Sequence types and pleuromutilin susceptibility of Brachyspira hyodysenteriae isolates from Italian pigs with swine dysentery: 2003–2012

Swine dysentery is a mucohaemorrhagic colitis of pigs caused by infection with Brachyspira hyodysenteriae. The disease can be controlled by treatment with antimicrobial agents, with the pleuromutilins tiamulin and valnemulin being widely used. In recent years, the occurrence of B.hyodysenteriae with reduced susceptibility to these drugs has been increasing. The aim of this study was to determine temporal changes in genetic groups and pleuromutilin susceptibility amongst B.hyodysenteriae isolates from Italy. Multilocus sequence typing (MLST) was performed on 108 isolates recovered from 87 farms in different regions of Italy from 2003 to 2012, and their minimum inhibitory concentrations (MICs) for tiamulin and valnemulin were determined. Logistic regression was performed to assess associations between susceptibility to the two antimicrobial agents and genetic group, year and region of isolation. The isolates were allocated to 23 sequence types (STs), with five clonal clusters (Ccs) and seven singletons. More than 50% of isolates were resistant to both pleuromutilins (MIC >2.0 μg/mL for tiamulin and >1.0 μg/mL for valnemulin). All 10 isolates in ST 83 were resistant; these were first isolated in 2011 and came from nine farms, suggesting recent widespread dissemination of a resistant strain. Significant associations were found between the proportion of pleuromutilin susceptible isolates and the genetic group and year of isolation. Although resistant isolates were found in all Ccs, isolates in Ccs 2 and 7 were over five times more likely to be susceptible than those in the other Ccs. A significant trend in the reduction of susceptibility over time also was observed

Benign external hydrocephalus: a review, with emphasis on management

Benign external hydrocephalus in infants, characterized by macrocephaly and typical neuroimaging findings, is considered as a self-limiting condition and is therefore rarely treated. This review concerns all aspects of this condition: etiology, neuroimaging, symptoms and clinical findings, treatment, and outcome, with emphasis on management. The review is based on a systematic search in the Pubmed and Web of Science databases. The search covered various forms of hydrocephalus, extracerebral fluid, and macrocephaly. Studies reporting small children with idiopathic external hydrocephalus were included, mostly focusing on the studies reporting a long-term outcome. A total of 147 studies are included, the majority however with a limited methodological quality. Several theories regarding pathophysiology and various symptoms, signs, and clinical findings underscore the heterogeneity of the condition. Neuroimaging is important in the differentiation between external hydrocephalus and similar conditions. A transient delay of psychomotor development is commonly seen during childhood. A long-term outcome is scarcely reported, and the results are varying. Although most children with external hydrocephalus seem to do well both initially and in the long term, a substantial number of patients show temporary or permanent psychomotor delay. To verify that this truly is a benign condition, we suggest that future research on external hydrocephalus should focus on the long-term effects of surgical treatment as opposed to conservative management

ANTIMICROBIAL RESISTANCE OF ESCHERICHIA COLI F4+ STRAINS ISOLATED FROM SWINE IN THE PERIOD 2008-2011

Objectives - The aim of this study was to evaluate the antimicrobial trend in resistance of F4+ Escherichia coli isolated from pigs with E. coli diarrhea. Materials and methods - One hundred-nineteen F4+ pathogenic Escherichia coli isolated from diseased pigs in Northern Italy from 2008 to 2011 were analyzed for their susceptibility to 14 antimicrobials by disk diffusion method. The trend of resistance was determined using the χ2 test grouping the strains into two groups (isolates 2008-2009 and 2010-2011). Results - Isolates showed a statistically significant increasing trend of resistance to cefquinome (from 11% to 24%), danofloxacin (from 14% to 35%), enrofloxacin (from 27% to 32%) and florfenicol (from 21% to 32%). Resistance to the remaining 10 antimicrobial agents tested (aminosidine 33%-35%, gentamicin 27%-31%, flumequine 32%-34%, marbofloxacin 22%-28%, apramycin 45%-46%, colistin 9%-11%, trimethoprim-sulphonamide 48%-42%, thiamphenicol 82%-84%, tetracycline 95%-96%, erythromycin 90%-92% did not change significantly over the study period. On the basis of antimicrobial multi-resistance the strains were collected into three groups: 1. strains resistant to 1-5 antimicrobials (23/119); 2. to 6-10 antimicrobials (73/119); 3. > 10 antimicrobials (23/119). Over the study period, the number of isolates belonging to the first, second and third group showed a significant decreasing trend (P<0.05; R -0.89), no significant change and an increasing trend (P<0.05; R 0.84) respectively. Conclusions - The results of this study indicate an increasing trend to cefquinome, danofloxacin, enrofloxacin and florfenicol in E. coli F4+ isolates. A significant increasing of multi-resistant strains was observed from 2008 to 2011. This indicates the need for continued surveillance studies so that appropriate strategies can be developed to contrast the development of resistance in these and other pathogens

Serological characterisation of Haemophilus parasuis strains in Italy

ISBN 978-3-9813721-0-

HAEMOPHILUS PARASUIS SEROVARS ISOLATED FROM PATHOLOGICAL SAMPLES IN NORTHERN ITALY

From January 2007 to December 2011, a total of 106 Haemophilus parasuis strains isolated from pigs were serotyped by agar gel diffusion test (DG). Serovar 4 was the most prevalent (24.5%), followed by serovar 13 (19.8%) and serovar 5 (11.3%). Twenty-nine strains were non-typeable (27.3%). The strains were divided into two groups, depending on whether they were isolated from specific pathological lesions of systemic disease such as polyserositis, arthritis or meningitis (73 cases of 106) or from the lower respiratory tract of pigs suffering from bronchopneumonia (33 cases of 106). Serovars 4 and 13 had a higher prevalence in systemic infection (polyserositis) than in respiratory disease only. Pasteurella multocida (14/106), Streptococcus suis (7/106), Actinobacillus pleuropneumoniae (4/106), Bordetella bronchiseptica (3/106) and Arcanobacterium pyogenes (3/106) were isolated in association with H. parasuis

Antimicrobial Resistance of F4+ Escherichia Coli Isolated from Swine in Italy

Four-hundred and forty-two F4+ pathogenic Escherichia coli were isolated in a period of 10 years (2002–2011), from pigs that were suffering from diarrhoea belonging to Italian swine herds. The strains were analysed for their susceptibility to 12 antimicrobials using the disc diffusion method. During the study period, a statistically significant proportion of isolates resistant to enrofloxacin (14.5–89.3%), marbofloxacin (5.4–60.7%), flumequine (49.1–92.9%), danofloxacin (21.6–80%), florfenicol (9.8–64.3%), thiamphenicol (50–92%) and cefquinome (3.8–44%) was recorded. An increase in resistance (not statistically significant) to gentamicin (63.6–85.7%), apramycin (61.8–82.1%), trimethoprim-sulphamethoxazole (75–89.3%), tetracycline (97–100%) and erythromycin (92.4–100%) was also observed. Based on antimicrobial multiresistance, the strains were collected into three groups: I. resistant to 2–5 antimicrobials; II. resistant to 6–8 antimicrobials; III. resistant to 9–12 antimicrobials. The number of isolates belonging to the first group showed a statistically significant decrease (P < 0.05; R2 = 0.896; r = −0.9608), while the isolates belonging to the second and third groups showed a statistically significant increase in resistance (P < 0.05; R2 = 0.753; r = 0.8890 and P < 0.05; R2 = 0.727; r = 0.8701, respectively) over the period of study. The results of this study suggest the need for continued monitoring of the development of resistance

Effect of added dietary threonine on growth performance, health, immunity and gastrointestinal function of weaning pigs with differing genetic susceptibility to Escherichia coli infection and challenged with E.\ua0coli K88ac

Threonine (Thr) is important for mucin and immunoglobulin production. We studied the effect of added dietary Thr on growth performance, health, immunity and gastrointestinal function of weaning pigs with differing genetic susceptibility to E. coli K88ac (ETEC) infection and challenged with ETEC. Forty-eight 24-day-old weaned pigs were divided into two groups by their ETEC susceptibility using mucin 4 (MUC4) gene as a marker (2 MUC4-/-, not-susceptible, and 2 MUC4+/+, susceptible, pigs per litter). Within genotype, pigs were fed two different diets: 8.5 (LThr) or 9.0 (HThr) g Thr/kg. Pigs were orally challenged on day 7 after weaning and slaughtered on day 12 or 13 after weaning. Before ETEC challenge, HThr pigs ate more (p < 0.05). The diet did not affect post-challenge growth, but HThr tended to increase post-challenge feed efficiency (p = 0.087) and overall growth (p = 0.087) and feed efficiency (p = 0.055). Before challenge, HThr pigs excreted less E. coli (p < 0.05), while after challenge, diet did not affect the number of days with diarrhoea and ETEC excretion. MUC4+/+ pigs responded to the challenge with more diarrhoea, ETEC excretion and anti-K88 IgA in blood and jejunal secretion (p < 0.001). HThr pigs had a higher increase of anti-K88 IgA values in jejunal secretion (p = 0.089) and in blood (p = 0.089, in MUC4+/+ pigs only). Thr did not affect total IgA and IgM values, morphometry of jejunum, goblet cells count in colon, total mucin from jejunum and colon, but varied jejunal goblet cells counts (p < 0.05). In the first two post-weaning weeks, 8.5 g Thr/kg diet may be not sufficient to optimize initial feed intake, overall feed efficiency and intestinal IgA secretion and to control the gut microbiota in the first post-weaning week, irrespective of the pig genetic susceptibility to ETEC infection

STUDIO DELLE MANIFESTAZIONI CLINICHE, ELLA MODIFICAZIONI ANATOMICHE E DEL PATTERN INFIAMMATORIO CITOCHINICO NEL LIQUIDO BRONCO-ALVEOLARE IN SUINI AFFETTI DA MALATTIA RESPIRATORIA ACUTA SPONTANEA DA ACTINOBACILLUS PLEUROPNEUMONIAE: IMPLICAZIONI TERAPEUTICHE

Scopo del presente lavoro è stato la valutazione dell’evoluzione delle manifestazioni cliniche, dei quadri radiografici polmonari in vivo e del pattern infiammatorio/immunitario citochinico nel liquido bronco-alveolare (BALF) e nel siero di suini sottoposti a trattamento antibatterico con amoxicillina per il controllo della malattia respiratoria acuta spontanea sostenuta da Actinobacillus pleuropneumoniae. Lo studio è stato compiuto su suini ibridi commerciali con malattia respiratoria spontanea acuta. Gli animali sono stati monitorati per 20 giorni dopo somministrazione intramuscolare di amoxicillina effettuata all’esordio della sintomatologia. La sintomatologia clinica respiratoria, la mortalità correlata, le lesioni polmonari e la presenza di agenti batterici e virali responsabili di co-infezione sono state determinate rispettivamente mediante score clinico, esame radiografico, indagini batteriologiche sul BALF e sierologia; la reattività infiammatoria/immunitaria è stata valutata come livelli di citochine pro-infiammatorie (IL-1β, IL-6, IL-8, MCP-1, TNF-α)/immunitarie (IL-10) e proteine di fase acuta (CRP, aptoglobina, LBP) mediante ELISA e real-time PCR. Si è evidenziato un decorso clinico della patologia respiratoria caratterizzato da una fase iniziale di acuzie associata a lesioni polmonari radiografiche a carattere di consolidamento prevalentemente a livello delle porzioni dorso-caudali ed una successiva evoluzione fino alla pressoché completa remissione dei sintomi. La mortalità è stata riconducibile a pleuropolmonite da Actinobacillus pleuropneumoniae biotipo 1, sierotipo 9. I markers infiammatori hanno mostrato un incremento iniziale e successiva riduzione in associazione all’evoluzione della malattia respiratoria, pur con variazioni individuali e con tipologia di andamento differente. Anche se caratterizzato da maggior variabilità, l’andamento della citochina immunoregolatrice negativa IL-10 si è modificato in relazione allo stato infiammatorio, a testimonianza di una regolazione concertata tra meccanismi di reattività cellulare in presenza di infezione. Abstract. The aim of the present work was the evaluation of the evolution of the clinical signs, pulmonary lesions at radiography and inflammatory/immune cytokine patterns in bronchoalveolar lavage fluid (BALF) and serum of pigs treated with amoxicillin for the control of spontaneous acute respiratory disease sustained by Actinobacillus pleuropneumoniae. The study was performed using crossbred conventional pigs showing acute respiratory disease; the animals were monitored for 20 days after intramuscular administration of amoxicillin at the onset of clinical signs. Respiratory clinical signs, mortality associated with respiratory disease, pulmonary lesions and the presence of bacteria and viruses responsible of co-infections were determined respectively by clinical scores, radiography, bacteriology on BALF and serology; the inflammatory/immune reactivity was evaluated as levels of pro-inflammatory (IL-1β, IL-6, IL-8, MCP-1, TNF-α)/immune (IL-10) cytokines and acute phase proteins (CRP, haptoglobin, LBP) by ELISA and real-time PCR. Clinical, microbiological, radiological and biochemical-clinical analyses did not show different outcome among animals. All subjects showed a clinical outcome of acute respiratory disease characterized by pulmonary consolidation (especially dorsal-caudal) radiographic views. Mortality was due to pleuropneumonia associated with Actinobacillus pleuropneumoniae biotype 1, serotype 9. The pro-inflammatory markers showed an increase and subsequent decrease associated with the development of respiratory disease, despite individual levels and courses were different. The IL-10 course resulted more variable and changes in association with the inflammatory cytokine levels, testifying a concerted regulation of cellular reactivity following infection

Comparison of three patterns of feed supplementation with live Saccharomyces cerevisiae yeast on postweaning diarrhea, health status, and blood metabolic profile of susceptible weaning pigs orally challenged with Escherichia coli F4ac

The development of effective feeding strategies to reduce the detrimental effect of enterotoxigenic F4ac (ETEC) plays a crucial role in reducing the occurrence of therapeutic intervention with antibiotics in livestock. The ability of CNCM I-4407 (SCC), supplied in different patterns to counteract ETEC infection in weaned pigs, was evaluated. Fifty pigs weaned at 24 d were then divided into 5 groups: control (CO), CO + colistin (AB), CO + 5 7 10(10) cfu of SCC/ kg feed, from d 0 to 21 (PR), CO + 5 7 10(10) cfu of SCC/ kg feed from d 7 to 11 (CM), and CO + 1 shot of 2 7 10(11) cfu of SCC when the first diarrhea appeared (CU). On d 7 postweaning, all the pigs were orally challenged with 10(8) cfu of ETEC. Blood samples were taken from the pigs (d 7, 8, 12, and 21) while the fecal excretion of ETEC was assessed on d 7 and 10. Fecal consistency was scored from 12 h before infection to 144 h postinfection (p.i.). On d 21, the pigs were sacrificed. The in vitro adhesion test on the intestinal villi confirmed individual susceptibility to ETEC, excluding the presence of resistant pigs. Growth performance did not differ between the treatments. Mortality was reduced in the AB group (P< 0.01) and, marginally, in the PR group (P = 0.089) when compared to the CO group. The CO group had a higher fecal score than AB in the period of observation (from P = 0.01 to P< 0.001). Yeast administration reduced the fecal score when compared to the CO group 12 and 48 h p.i. (P = 0.04). Total IgA never differed among the treatments, but the ETEC-specific IgA concentration was lower in the AB group than in CO (P = 0.04) at d 12. Four days p.i., the pigs fed live yeast had reduced ETEC excretion compared with the CO pigs (P = 0.05). Blood concentrations of dodecenoyl-L-carnitine (P < 0.01), glutaryl-L-carnitine/hydroxyhex\uacanoyl-L-carnitine, phosphatidylcholine diacyl and phosphatidylcholine diacyl (P = 0.01 and P< 0.01, respectively), and \u3b1-amino adipic acid (P < 0.01) were reduced in the AB group compared to the CO group; PR + CM reduced the concentration of sphingomyelin-ceramide (P = 0.02) and increased the concentration of decadienyl-L-carnitine (C10:2; P= 0.02) vs. CO. The CM group had an increased concentration of C10:2 (P < 0.01) compared to the PR group. In conclusion, the administration of live yeast, even in concomitance with ETEC infections, reduces pig illness and mortality. The strain of SCC tested did not show a therapeutic effect

Sequence types and pleuromutilin susceptibility of Brachyspira hyodysenteriae isolates from Italian pigs with swine dysentery: 2003-2012

Swine dysentery is a mucohaemorrhagic colitis of pigs caused by infection with Brachyspira hyodysenteriae. The disease can be controlled by treatment with antimicrobial agents, with the pleuromutilins tiamulin and valnemulin being widely used. In recent years, the occurrence of B. hyodysenteriae with reduced susceptibility to these drugs has been increasing. The aim of this study was to determine temporal changes in genetic groups and pleuromutilin susceptibility amongst B. hyodysenteriae isolates from Italy. Multilocus sequence typing (MLST) was performed on 108 isolates recovered from 87 farms in different regions of Italy from 2003 to 2012, and their minimum inhibitory concentrations (MICs) for tiamulin and valnemulin were determined. Logistic regression was performed to assess associations between susceptibility to the two antimicrobial agents and genetic group, year and region of isolation. The isolates were allocated to 23 sequence types (STs), with five clonal clusters (Ccs) and seven singletons. More than 50% of isolates were resistant to both pleuromutilins (MIC > 2.0 µg/mL for tiamulin and > 1.0 µg/mL for valnemulin). All 10 isolates in ST 83 were resistant; these were first isolated in 2011 and came from nine farms, suggesting recent widespread dissemination of a resistant strain. Significant associations were found between the proportion of pleuromutilin susceptible isolates and the genetic group and year of isolation. Although resistant isolates were found in all Ccs, isolates in Ccs 2 and 7 were over five times more likely to be susceptible than those in the other Ccs. A significant trend in reduction of susceptibility over time also was observed