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This work aimed to evaluate phenotypically and genotypically the colistin susceptibility of 85 Salmonella Infantis strains isolated in Italy from the broiler production chain, and to apply a whole-genome approach for the determination of genes conferring antimicrobial resistance (AMR). All isolates were tested by the broth microdilution method to evaluate the colistin minimum inhibitory concentrations (MICs). A multiplex PCR was performed in all isolates for the screening of mcr-1, mcr-2, mcr-3 mcr-4, mcr-5 genes and whole-genome sequencing (WGS) of six S. Infantis was applied. Three out of 85 (3.5%) S. Infantis strains were colistin resistant (MIC values ranged from 4 to 8 mg/L) and mcr-1 positive. The mcr-1.1 and mcr-1.2 variants located on the IncX4 plasmid were detected in three different colistin-resistant isolates. The two allelic variants showed identical sequences. All six isolates harbored blaCTXM-1, aac(6′)-Iaa and gyrA/parC genes, mediating, respectively, beta-lactam, aminoglycoside and quinolone resistance. The pESI-megaplasmid carrying tet(A) (tetracycline resistance), dfrA1, (trimethoprim resistance) sul1, (sulfonamide resistance) and qacE (quaternary ammonium resistance) genes was found in all isolates. To our knowledge, this is the first report of the mcr-1.2 variant described in S. Infantis isolated from broilers chickens. Our results also showed a low prevalence of colistin- resistance, probably due to a reduction in colistin use in poultry. This might suggest an optimization of biosecurity control both on farms and in slaughterhouses.

This work aimed to evaluate the antimicrobial susceptibility of 87 Salmonella Infantis strains isolated in Italy from 2016 to 2019 along the food chain of broiler meat production and in humans and to determine the genetic profiles of the strains in order to establish a possible correlation with the antimicrobial pattern. All isolates were tested by the disk diffusion method to evaluate antimicrobial susceptibility toward sixteen antimicrobials, and the broth microdilution method was used to confirm extended spectrum β-lactamase (ESBL) production. PCR and pulsed field gel electrophoresis (PFGE) were applied to characterize ESBL-encoding and AmpC β-lactamase genes and to analyze the S. Infantis strains genetic profiles respectively. S. Infantis isolates showed high prevalence of resistance, in particular toward nalidixic acid (97.7%), tetracycline (96.5%), sulphamethoxazole/trimethoprim (91%) and cefepime (72.4%). The 80.5% of isolates were ESBL, cefotaxime-resistant, carrying the blaCTX-M1 gene. The most prevalent PFGE profile was XbaI.0126 (35.6%). The remaining strains had a genetic homology from 81% to 97% with the XbaI.0126 profile. The strains belonging to these profiles were isolated from different matrices collected along the broiler food chain independently on the year and from the region and there was no correlation between the PFGE profiles and resistance patterns. We found two ESBL-producing S. Infantis strains with the same XbaI.2621 profile isolated from humans and from poultry feces, not yet reported in Italy. Our findings confirmed the diffusion of ESBL-multi drug resistant (MDR) S. Infantis along the broiler food chain and in humans and underlined the importance of continuous monitoring to control and to reduce the prevalence of this bacterium, applying a global One Health approach.

Among oregano properties, its antioxidant and antibacterial effects are particularly interesting. Oregano is also able to induce a higher glycoconjugate production in gut, creating a physical barrier against microorganisms. This study evaluated the effects of adding an aqueous extract of oregano (OAE) to the diet of two homogenous groups of pigs during the finisher phase. The diets were as follows: control commercial diet (CTR group) and CTR diet supplemented (2 g/kg) with OAE (O group). Samples of ileum and caecum from the two groups were examined by conventional histochemistry to analyze complex carbohydrates and by immunohistochemistry to detect Bcl-2 Associate X protein (BAX), an indicator of oxidative stress. Glyco-histochemistry showed significant differences between the two groups. Immunohistochemistry revealed a lower presence of BAX in O group. The OAE supplementation improved the production of glycoconjugates, able to enhance in pig the protection of intestinal mucosa by means of direct and indirect defense actions. The reduced BAX immunostaining observed in O group may be an indicator of enhanced antioxidant action promoted by oregano. The results of this study can be used in further research to identify ways to improve endogenous defence ability, with the aim of reducing antibiotic use and preventing antimicrobial resistance.

The spread of resistant bacteria from livestock to the food industry promoted an increase of alternative poultry production systems, such as organic and antibiotic-free ones, based on the lack of antimicrobial use, except in cases in which welfare is compromised. We aimed to investigate the antibiotic susceptibility of commensal Escherichia coli isolated from organic, antibiotic-free, and conventional broiler farms and slaughterhouses toward several antimicrobials critically important for human health. To assess antimicrobial susceptibility, all E. coli isolates and extended spectrum beta-lactamase (ESBL) E. coli were analysed by the microdilution method. The prevalence of tigecycline, azithromycin and gentamicin E. coli-resistant strains was highest in organic samplings. Conversely, the lowest prevalence of resistant E. coli strains was observed for cefotaxime, ceftazidime and ciprofloxacin in organic systems, representing a significant protective factor compared to conventional systems. All E. coli strains were colistin-susceptible. Contamination of the external environment by drug-resistant bacteria could play a role in the presence of resistant strains detected in organic systems. Of interest is the highest prevalence of cephalosporin resistance of E. coli in conventional samplings, since they are not permitted in poultry. Our results suggest that monitoring of antibiotic resistance of the production chain may be helpful to detect “risks” inherent to different rearing systems.

The objectives of this work were to evaluate β-lactamase-mediated β-lactam resistance in Campylobacter coli and Campylobacter jejuni isolates obtained from broiler chickens, expression of the bla

As a result of public health concerns regarding antimicrobial resistance in animal-based food products, conventional poultry companies have turned to &lsquo, raised without antibiotics&rsquo, (ABF) and organic farming systems. In this work, we evaluated the influence of rearing systems on antimicrobial susceptibility in E. coli and extended-spectrum &beta, lactamase (ESLB) E. coli diffusion in conventional (C), organic (O) and antibiotic free (ABF) chicken samples collected from cloacal swabs and skin samples in slaughterhouse. The E. coli isolates from conventional (135), antibiotic-free (131) and organic (140) samples were submitted to the Kirby&ndash, Bauer method and ESBL E. coli were analyzed by the microdilution test. Conventional samples showed the highest number of strains resistant to ampicillin (89.6%, p &lt, 0.01), cefotaxime (43.7%, 0.01), nalidixic acid (57.8%, 0.01), ciprofloxacin (44.4%, 0.001), and trimethoprim/sulfamethoxazole (62.2%, 0.01), with patterns of multi-resistance to three (35.1%) and to four antimicrobials (31.3%), whereas most of the E. coli isolated from antibiotic-free and organic chicken samples revealed a co-resistance pattern (29.2% and 39%, respectively). The highest number of ESBL E. coli was observed in conventional, in both cloacal and skin samples and the lowest in organic (p &lt, 0.001). Our results are consistent with the effect of conventional farming practices on E. coli antimicrobial resistance and ESBL E. coli number, due to the use of antimicrobials and close contact with litter for most of the production cycle.

The objectives of this work were to evaluate β-lactamase-mediated β-lactam resistance in Campylobacter coli and Campylobacter jejuni isolates obtained from broiler chickens, expression of the blaOXA-61 gene in relation to β-lactamase production, and the possible association between blaOXA-61 gene expression and the action of inhibitors when combined with β-lactams. All strains were tested by disk diffusion and nitrocefin methods to assess antibiotic susceptibility and β-lactamase production, respectively. PCR and qPCR amplification were performed to evaluate qualitative and quantitative blaOXA-61 expression. Campylobacter spp. showed a high level of resistance to the most of antimicrobials tested. C. coli strains were ampicillin resistant and blaOXA-61 positive, and 59 out of 60 isolates were positive in the nitrocefin test. Twenty C. jejuni isolates were positive for blaOXA-61 and the nitrocefin test, although two isolates were ampicillin sensitive. Amoxicillin/clavulanic acid and ticarcillin/clavulanic acid do not seem to be active against C. coli, as 73.3 %, and 88.3 % of isolates were resistant to amoxicillin/clavulanic acid and ticarcillin/clavulanic acid, respectively. C. jejuni was not susceptible to amoxicillin/clavulanic acid, with 90 % of the strains showing resistance, whereas ticarcillin associated with clavulanic acid was significantly more efficient than ticarcillin alone (P < 0.01), with 90 % of the strains found to be susceptible. An association between blaOXA-61 expression and amoxicillin/clavulanic acid and ticarcillin/clavulanic acid resistance (P = 0.0001) was seen in C. coli, as well as in C. jejuni for ampicillin/sulbactam (P = 0.0001). Our results suggest that the clavulanic acid only shows an inhibitory effect on C. jejuni when combined with ticarcillin and that the inhibitors action is lower if the blaOXA-61 gene is highly expressed.

Biofilm-forming ability is increasingly being recognized as an important virulence factor in several Staphylococcus species. This study evaluated the biofilm-forming ability of sixty canine derived clinical isolates of S. pseudintermedius, using three phenotypic methods, microtiter plate test (MtP), Congo red agar method (CRA) and tube adherence test, and the presence and impact of biofilm-associated genes (icaA and icaD). The results showed that icaA and icaD genes were detected concomitantly in 55 (91.7%) of 60 isolates. A majority (88.3%) of the strains screened had matching results by the tube adherence test, MtP and PCR analysis. Better agreement (95%) was found between the PCR-based analysis and the CRA. Results of the icaA and icaD gene PCRs showed good agreement with CRA results, with a kappa of 0.7. Comparing the phenotypic methods, the statistical analysis showed that the agreement among the phenotypical tests using categorical data was generally good. Considering two classes (biofilm producer and biofilm non-producer), the percentage of matching results between the CRA method and the tube adherence test and between the CRA method and the MtP was 93.3%. A concordance of 100% was revealed between the MtP and the tube adherence test. The results indicate a high prevalence of the ica genes within S. pseudintermedius isolates, and their presence is associated with in vitro formation of a biofilm. A combination of phenotypic and genotypic tests is recommended for investigating biofilm formation in S. pseudintermedius.

Ascending infections of equine uterus frequently result in placentitis and abortions; most of these infections are bacterial and are less commonly due to fungi. This report describes an abortion case in an Arab mare due to Candida guilliermondii that was diagnosed via cytological, histological, cultural and biomolecular assays. The histological lesions found were severe necrotizing placentitis associated with fetal pneumonia. To our knowledge this is the first case of C. guilliermondii abortion reported in equine species.

This is the first paper describing the cloning of pigeon IFN-γ gene (PiIFN-γ) and the analysis of the in vitro expressed recombinant protein. The PiIFN-γ gene was identified by RT-PCR as a 498 bp, fragment coding for a precursor protein of 165 amino acids instead of 164 amino acids, as observed in the other avian species. The recombinant protein was expressed in vitro by an eukaryotic system and the biological properties of the cytokine were tested using a chicken macrophage cell line. The high degree of amino acid and nucleotide identity, shared with the ChIFN-γ, and the fact that the pigeon protein was functional on chicken cells, indicates a cross-reactivity between pigeon and chicken IFN-γ. The detection of the PiIFN-γ could represent an useful instrument in understanding the role played by this cytokine in immune response related to vaccinations and infectious diseases in the pigeon.

The progression of some parameters of natural immunity in meat turkey reared outdoors was investigated. The levels of the haemolytic complement were lower than those obtained in commercial turkeys and in turkeys reared in a controlled environment during one of our previous investigations. The weather conditions could have influenced the trend of the haemolytic complement in turkeys selected for high meat production and kept outside, underlining the possible importance of the rearing system.

The present study was conducted to evaluate in field the efficacy of an additive (SOP® C POULTRY), as an agent for the control of micro-organisms in broiler litter. The Total aerobic Microbial Count (TMC), Staphylococcus species (spp.), Coliforms, and Salmonella spp. in broiler litter samples of both the Houses, 2 (H2) and 3 (H3), were determined, and also at the end of each cycle the mortality rate was recorded. The results showed significant reduction of all the microbial counts: P= 0.0078 (CMT), 0,0021 (Staphylococcus spp.) and 0.0541 (Coliforms), and mortality (P= 0.00106) in treated litter samples H2 and the control H3.

In recent years, there has been increasing evidence of the potential pathogenic significance of equine gammaherpesviruses in the horse. In humans, cattle and mice, gammaherpesviruses have already been associated with uterine infection. The aim of the present study was to investigate the presence of gammaherpesviruses in uterine flushings of mares with reproductive problems and to evaluate if there was a possible statistical association with clinical and laboratory findings in these cases. A total of 80 uterine flushings were collected from 61 mares with different reproductive problems and these were tested for equine herpesviruses (EHV) 1–5 by PCR. In the case of each mare in the study, the age, history of infertility, presence of anatomical defects in the reproductive tract, presence of systemic or local disease at time of sampling, phase in the oestrous cycle, post-partum interval, nature of uterine lavage performed (low versus large volume lavage), cytological and bacteriological examination results from the uterine flushing, and PCR herpesvirus results were recorded. Univariate analysis and multivariable logistic regression models were used to identify possible statistical associations and risk factors. Nine out of 61 mares (14.7%) had EHV-5 DNA in their uterine flushings. Co-infections with EHV-1 and EHV-2 were present in two cases. Of all the variables analyzed, only the cytological examination findings were associated with EHV-5 PCR positive results, both on univariate and multivariable analysis, especially in cases with an inflammation score of 3. It is postulated that presence of EHV-5 infection in the non-pregnant uterus may have a role to play in reproductive dysfunction and have a negative consequence on the pregnant uterus. Additional studies involving both healthy mares and mares with reproductive problems need to be performed, however, to elucidate whatever role equine gammaherpesviruses may play in the reproductive tract. This would be very worthwhile, since reproductive problems can have a significant impact on the equine breeding industry. Gaining a greater understanding of its causes could lead to new approaches for prevention and treatment.

The aim of this study was to evaluate the possible differences in the intestinal microflora composition among the different rearing systems (conventional vs organic) and the Salmonella diffusion using bacteriological techniques. The results showed that the differences between the two groups at the same age, expressed by the bacterial count, are not conclusive in showing an influence of the rearing systems. Salmonella Hadar was isolated once in caeca of conventional and once in caeca of organic ones. Though the results are preliminary and referred to a well defined geographic area in Central Italy, Salmonella detection does not seem to be common in conventional and organic chicken farms.

This paper describes a case of an unusual recovery of adult Ascaridia galli in hen’s egg. Several data are available on this occurrence but it appears to be the first case described in Italy. The worm was identified as an adult female, 6.8 cm in length, with three trilobed lips, cervical narrow alae, oesophagus club-shaped without posterior bulb, vulva near the middle of body, with gravid uteri containing a large number of eggs. The presence of Ascaridia galli in hen’s eggs cannot be considered as hazard for public health but may be cause of a potential consumer complaint. Moreover it is a sign of presence of ascaridiosis, parasitosis that still produces economic losses in modern poultry production system.

This paper reviews the composition of colostrum and the potential preventive and therapeutic use of this "first milk" for treating various gastrointestinal disorders in humans. Colostrum is a complex biological liquid that is richer in antimicrobial peptides, immune-regulating compounds and growth factors than the subsequent mature milk. The main functions of colostrum are to provide essential nutritional components, strengthen the natural defense system, modulate immune response, balance intestinal microbiota and enhance the growth and repair of several tissues. Several studies and clinical trials carried out both in vitro and in vivo on humans and animals suggest the clinical benefits of bovine colostrum (BC) supplementation in gastro-intestinal diseases. Despite the encouraging results, further well-designed studies are required in order to confirm these effects, the dose and duration of treatment. Colostrum is safe since there are no contraindications regarding high dose levels and few side effects of clinical relevance have been reported. In conclusion, in the near future, colostrum-based supplements may play a complementary role to synthetic drugs in the prevention and treatment of various gastrointestinal disorders.