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Staphylococcus aureus is a major pathogen causing intramammary infection and mastitis in dairy cows. S. aureus genotypes (GT) can differ significantly in their ability to diffuse and persist in the herd; while the association of virulence gene carriage with epidemiological behavior remains unclear, a role for secreted proteins has been postulated. We characterized the secretome of six S. aureus strains belonging to two genotypes with opposite within-herd prevalence, GTB (high) and GTS (low), corresponding to sequence types (ST) 8 and 398, by high-resolution tandem mass spectrometry and differential analysis with Proteome Discoverer. Data are available via ProteomeXchange with identifier PXD029571. Out of 720 identified proteins, 98 were unique or more abundant in GTB/ST8 and 68 in GTS/ST398. GTB/ST8 released more immunoglobulinbinding proteins, complement and antimicrobial peptide inhibitors, enterotoxins, and metabolic enzymes, while GTS/ST398 released more leukocidins, hemolysins, lipases, and peptidases. Furthermore, GTB/ST8 released the von Willebrand factor protein, staphylokinase, and clumping factor B, while GTS released the staphylococcal coagulase and clumping factor A. Hence, GTB/ST8 secretomes indicated a higher propensity for immune evasion and chronicity and GTS/ST398 secretomes for cellular damage and inflammation, consistent with their epidemiological characteristics. Accordingly, GTS/ST398 secretions were significantly more cytotoxic against bovine PBMCs in vitro. Our findings confirm the crucial role of extracellular virulence factors in S. aureus pathogenesis and highlight the need to investigate their differential release adding to gene carriage for a better understanding of the relationship of S. aureus genotypes with epidemiological behavior and, possibly, disease severity.

Food labels are the main method to ensure that consumers are appropriately informed as regards the food they consume. In Europe, the provision of food information to consumers is regulated by specific laws, including (i) the European Regulation (EU) no 1169/2011, which regulates the mandatory food information including a list of mandatory particulars and nutritional declarations and (ii) the European Regulation (CE) no 1924/2006, concerning the voluntary nutrition and health claims (NHC) made on foods. Nutrient profiling involves the classification and ranking of foods according to their nutritional composition to prevent disease and promote health. For this purpose, the following 14 cheeses were selected (Ager cheese selection) among the Natural Historic Cheeses of Southern Italy: Ragusano PDO; Provola dei Nebrodi PDO; Piacentinu Ennese PDO; Pecorino Siciliano PDO; Vastedda della Valle del Belìce PDO; Caciocavallo Palermitano PAT; Maiorchino PAT; Caprino Nicastrese; Casizolu del Montiferru PAT; Pecorino di Filiano PDO; Canestrato di Moliterno PGI; Pecorino di Carmasciano PAT; Caciocavallo Podolico PAT; Cacioricotta PAT. A total of 173 cheese samples were analysed for moisture, protein, fat, ash, salt and fatty acid (FA) composition. On the basis of moisture content, the Ager cheeses may be classified into semi-hard, with moisture content varying between 35% and 45% (from Provola dei Nebrodi with 35.5% to Vastedda del Belice with 45.6%) and hard-cheese, with moisture content below 35% (from Pecorino di Carmasciano with 27.6%, to Maiorchino with 34.5%). Fat is an important component of cheeses and according to the general standard of cheese, the Ager cheeses can be classified as full fat, with a content of fat in dry matter above to 45% and less than 60% (from Pecorino di Carmasciano with 45.5% to Canestrato di Moliterno and Cacioricotta both with 46.5%) and medium fat, with content above to 25% and less than 45% (from Provola dei Nebrodi with 38.1% to Caciocavallo Podolico with 44.6%). As the saturated FA content, the AGER cheeses show the lowest content in Maiorchino cheese (65.4%) and the highest in Cacioricotta (73.3%). The chemical characteristics of each cheese are strongly linked to the milk species and breed, feeding system, production season and ripening stage. This nutritional information has been made available to producers for the labeling of their cheeses.

Feeding green sulla forage (GSF) (Sulla Coronarium L.), a shortlived perennial legume containing phenolic compounds, especially condensed tannins, showed to increase intake, milk yield and casein level in ruminants, and enhance fatty acid (FA) profile and antioxidant activity of dairy products. To obtain analogous favourable effects using conserved sulla forage, dehydration could be a valid alternative to the haymaking process which causes greater losses of biomass and its nutritional and bioactive compounds. The aim of this research was to evaluate the dairy products from ewes fed with pelleted dehydrated sulla forage (PDSF) in the diet by comparisons with those obtained using sulla hay (SH) and GSF based diets. Twenty primiparous (PR) and pluriparous (PL) milking Valle del Belice ewes were allocated homogeneously into 5 groups and fed 5 diets in a partial 5 × 2 Latin square design with 2 periods. The diets differed for the forage component: SH ad libitum (SHL); 2 kg/d per ewe of PDSF and SH ad libitum (DSF); 2 kg/d of GSF and SH ad libitum (2GSF); 4 kg/d of GSF and SH ad libitum (4GSF); GSF ad libitum (GSFL). Concentrate feed was supplied to PR (0.8 kg/d) and PL (1.2 kg/d) ewes in the function of their different production needs. The results confirmed the superiority of diet in which GSF was the only forage source offered ad libitum, as occurs with grazing; in fact, the GSFL diet resulted in higher milk yield and casein content and enhanced in cheese the number of polyphenols and antioxidant vitamins A and E, the oxidative stability, and the level of health polyunsaturated FA (PUFA) such as rumenic, the main of conjugated linoleic acids (C18:2c9t11), and α-linolenic (ALA, C18:3n-3). On the whole, the DSF diet showed better results than SHL and was comparable to the 4GSF diet for milk yield and casein level and, in cheese, for external colour and vitamin A and total PUFA contents; moreover, ALA was detected at the same high level in DSF and GSFL cheeses. Thus, dehydration seems to represent a valid opportunity to exploit the considerable potential of sulla forage, and maintain adequate production levels and nutritional and health properties of milk and cheese in periods of insufficient grazed green resources.

Subclinical mastitis by Staphylococcus aureus (SAU) and by non-aureus staphylococci (NAS) is a major issue in the water buffalo. To understand its impact on milk, 6 quarter samples with >3,000,000 cells/mL (3 SAU-positive and 3 NAS-positive) and 6 culture-negative quarter samples with

Streptococcus uberis, an environmental pathogen responsible also for contagious transmis-sion, has been increasingly implicated in clinical mastitis (CM) cases in Europe. We described a 4-month epidemiological investigation of Strep. uberis CM cases in an Italian dairy farm. We deter-mined molecular characteristics and phenotypic antimicrobial resistance of 71 Strep. uberis isolates from dairy cows with CM. Genotypic variability was investigated via multiplex PCR of housekeeping and virulence genes, and by RAPD-PCR typing. Antimicrobial susceptibility was assessed for 14 antimicrobials by MIC assay. All the isolates carried the 11 genes investigated. At 90% similarity, two distinct clusters, grouping 69 of the 71 isolates, were detected in the dendrogram derived from the primer ERIC1. The predominant cluster I could be separated into two subclusters, containing 38 and 14 isolates, respectively. Strep. uberis strains belonging to the same RAPD pattern differed in their resistance profiles. Most (97.2%) of them were resistant to at least one of the drugs tested, but only 25.4% showed a multidrug resistance phenotype. The highest resistance rate was observed for lincomycin (93%), followed by tetracycline (85.9%). This study confirmed a low prevalence of β-lactam resistance in Strep. uberis, with only one isolate showing resistance to six antimicrobial classes, including cephalosporins.

Avoiding a Cognitive MonsterAlthough expertise is usually considered as a positive outcome of education and practice in domains as varied as sports, science, music and politics, there are also concerns about negative effects of expertise. Since expertise is facilitated largely by implicit, automatic cognitive and brain processes, it can also lead to undesirable consequences in the form of stereotypical, discriminatory or inflexible responses. Indeed, such responses can at times even be inconsistent with the explicit and intentional choices of an expert. Explaining this phenomenon, it is argued that an expert’s performance can be considered as selecting in a given situation a preferred option for action from a ‘Sculpted Space of Actions’ (Keestra, 2014), which contains more, more complex and better differentiated action representations than a beginner’s space of actions. Integrating this account with the cognitive neuroscientific theory of Predictive Processing, it is argued how mitigating undesirable effects of expertise depends upon awareness and control of the processes involved. Education should therefore provide for insights in and techniques for controlling the cognitive and brain processes that constitute expertise.

Two types of lamb rennet pastes, traditional (A) and industrial (B), were used for making two types of PDO Fiore Sardo cheese (FSA and FSB) to ascertain the influence of their use on cheese characteristics. Traditional rennet was produced from the stomachs of lambs fed only milk and slaughtered, after suckling, on a full stomach. Industrial rennet was produced from the stomachs of lambs weaned and slaughtered on an empty stomach. The cheeses were significantly different (Po0.01) in pH values and pH 4.6-soluble N/total N throughout ripening. FSA cheese had a higher rate of proteolytic activity. Within 240 d of ripening, as1-CN was degraded completely whereas b-CN was partly hydrolysed by plasmin, irrespective of the rennet paste preparation. A number of phosphopeptides were detected in fresh cheeses, which were progressively shortened and dephosphorylated during ripening. In FSA cheese, greater amounts of free fatty acids were released, in particular butyric acid.

The aim of this study was to compare the proteolytic activity by incubating whole ovine casein with 6 industrial (liquid and paste) and two traditional (paste) rennet preparations from calf, lamb and kid. Casein hydrolysate was analysed by pH 8.6 urea-PAGE analysis and immunoblotting using polyclonal antibodies against αs1 and β-casein (CN). The degradation patterns showed that αs1-CN was hydrolysed more quickly than β-CN giving rise to αs1-I casein. The highest degree of proteolysis was observed in 3 types of industrial rennet, two from lamb, either liquid or paste, and one liquid from calf. Rennet from kid (industrial or traditional/liquid or paste) showed the lowest proteolytic activity. The pepsin content was very different among the tested rennet samples, probably explaining the difference in proteolytic activity.