

Microbiological and parasitological investigation was carried out on a colony of feral pigeons, located in a green area near the main hospital of a Central Italy city. One hundred pigeons were submitted to clinical examination. Cloacal swabs, grouped in pool of 4 samples, were analyzed to detect the presence of Coxiella burnetii, Chlamydia psittaci, Chlamydophila spp. using a biomolecular procedure, while individual cloacal samples were examined for Salmonella spp., Campylobacter spp., and yeasts by means of a specific culture media. An ELISA test was used to determine the presence of Giardia spp., and Cryptosporidium spp. coproantigens. Individual serological samples were also tested with the modified agglutination test (MAT) in order to detect antibodies against Toxoplasma gondii. The pigeons did not show any clinical signs. The cloacal pools proved to be negative for C. burnetii DNA while three pools were positive for C. psittaci or Chlamydophila spp. DNAs. Salmonella spp. was not detected. C. jejuni and C. coli were found in 13% and 4% of the samples, respectively. No Giardia spp. and Cryptosporidium spp. were detected. Thirty-three out of 100 samples (33%) were positive for yeast colonies. The seroprevalence for T. gondii was 8%. Although with moderate incidence, potentially zoonotic agents were present thus highlighting the need for sanitary surveillance on feral pigeon colonies.

Effects of two different probiotics on microflora, morphology, and morphometry of gut in organic laying hens.

The current study investigated the effects of Lactobacillus acidophilus and Bacillus subtilis, used as probiotics, on the microflora, morphology, and morphometry of the gut in organic laying hens. The birds (180 Hy-Line laying hens) were divided into 3 homogenous groups and received a pre-deposition diet from 16 to 20 wk of age and a deposition diet for the remaining 7 months of the experiment. The control group ( CTR: ) was fed a corn-soybean cake-based diet, the second group ( L: ) received the same diet supplemented with 0.1% of L. acidophilus while in the third group ( B: ) the basal diet was supplemented with 0.05% of B. subtilis At 18 wk of age ( T1: ) and at 5 ( T2: ) and 7 months ( T3: ) from the beginning of deposition, 9 subjects per group were humanely killed for microbiological, morphological and morphometric analyses of the intestinal tract. The 2 probiotic-supplemented diets increased Lactobacillus spp. and Bifidobacterium spp. counts compared with the CTR diet. The lowest viable counts of E. coli, coliforms and staphylococci were observed in the L group (P < 0.001). Clostridium spp. decreased (P < 0.001) in both L and B subjects. The probiotic supplementation appeared to affect the intestinal microbial population, promoting the presence of beneficial bacteria such as Lactobacillus spp. and Bifidobacterium spp. and reducing potential harmful bacteria such as E. coli, clostridia and staphylococci. Morphological and morphometric analyses did not reveal substantial differences among groups. At T3, the plasma cell infiltrate in the villi of the CTR hens was more severe than that observed in the L and B groups (P = 0.009).

Rhodococcus equi pneumonia in foals: an assessment of the early diagnostic value of serum amyloid A and plasma fibrinogen concentrations in equine clinical practice.

Early diagnosis and prevention of Rhodococcus equi pneumonia in foals represent important goals for equine clinicians. Recent protocols for diagnosis and treatment of Rhodococcosis in foals typically rely on a multimodal approach based on sonographic evidence suggestive of pyogranulomas, sonographic abscess scores and laboratory findings including plasma fibrinogen concentrations, blood biochemistry testing and platelet and leukocyte counts. The aim of this study was to assess the utility of weekly testing of serum amyloid A (SAA) and plasma fibrinogen concentrations in foals to achieve early diagnosis of R. equi pneumonia prior to the onset of clinical signs. This testing was used to simulate a clinically practical screening procedure and compared with thoracic ultrasonography performed in parallel. The present study suggests that SAA does not represent a reliable early marker of Rhodococcosis when plasma concentrations are tested weekly. However, when clinical signs of R. equi pneumonia are present, SAA concentrations may allow clinicians to obtain 'real-time' indications concerning both the progress of infection and the effectiveness of therapy. This study raises the possibility that plasma fibrinogen monitoring starting at 1 week of age and repeated on a weekly basis, could serve as a screening test allowing clinicians to identify foals as suspected of R. equi infection. Future investigations regarding both physiological plasma fibrinogen concentrations in foals as well as fibrinogen kinetics in foals affected with R. equi pneumonia, including the establishment of appropriate reference intervals for the test method employed in this study, will be necessary in order to clarify this possibility.

Insertion sequence IS256 in canine pyoderma isolates of Staphylococcus pseudintermedius associated with antibiotic resistance.

Staphylococcus pseudintermedius is the most frequent staphylococcal species isolated from canine pyoderma. The control of S. pseudintermedius infection is often difficult due to the expanded antimicrobial resistance phenotypes. Antibiotic resistance in staphylococcal pathogens is often associated to mobile genetic elements such as the insertion sequence IS256 that was first described as a part of the transposon Tn4001, which confers aminoglycoside resistance in Staphylococcus aureus and in Staphylococcus epidermidis. In this study a collection of 70 S. pseudintermedius isolates from canine pyoderma was used to investigate antimicrobial susceptibility to 15 antibiotics and the presence of IS256, not revealed in S. pseudintermedius yet. Antibiotic resistance profiling demonstrated that all S. pseudintermedius isolates had a multi-drug resistance phenotype, exhibiting simultaneous resistance to at least five antibiotics; indeed methicillin resistant S. pseudintermedius isolates were simultaneously resistant to at least nine antibiotics and all were also gentamicin resistant. PCR analyses revealed the presence of IS256 in 43/70 S. pseudintemedius isolates. The association between the presence of IS256 and the resistance was particularly significant for certain antibiotics: cefovecin, amikacin, gentamicin and oxacillin (χ(2)p-value<0.05). However, there was a striking result in frequency of strains resistant to gentamicin and oxacillin, suggesting a specific association between the presence of the IS256 element and the determinants for the resistance to these antibiotics. To the best of our knowledge, this is the first report showing the detection of IS256 in S. pseudintermedius isolates and its association with antibiotic resistance. Our findings suggest that S. pseudintermedius may acquire antibiotic resistance genes through mobile genetic elements which may play a predominant role in the dissemination of multi-drug resistance.

Influence of different rearing systems on natural immune parameters in broiler turkeys.

The aim of this study was to determine serological values of lysozyme, hemolytic complement levels (alternative pathway), and bactericidal activity of serum in turkeys kept in different rearing systems (industrial, backyard, and experimental). Results showed that the values for serum bactericidal activity and hemolytic complement levels increased with age, and their values were higher in experimental and in industrial turkeys than in turkeys reared in backyard. Lysozyme concentration showed a similar pattern; its value was higher in the industrial and experimental groups than in the backyard group. Data obtained suggest that rearing system can have an influence on the natural immune parameters considered; experimental and industrial groups showed a similar trend, differentiated from that observed in the backyard group. In the backyard group, the values observed may suggest that hybrid turkeys, selected for high production, have difficulty with being reared outside where predators (foxes and weasels) and weather conditions could be responsible for a stress situation.

Isolation and characterization of ß-haemolytic-Streptococci from endometritis in mares.

The objective of this manuscript was to validate published PCR-based methods for detection of ß-haemolytic Streptococci by comparison with established bacteriological techniques using 85 clinical isolates recovered from uterine swabs of mares with clinical signs of endometritis and to determine the distribution of SeeL/SeeM and SzeL/SzeM superantigens in isolates of Streptococcus equi subsp. equi (S. equi) and S. equi subsp. zooepidemicus (S. zooepidemicus). The conventional bacteriological techniques showed the vast majority of these isolates (78) were S. zooepidemicus with just 5 Streptococcus dysgalactiae subsp. equisimilis (S. equisimilis) and 2 S. equi strains detected. The PCR analyses confirmed the bacteriological results demonstrating the reliability of the 16S rRNA PCR assay for detecting Streptococci, the multiplex PCR for differentiating between S. zooepidemicus, and S. equi, and PCR assays based on streptokinase genes for identification of S. equisimilis. PCRs for genes encoding superantigens revealed seeL and seeM specific amplicons with size of approximately 800 and 810 bp respectively for the S. equi strains and for 2 S. zooepidemicus strains. To our knowledge, this is the first report of szeL and szeM possession by S. zooepidemicus isolates derived from endometritis in mares.

Development of a polymerase chain reaction-based in vivo method in the diagnosis of subclinical pigeon circovirus infection.

This paper describes a polymerase chain reaction (PCR)-based method performed on blood samples and intestinal content to detect subclinical pigeon circovirus (PiCV) infection in live pigeons. In addition, two sets of primers (primer set 1 and 2), designed in two different regions of the viral genome, were used to provide evidence of possible differences in PCR responses. Blood and intestinal content samples were randomly collected from a total of 50 apparently healthy meat pigeons, aged 1 to 5 wk, which came from central Italy. Samples of primary lymphoid organs were also collected. Results showed a high level of PiCV infection, although clinical signs were not present. The results obtained with the two sets of primers showed that primer set 2 was able to detect a higher number of PCR-positive pigeons (45 of 50 pigeons) than primer set 1 (11 of 50 pigeons). In both cases an increase in positive results with pigeon age indicates that the major direction of transmission is likely horizontal. In these circumstances feces can play an important epidemiologic role, as supported by the consistent circovirus detection in intestinal content. The high sensitivity of this PCR test, which is able to detect very low amounts of viral DNA (5.5 x 10(-3) fg of plasmid containing the cloned PiCV genome), makes it suitable for possible application as an epidemiologic tool for identifying virus carriers for subsequent removal from lofts.