Quality Systems. A Thermodynamics-Related Interpretive Model

In the present paper, a Quality Systems Theory is presented. Certifiable Quality Systems are treated and interpreted in accordance with a Thermodynamics-based approach. Analysis is also conducted on the relationship between Quality Management Systems (QMSs) and systems theories. A measure of entropy is proposed for QMSs, including a virtual document entropy and an entropy linked to processes and organisation. QMSs are also interpreted in light of Cybernetics, and interrelations between Information Theory and quality are also highlighted. A measure for the information content of quality documents is proposed. Such parameters can be used as adequacy indices for QMSs. From the discussed approach, suggestions for organising QMSs are also derived. Further interpretive thermodynamic-based criteria for QMSs are also proposed. The work represents the first attempt to treat quality organisational systems according to a thermodynamics-related approach. At this stage, no data are available to compare statements in the paper

Clinical findings in sheep farms affected by recurrent bacterial mastitis

This study was aimed to investigate the relationships existing between clinical findings and bacterial entities isolated from milk of dairy sheep affected by mastitis. The influence of other parameters on the clinical picture, such as age, nutritional state, breeding conditions, and milking techniques, was also evaluated. All sheep belonged to flocks suffering from serious and repeated outbreaks of infectious mastitis. A total of 2198 Sarda dairy sheep were subjected to a detailed clinical examination, and at least one clinical sign of mastitis was detected in 1666 sheep (75%). Bacteriological examination of milk samples collected from all animals produced 1093 positive results (49.7%). Of bacterial species identified, three accounted for 55.3% of all isolates: Streptococcus uberis (25.6% of positives and 12.7% of total), Staphylococcus epidermidis (16.2% of positives and 8% of total), and Staphylococcus aureus (13.5% of positives and 6.7% of total). Upon investigation of correlations existing among clinical signs and bacterial species responsible for the outbreak, S. uberis showed a statistically significant correlation with serous appearance of milk, presence of clots in secretions, and reactivity of supramammary lymph nodes (p < 0.05); S. epidermidis showed a statistically significant correlation with presence of pustules and ulcers (p < 0.05); and S. aureus showed a statistically significant correlation with clinical signs of chronic mastitis: nodules, abscesses, and atrophy (p < 0.05%). Manual milking techniques were more associated to udder infections than mechanical milking. However, an interesting correlation emerged between presence of S. uberis and mechanical milking with small portable devices. In conclusion, this study revealed interesting and unprecedented correlations among clinical signs, bacterial species isolated from infected milk, and farm management techniques. The results reported here emphasize the primary role played by clinical practice in managing infectious ovine mastitis outbreaks, and strengthen its relevance for recovery of affected flocks

Profile and evolution of antimicrobial resistance of ovine mastitis pathogens (1995–2004)

Antibiograms of selected mastitis pathogens, performed during the decade 1995–2004, were retrospectively analysed in order to evaluate antimicrobial resistance and determine whether resistance changed over time. Results of 2763 strains of Staphylococcus aureus, coagulase negative staphylococci, Streptococcus uberis and Escherichia coli, against penicillin, ampicillin, oxytetracycline, kanamycin and streptomycin are discussed. Strains were isolated in clinical milk samples from sheep suspected of mastitis. The evolution over time of resistance was evaluated by means of logistic regression analysis. The resistance of staphylococci to penicillin appeared to be lower than those usually reported (4.1% of resistant strains in S. aureus; 15.3% for CNS). Higher rates of resistance were observed for aminoglycosides, relevant for S. uberis (84.5% for kanamycin and 92.5% for streptomycin) and S. aureus (14.6% for kanamycin and 63.3% for streptomycin). Overall resistance appeared to confirm the lower resistance in ovine pathogens than in bovine ones. Logistic regression highlighted no trends to increase for resistance over time

Validation of a serological test for the diagnosis of canine rickettsial disease

Canine vector borne diseases include a variety of illnesses affecting domestic dogs worldwide. Clinical abnormalities are often nonspecific during rickettsial infections, and coinfections caused by other tick-transmitted agents may be common. The aim of this study was to validate a differential serological assay for the diagnosis of rickettsial infections by the indirect fluorescent antibody (IFA) test. Sensitivity (DSe), specificity (Dsp), accuracy (Acc), positive and negative predictive values (PPV and NPV), positive and negative likelihood ratios (LR+ and LR−), Cohen's Kappa agreement, Youden's J index and odds values were calculated in order to define the positive and negative post-test probability and to establish a link between clinical signs compatible with a rickettsial infections and serological confirmation

Molecular characterization of enterotoxigenic and borderline oxacillin resistant <i>Staphylococcus strains</i> from ovine milk

Staphylococcal enterotoxins (SEs) produced by Staphylococcus spp. are superantigens responsible for food-poisoning and are associated to mobile genetic elements such as Staphylococcus aureus pathogenicity islands (SaPI). The presence of 13 enterotoxin genes (sea, seb, sec, sed, see, seg, seh, sei, sej, sel, sek, seq, and tst) was tested in 15 S. aureus and 24 coagulase-negative Staphylococcus (CNS) multi-resistant strains isolated from ovine milk in Sardinia. All CNS isolates were enterotoxin-negative, whereas co-presence of sec, sel and tst was observed in most of the S. aureus strains. One isolate of S. aureus was characterized by tst alone. A multiplex PCR assay aimed at discriminating between the integrase genes of pathogenicity islands SaPI2, SaPIbov1, and SaPIMW2 was developed. We demonstrated that strains harboring sec, sel and tst were associated with SaPIbov1, whereas the strain positive for tst was associated with SaPI2. Borderline oxacillin resistant S. aureus strains were also detected. RAPD analysis of the Staphylococcus strains showed that clonal relationships were correlated with pathogenic profiles

Identification of coagulase-negative staphylococci isolated from ovine milk samples by PCR–RFLP of 16S rRNA and <i>gap</i> genes

The identification of coagulase-negative staphylococci (CNS) causing ovine infections remains problematic, although these bacteria are considered the main etiologic agents of subclinical mastitis in sheep and goats. In this study, 226 CNS isolates were collected from 2201 milking sarda sheep belonging to 15 flocks with high somatic cell count scores. All isolates were subjected to identification with the API Staph ID test, and then to the amplification of staphylococcal 16S rRNA and gap genes by PCR assays. The gap gene was subjected to restriction fragment length polymorphism analysis with the restriction endonuclease AluI, whereas the 16S rRNA gene was subjected to ribosomal fingerprinting with the restriction endonucleases RsaI, PstI and AluI. When PCR–RFLP patterns of CNS isolates were different from those of their reference strains, gap gene amplicons were sequenced for definitive identification. The API Staph ID test, in alternative to the genotypic identification method, produced considerably different results in terms of species identified within each group. Using the PCR–RFLP assay, most of the isolates clustered together with the Staphylococcus epidermidis type strain (131, corresponding to 57.9%), followed by S. caprae (34, corresponding to 15%) and S. chromogenes (30, corresponding to 13.2%). In conclusion, the PCR–RFLP assay of 16S rRNA and gap genes is a more reliable and reproducible method than the API Staph ID test for the identification of CNS causing sheep mastitis

Different Strategies for Molecular Differentiation of Mycobacterium bovis Strains Isolated in Sardinia, Italy

Different genetic markers were used to analyze 22 Mycobacterium bovis strains isolated from cattle in Sardinia and one human isolate. IS6110 DNA fingerprinting differentiated the strains into six patterns, whereas with enterobacterial repetitive consensus sequence primers produced seven clusters. PCR ribotyping followed by digestion with HaeIII and PvuII produced five and seven patterns, respectively. PCR with the (GTG)(5) oligonucleotide primer showed the best discriminatory power, generating eight clusters among the strains analyzed

Genetic and pathological characteristics of <i>Cryptococcus gattii</i> and <i>Cryptococcus neoformans</i> var. <i>neoformans</i> from meningoencephalitis in autochthonous goats and mouflons, Sardinia, Italy

In this study, we examined in Sardinia the brain of 555 autochthonous sheep, 50 goats, and 4 mouflons which were found affected by neurological signs. We found 6 goats and one mouflon with meningoencephalitis caused by Cryptococcus sp. There was no evidence of cryptococcal infections in any of the examined sheep. MLST genotyping on Cryptococcus sp. isolates identified Cryptococcus gatti genotype AFLP4/VGI and Cryptococcus neoformans var. neoformans genotype AFLP2/VNIV. Phylogenetically, all Cryptococcus gattii isolates fell within the autochthonous animal, human and environmental Mediterranean isolate cluster, forming a distinct branch along with environmental strains from Alicante, in the southern Mediterranean coast of Spain