Determination of gastrointestinal tract colonization sites from feedlot cattle transiently shedding or super-shedding Escherichia coli O157:H7 at harvest.

AIMS: The objective of the study was to determine levels of Escherichia coli O157:H7 colonization in the gastrointestinal tract (GIT) of naturally shedding cattle shedding the pathogen at low- or super-shedder levels. METHODS AND RESULTS: Over 2 years, feedlot cattle were sampled multiple times for faecal shedding of E. coli O157:H7. Just prior to harvest (1-2 days), animals that were super-shedders (≥104  CFU per gram of faeces) were specifically identified, and based on the longer term screening data, pen cohorts that were low-shedders (years 1 and 2) or chronic-shedders (year 1) were also identified. At harvest, samples were collected from throughout the GIT, including the rectoanal junction (RAJ) for enumeration and enrichment of E. coli O157:H7. The mouth samples exhibited the greatest prevalence for the pathogen, and the abomasum and rumen exhibited the lowest prevalence (P < 0·05). Super-shedders had significantly greater prevalence for all GIT locations except the mouth and abomasum compared to low-shedders, but the super-shedders were the only animals with positive abomasum samples. Samples from the super-shedders were enumerable for most GIT locations, and the rectum and RAJ locations were the only locations that were significantly greater than other locations (P < 0·05). CONCLUSIONS: Across all animals naturally exposed to E. coli O157:H7, the risk of ingestion is high, but rumen and abomasum are potential barriers to passage. In super-shedders, the passage through the GIT was greater, allowing colonization in the rectum and at the RAJ. SIGNIFICANCE AND IMPACT OF THE STUDY: Escherichia coli O157:H7 low-shedding cattle had lower pathogen levels throughout the GIT, indicating intrinsic GIT factors to these cattle may reduce pathogen passage through the GIT, including the abomasum, and minimize risk of RAJ colonization.

The impact of the bovine faecal microbiome on Escherichia coli O157:H7 prevalence and enumeration in naturally infected cattle.

AIMS: The objective of this study was to determine if the faecal microbiome has an association with Escherichia coli O157:H7 prevalence and enumeration. METHODS AND RESULTS: Pyrosequencing analysis of faecal microbiome was performed from feedlot cattle fed one of three diets: (i) 94 heifers fed low concentrate (LC) diet, (ii) 142 steers fed moderate concentrate (MC) diet, and (iii) 132 steers fed high concentrate (HC) diet. A total of 322 585 OTUs were calculated from 2,411,122 high-quality sequences obtained from 368 faecal samples. In the LC diet group, OTUs assigned to the orders Clostridiales and RF39 (placed within the class Mollicutes) were positively correlated with both E. coli O157:H7 prevalence and enumeration. In the MC diet group, OTUs assigned to Prevotella copri were positively correlated with both E. coli O157:H7 prevalence and enumeration, whereas OTUs assigned to Prevotella stercorea were negatively correlated with both E. coli O157:H7 prevalence and enumeration. In both the MC diet group and the HC diet group, OTUs assigned to taxa placed within Clostridiales were both positively and negatively correlated with both E. coli O157:H7 prevalence and enumeration. However, all correlations were weak. In both the MC diet group and the HC diet group, stepwise linear regression through backward elimination analyses indicated that these OTUs were significantly correlated (P < 0·001) with prevalence or enumeration, explaining as much as 50% of variability in E. coli O157:H7 prevalence or enumeration. CONCLUSIONS: Individual colonic bacterial species have little impact on E. coli O157:H7 shedding but collectively groups of bacteria were strongly associated with pathogen shedding. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacterial groups in the bovine colon may impact faecal shedding of the zoonotic pathogen E. coli O157:H7, and manipulation of the intestinal microbiota to alter these bacteria may reduce shedding of this pathogen and foodborne illnesses.

Differential gene expression in the duodenum, jejunum and ileum among crossbred beef steers with divergent gain and feed intake phenotypes.

Small intestine mass and cellularity were previously associated with cattle feed efficiency. The small intestine is responsible for the digestion of nutrients and absorption of fatty acids, amino acids and carbohydrates, and it contributes to the overall feed efficiency of cattle. The objective of this study was to evaluate transcriptome differences among the small intestine from cattle with divergent gain and feed intake. Animals most divergent from the bivariate mean in each of the four phenotypic Cartesian quadrants for gain × intake were selected, and the transcriptomes of duodenum, jejunum and ileum were evaluated. Gene expression analyses were performed comparing high gain vs. low gain animals, high intake vs. low intake animals and each of the phenotypic quadrants to all other groups. Genes differentially expressed within the high gain-low intake and low gain-high intake groups of animals included those involved in immune function and inflammation in all small intestine sections. The high gain-high intake group differed from the high gain-low intake group by immune response genes in all sections of the small intestine. In all sections of small intestine, animals with low gain-low intake displayed greater abundance of heat-shock genes compared to other groups. Several over-represented pathways were identified. These include the antigen-processing/presentation pathway in high gain animals and PPAR signaling, starch/sucrose metabolism, retinol metabolism and melatonin degradation pathways in the high intake animals. Genes with functions in immune response, inflammation, stress response, influenza pathogenesis and melatonin degradation pathways may have a relationship with gain and intake in beef steers.

Evaluation of essential oils in beef cattle manure slurries and applications of select compounds to beef feedlot surfaces to control zoonotic pathogens.

AIMS: To evaluate natural terpene compounds for antimicrobial activities and determine whether these compounds could be used to control microbial activities and pathogens in production animal facilities. METHODS AND RESULTS: Thymol, geraniol, glydox, linalool, pine oil, plinol and terpineol were tested in laboratory studies for ability to control the production of odorous volatile fatty acid compounds and reduce pathogen levels in manure slurry preparations. Thymol is a terpene phenolic compound and was most effective for reducing fermentation products and pathogen levels (P < 0.05), followed by the extracts linalool, pine oil and terpineol, which are terpene alcohols. Select compounds thymol, linalool and pine oil were further evaluated in two separate studies by applying the agents to feedlot surfaces in cattle pens. Feedlot surface material (FSM; manure and soil) was collected and analysed for fermentation products, levels of coliforms and total Escherichia coli, and the presence of E. coli O157:H7, Campylobacter, Salmonella, Listeria and L. monocytogenes. The reduction in fermentation products but not pathogens was dependent on the moisture present in the FSM. Treatment with 2000 ppm thymol reduced the prevalence of E. coli O157:H7 but not Listeria. In a separate study, treatment with 4000 ppm pine oil reduced E. coli O157:H7, Listeria and Campylobacter (P < 0.05). Linalool was tested at two levels (2000 and 4000 ppm) and did not affect pathogen levels at either concentration. CONCLUSIONS: Natural compounds bearing terpenes can control pathogenic bacteria in treated manures and when applied to the feedlot surface in production cattle systems. Pine oil is a cheaper alternative to thymol and may be a useful treatment for controlling pathogens. SIGNIFICANCE AND IMPACT OF THE STUDY: The control of bacterial pathogens in animal productions systems is an important step in preharvest food safety. Waste products, such as pine oil extract, from the pulp wood industry may have application for treating feedlot pens and manures to reduce the pathogen load.

Effect of lysozyme or antibiotics on faecal zoonotic pathogens in nursery pigs.

AIMS: The objective of this study was to determine the effect of lysozyme and antibiotics on zoonotic pathogen shedding in faeces from nursery pigs housed without and with an indirect disease challenge. METHODS AND RESULTS: Two replicates of approximately 650 pigs each were weaned and randomly assigned to one of 24 pens in either a nursery room that had been fully disinfected or a nursery room left unclean. Pigs were randomly assigned to control diet (Control), control diet + antibiotics (Antibiotic; chlortetracycline and tiamulin), or control diet + lysozyme (Lysozyme; 100 mg kg(-1) diet). Rectal swab samples were collected on day 0 and 28 of treatment, and enriched and cultured for Campylobacter spp. and shiga-toxigenic Escherichia coli (STEC). Enrichments from rectal swab samples also were analysed for presence of enterohaemorrhagic E. coli (EHEC) virulence genes (hlyA, eae, stx1 and stx2). Room hygiene had little effect on day 28 results. Percentage of samples culture positive for Campylobacter spp. was lowest for lysozyme diets (P < 0·01), but similar for control and antibiotic diets (43·2, 83·7, and 84·8 respectively). Diet had little effect on the EHEC virulence genes hlyA or eae (P > 0·1), but there was a tendency for fewer samples positive for stx1/stx2 in antibiotic or lysozyme diet groups (P < 0·07) compared to control diet (1·2, 2·1 and 5·8% respectively). Salmonella spp. and specific STEC types tested were rarely detected in the study. CONCLUSIONS: In nursery swine, room hygiene had little effect on pathogen shedding. Dietary chlortetracycline and tiamulin did not reduce pathogen shedding but dietary lysozyme reduced faecal shedding of Campylobacter. SIGNIFICANCE AND IMPACT OF THE STUDY: Lysozyme can effectively replace antibiotics in the diet of nursery swine and can be effective for pathogen control.

Barriers to mental health treatment: results from the WHO World Mental Health surveys.

BACKGROUND: To examine barriers to initiation and continuation of mental health treatment among individuals with common mental disorders. METHOD: Data were from the World Health Organization (WHO) World Mental Health (WMH) surveys. Representative household samples were interviewed face to face in 24 countries. Reasons to initiate and continue treatment were examined in a subsample (n = 63,678) and analyzed at different levels of clinical severity. RESULTS: Among those with a DSM-IV disorder in the past 12 months, low perceived need was the most common reason for not initiating treatment and more common among moderate and mild than severe cases. Women and younger people with disorders were more likely to recognize a need for treatment. A desire to handle the problem on one's own was the most common barrier among respondents with a disorder who perceived a need for treatment (63.8%). Attitudinal barriers were much more important than structural barriers to both initiating and continuing treatment. However, attitudinal barriers dominated for mild-moderate cases and structural barriers for severe cases. Perceived ineffectiveness of treatment was the most commonly reported reason for treatment drop-out (39.3%), followed by negative experiences with treatment providers (26.9% of respondents with severe disorders). CONCLUSIONS: Low perceived need and attitudinal barriers are the major barriers to seeking and staying in treatment among individuals with common mental disorders worldwide. Apart from targeting structural barriers, mainly in countries with poor resources, increasing population mental health literacy is an important endeavor worldwide.

Effects of antimicrobials fed as dietary growth promoters on faecal shedding of Campylobacter, Salmonella and shiga-toxin producing Escherichia coli in swine.

AIMS: To determine whether antimicrobials commonly used in swine diets affect zoonotic pathogen shedding in faeces. METHODS AND RESULTS: Barrows (n = 160) were sorted into two treatments at 10 weeks of age (week 0 of the study), and fed growing, grow finishing and finishing diets in 4-week feeding periods. For each feeding phase, diets were prepared without (A-) and with (A+) dietary antimicrobials (chlortetracycline, 0-8 week; bacitracin, 9-12 week) typical of the United States. At week 0, 4, 8, 9, 10 and 12 of the study, faecal swabs or grabs were collected for analyses. Campylobacter spp. was absent at week 0, but prevalence increased over time with most isolates being identified as Campylobacter coli. When chlortetracycline was used in A+ diets (week 4 and 8), prevalence for Campylobacter spp., pathogenic Escherichia coli O26 and stx genes was lower in faeces. On week 12 after the shift to bacitracin, Campylobacter spp. and stx genes were higher in faeces from piglets fed A+ diet. Pathogenic E. coli serogroups O103 and O145 were isolated throughout the study and their prevalence did not differ due to diet. Pathogenic E. coli serogroups O111 and O121 were never found in the piglets, and Salmonella spp. prevalence was low. CONCLUSIONS: In production swine, growing diets with chlortetracycline may have reduced pathogen shedding compared with the A-growing diets, whereas finishing diets with bacitracin may have increased pathogen shedding compared with the A-finishing diet. SIGNIFICANCE AND IMPACT OF THE STUDY: Inclusion of antimicrobials in the diet can affect zoonotic pathogen shedding in faeces of swine.

Hyperuricaemia and gout in New Zealand rural and urban Maori and non-Maori communities.

BACKGROUND: There are few current data on the prevalence of hyperuricaemia and gout in New Zealand, particularly among the indigenous Maori population. AIMS: To determine the prevalence of gout and hyperuricaemia in rural and urban Maori and non-Maori community samples and describe the treatment and comorbidities of participants with gout. METHODS: Participants aged 20-64 years were recruited by random selection from the electoral roll. Maori samples were selected from among those identified as being of Maori descent on the roll and who self-identified as being of Maori ethnicity at interview. Personal medical history, blood pressure, anthropometrics, fasting lipids, glucose, HbA1c and urate were recorded. RESULTS: There were 751 participants. Mean serum urate (SU) was 0.30 mmol/L (0.06-0.69 mmol/L). Maori had a significantly higher prevalence of hyperuricaemia (SU > 0.40 mmol/L) compared with non-Maori (17.0% vs 7.5%, P = 0.0003). A total of 57 participants had a history of gout, with a higher prevalence in Maori compared with non-Maori (10.3% vs 2.3%, P < 0.0001). Of the participants, 18/57 (31.6%) with gout were receiving urate-lowering therapy, but in 38.9%, SU was >0.36 mmol/L. Participants with gout were more likely to have metabolic syndrome, diabetes, cardiac disease or hypertension. CONCLUSIONS: Gout and hyperuricaemia were more prevalent in Maori, and participants with gout were more likely to have comorbidities. There was not a higher overall adjusted cardiovascular disease risk in Maori participants with gout. Despite the high prevalence of gout, management remains suboptimal.

Harmful drinking and talking about alcohol in primary care: New Zealand population survey findings.

OBJECTIVE: Existing evidence suggests low recognition of alcohol problems in primary care. This study aimed to determine the 12-month prevalence of harmful or hazardous drinking (HHD) in a population sample and to measure the relationship between HHD and talking about alcohol in primary care consultations in that period. METHOD: A New Zealand population survey of 12 488 adults. Alcohol use in the past 12 months was assessed by the Alcohol Use Disorders Identification Test (AUDIT), with HHD defined as a total score of eight or above. Talking about alcohol was self-reported. RESULTS: HHD was present in 17.7% and was commoner in men and in younger age groups, with the highest prevalence 53.6% in men aged 18-24. Three per cent of those who attended their usual primary care provider in the past 12 months reported being talked to about alcohol. Talking about alcohol increased with AUDIT score, but was not commoner in young people despite their higher prevalence of HHD. Overall, 9.4% of attendees with HHD reported talking about alcohol. CONCLUSION: HHD is common but largely not detected in primary care. Improved detection would permit the delivery of effective treatments such as brief interventions.

Effect of anaerobic digestion temperature on odour, coliforms and chlortetracycline in swine manure or monensin in cattle manure.

AIMS: This study evaluated the effect of anaerobic digestion at 22, 38 and 55°C on odour, coliforms and chlortetracycline (CTC) in swine manure or monensin (MON) in cattle manure. METHODS AND RESULTS: Swine or cattle were fed the respective growth promotant, manure was collected, and 2-l laboratory methane digesters were established at the various temperatures and sampled over 25 or 28 days. After 21 days, the concentration of CTC in the 22, 38 and 55°C swine digester slurries decreased 7, 80 and 98%, respectively. Coliforms in the 22°C digester slurries were still viable after 25 days; however, they were not detectable in the 38 and 55°C slurries after 3 and 1 days, respectively. After 28 days, the concentration of MON in the 22, 38 and 55°C cattle digester slurries decreased 3, 8 and 27%, respectively. Coliforms in the 22°C cattle digester slurries were still viable after 28 days; however, they were not detectable in the 38 and 55°C slurries after 14 and 1 days, respectively. CONCLUSIONS: These studies indicate that anaerobic digestion at 38 or 55°C may be an effective treatment to reduce coliforms and CTC; however, it is not an effective treatment to reduce MON. SIGNIFICANCE AND IMPACT OF THE STUDY: More studies are needed to determine which pharmaceuticals are susceptible to degradation by a specific manure treatment to prevent negative environmental consequences.

Wegener's granulomatosis: treatment and survival characteristics in a high-prevalence southern hemisphere region.

Our aim was to describe the treatment and survival characteristics of Wegener's granulomatosis (WG) in Canterbury, New Zealand. The medical records of 48 patients diagnosed between 1 July 1997 and 31 December 2008 and fulfilling validated classification criteria for WG were reviewed to characterise survivorship in the province of Canterbury, New Zealand. The age at diagnosis was 61 years (range 20 to 83 years) with an equal number of males and females. Using Kaplan-Meier product-limit analysis, the probability of survival at 1 and 10 years was 91% and 62% respectively. Of the 12 deaths in the cohort, four occurred within 12 months of diagnosis: two from pulmonary haemorrhage and two from renal failure. Beyond 12 months, two patients died of renal failure, two of myocardial infarction and one from cardiac arrhythmia, one from cerebrovascular disease and two from colorectal carcinoma. The median time to relapse was 6.75 years, and the probability of relapse within 10 years was 67%. Survivorship, treatment response rate and the rate of relapse from WG in a cohort of patients from this high-prevalence southern hemisphere region were similar to that reported for northern hemisphere cohorts with a similar prevalence.

Comparison of bacterial communities in faeces of beef cattle fed diets containing corn and wet distillers' grain with solubles.

AIM: The mammalian intestinal microflora has been shown to impact host physiology. In cattle, intestinal bacteria are also associated with faecal contamination of environmental sources and human illness via foodborne pathogens. Use of wet distillers' grains with solubles (WDGS) in cattle feed creates a gastrointestinal environment where some bacterial species are enriched. Here, we examine if a diet containing 40% WDGS results in fundamentally different microbial community structures. METHODS AND RESULTS: The 20,002 16S r-RNA gene sequences from 20 beef cattle were analysed using Sanger sequencing methods. At the genus level, Prevotella (Gram negative) and Anaerobacter (Gram positive) were the most frequently occurring bacteria in our beef cattle faecal samples. Diet-associated differences in prevalence were noted for Prevotella but not Anaerobacter. CONCLUSIONS: Diet affects community structure. Faecal communities of co-housed beef cattle are not identical. SIGNIFICANCE AND IMPACT OF THE STUDY: It is known that a diet of 40% corn-based WDGS increases the generic Escherichia coli in the faeces and enriches E. coli O157:H7. The results from the current study suggest that in addition to previously observed changes in E. coli, the entire bacterial community structure is different for animals fed 40% corn-based WDGS compared to a traditional corn-finishing diet.

Association of angiopoietin-2, C-reactive protein and markers of obesity and insulin resistance with survival outcome in colorectal cancer.

BACKGROUND: This study investigated the relationship of obesity, insulin resistance, inflammation and angiogenesis with cancer progression and survival in a colorectal cancer cohort. METHODS: Clinical and pathological data, along with anthropometric and follow-up data, were collected from 344 consecutive colorectal cancer patients. Serum samples at diagnosis were analysed by immunoassay for adiponectin, C-reactive protein (CRP), vascular endothelial growth factor-A (VEGF-A), angiopoietin-2 (Ang-2), insulin-like growth factor-1 (IGF-1), insulin and C-peptide. RESULTS: Serum Ang-2 and VEGF-A levels increased with tumour T stage (P=0.007 and P=0.025, respectively) and N stage (P=0.02 and P=0.03, respectively), and correlated with CRP levels (r=0.43, P<0.001 and r=0.23, P<0.001, respectively). Angiopoietin-2 correlated with C-peptide (r=0.14, P=0.007) and VEGF-A with IGF-1 in males (r=0.25, P=0.001). Kaplan-Meier analysis showed that patients with high serum levels of CRP and Ang-2 had significantly reduced survival (both P≤0.001). After adjusting for tumour stage and age, Ang-2 remained a significant predictor of survival. The CRP levels were inversely associated with survival in American Joint Committee on Cancer stage II patients (P=0.038), suggesting that CRP could be used to support treatment decisions in this subgroup. Serum markers and anthropometric measures of obesity correlated with each other, but not with survival. CONCLUSION: Our study supports the concept that obesity-related inflammation, rather than obesity itself, is associated with colorectal cancer progression and survival. The study confirms serum Ang-2 as a predictive marker for outcome of colorectal cancer.

A latent class analysis of psychosis-like experiences in the New Zealand Mental Health Survey.

OBJECTIVE: To describe the underlying structure of psychosis-like experiences in the New Zealand Mental Health Survey. METHOD: A nationwide survey of household residents aged 16+ years was undertaken (n = 7435), using the Composite International Diagnostic Interview (3.0), including a six question lifetime screener for psychosis. Participants were grouped in three ways: by the number of 'symptoms' (occurring when not dreaming, half-asleep or under the influences of drugs) and by latent classes derived from binary responses (no/yes) or ordinal responses (never/sub-threshold/few times/many times). RESULTS: Psychosis-like events were not uncommon (7.3%; 95% CIs 6.5-8.1), particularly experiences of visual (5.3%; 95% CIs 4.7-6.0) or auditory hallucinations (2.8%; 95% CIs 2.3-3.3). Both latent class analyses indicated a 'normal' class, a 'hallucinatory class' and a 'psychotic' class. The lifetime probability of anxiety, mood or substance disorders and the lifetime probability of seeking help for mental health problems increased from 'normal' to 'hallucinatory' to 'psychotic' classes and with the 'symptom' count. CONCLUSION: The presence of sub-threshold events and variation in the number of times a 'symptom' is experienced suggest a psychosis continuum. However, the latent classes labelled 'hallucinatory' and 'psychotic' differ markedly in symptomatology, which suggests some form of discrete clustering.

Association of single nucleotide polymorphisms in the ANKRA2 and CD180 genes with bovine respiratory disease and presence of Mycobacterium avium subsp. paratuberculosis(1).

The objective was to determine whether single nucleotide polymorphisms (SNPs) in the ANKRA2 and CD180 genes are associated with incidence of bovine respiratory disease (BRD) and presence of Mycobacterium avium subsp. paratuberculosis (MAP) in cattle. Two independent populations were used. The first population (BRD-affected; N = 90) was composed of 31 half-sib progeny, from a Brahman × Angus sire, that were treated for BRD. Untreated offspring from the sire were selected to serve as controls. The second population (MAP-infected) of 330 animals of unknown parentage was evaluated for the presence of MAP in ileocecal lymph node and classified as positive or negative. Markers in both genes were assessed for association in these two populations. In the BRD-affected population, five SNPs in the ANKRA2 gene were significantly associated (P < 0.05), and two SNPs were highly associated (P < 0.01) with incidence of BRD. In addition, two SNPs in the CD180 gene were found to be associated with this trait. In the MAP-infected population, one SNP in the ANKRA2 gene was significantly associated (P < 0.05) with the presence or absence of MAP, and a SNP in the CD180 gene was highly associated (P < 0.01) with the trait. Haplotypes, using significant markers, showed a positive association with both incidence of BRD (P = 0.0001) and with the presence of MAP (P = 0.0032). Markers in the ANKRA2 and CD180 genes are associated with the ability of the animal to cope with pathogens.

Gender and the relationship between marital status and first onset of mood, anxiety and substance use disorders.

BACKGROUND: Prior research on whether marriage is equally beneficial to the mental health of men and women is inconsistent due to methodological variation. This study addresses some prior methodological limitations and investigates gender differences in the association of first marriage and being previously married, with subsequent first onset of a range of mental disorders. METHOD: Cross-sectional household surveys in 15 countries from the WHO World Mental Health survey initiative (n=34493), with structured diagnostic assessment of mental disorders using the Composite International Diagnostic Interview 3.0. Discrete-time survival analyses assessed the interaction of gender and marital status in the association with first onset of mood, anxiety and substance use disorders. RESULTS: Marriage (versus never married) was associated with reduced risk of first onset of most mental disorders in both genders; but for substance use disorders this reduced risk was stronger among women, and for depression and panic disorder it was confined to men. Being previously married (versus stably married) was associated with increased risk of all disorders in both genders; but for substance use disorders, this increased risk was stronger among women and for depression it was stronger among men. CONCLUSIONS: Marriage was associated with reduced risk of the first onset of most mental disorders in both men and women but there were gender differences in the associations between marital status and onset of depressive and substance use disorders. These differences may be related to gender differences in the experience of multiple role demands within marriage, especially those concerning parenting.

The effects of dietary additives on faecal levels of Lactobacillus spp., coliforms, and Escherichia coli, and faecal prevalence of Salmonella spp. and Campylobacter spp. in US production nursery swine.

AIMS: In the United States, carbadox and copper sulfate are growth promoters commonly used in combination in nursery swine diets. Our aim was to determine how selected dietary additives affect selected bacterial populations and pathogens in nursery swine, and compare to larch extract, which contains potential antibacterial activities. METHODS AND RESULTS: Piglets were weaned and sorted into one of the four treatments: (i) basal diet without antimicrobials; (ii) basal diet with carbadox + copper sulfate; (iii) basal diet + 1000 ppm larch extract; or (iv) basal diet + 2000 ppm larch extract. Diets were fed for a 4-week period after weaning. In both trials, the carbadox + copper sulfate group consumed more feed over the 4-week period relative to the other three diet groups (P < 0.05), but did not gain significantly more weight. Faecal shedding of Salmonella spp. was not affected by dietary supplement in either trial, but faecal shedding of Campylobacter spp. was the lowest for the carbadox + copper sulfate diet. In faecal samples collected at the end of each trial, Lactobacillus spp. cell counts for the basal and larch extract diets were nearly 1.0 log(10) g(-1) faeces greater (P < 0.05) than the carbadox + copper sulfate group, whereas the coliforms and Escherichia coli were nearly 1.0 log(10) g(-1) faeces lower (P < 0.05). CONCLUSIONS: Compared to basal fed animals, supplementation with carbadox + copper sulfate significantly altered faecal E. coli, coliform bacteria and Lactobacillus spp. Larch extract has no benefit up to 0.2% of diet in regard to pathogen shedding, whereas carbadox + copper sulfate decreased faecal shedding of Campylobacter spp. SIGNIFICANCE AND IMPACT OF THE STUDY: Current swine management practices in the United States may be beneficial to managing Campylobacter spp. shedding in nursery swine, but also result in significant changes in the resident gastrointestinal microflora.

Population-based epidemiology of Staphylococcus aureus bloodstream infection in Canterbury, New Zealand.

BACKGROUND: Few contemporary reports describe population-based incidence of Staphylcoccus aureus bloodstream infection (SABSI). AIM: To describe longitudinal incidence of SABSI in a region of New Zealand with low MRSA prevalence. METHODS: Blood cultures growing S. aureus were identified from hospital laboratories between 1 July 1998 and 30 June 2006. Record linkage was used to combine information from local and national databases into a single patient event record. Information from the New Zealand census was used to determine regional incidence of disease. An address-based measure of deprivation was used to analyse the relationship between incidence and socioeconomic status. Morbidity data were not collected. RESULTS: 779 patients with SABSI were identified (482/779 (62%) male, 297/779 (38%) female). The crude incidence of S. aureus bacteraemia varied between 18.5-27.3/100 000 per annum. Three of 779 isolates (0.4%) were MRSA. Two hundred and seventy-seven of 776 (36%) patients with complete records had hospital-acquired SABSI. One hundred and forty-one of 778 patients (18%) died within 30 days and 235/778 (30%) died within a year. Proportional hazards survival models significantly associated age, male sex and more than 14 days of hospitalization in the year prior to index culture with adverse outcome. Higher socioeconomic status was associated with lower rates of SABSI (adjusted rate ratio 0.74, 95% confidence interval: 0.56-0.98, P= 0.007 after adjustment for age and sex, and comparing the highest and lowest deprivation quintiles). CONCLUSION: Population factors significantly influence SABSI incidence and survival. Further research is required to determine whether these have the potential to invalidate inter-hospital comparison of SABSI incidence as a measure of health-care quality.

Cytomegalovirus seroprevalence and 'cytomegalovirus-safe' seropositive blood donors.

Cytomegalovirus (CMV) seroprevalence was determined in 9343 first-time New Zealand blood donors between 2003 and 2006. Of 39 960 current seropositive donors the proportion testing seropositive more than 12 months previously was calculated. Overall, seroprevalence declined from 66.1% [95% confidence interval (CI) 64.1-68.1] in 2003 to 60.6% (95% CI 58.5-62.6) in 2006. Nevertheless, these rates are significantly higher than the 47% overall seroprevalence found in a 1988 study. Seroprevalence was higher in females than males and in older than in younger age groups in all four years examined. Ethnicity appeared to be related to seroprevalence with the highest rates found in Pacific Islanders (93.2%) and the lowest in Caucasians (54.8%). At least 38 242/39 960 (95.7%) seropositive donors were found to have seroconverted more than 12 months previously. Recent evidence suggests that such 'remote' seroconverters may pose a much lower risk of transfusion-transmitted CMV infection than recently infected seroconverting, but seronegative, blood donors.

Prevalence of Mycobacterium avium subsp. paratuberculosis in ileocecal lymph nodes and on hides and carcasses from cull cows and fed cattle at commercial beef processing plants in the United States.

Clinical associations between Crohn's disease in humans and Mycobacterium avium subsp. paratuberculosis (MAP) have been suggested but not confirmed. Cattle could be sources for MAP, but little information on MAP prevalence with beef has been reported. Samples of ileocecal lymph nodes and swabs of hides and carcasses from 343 animals at cull cattle slaughtering facilities and 243 animals at fed cattle slaughtering facilities across the United States were analyzed for the presence of MAP. Amplification of genetic sequences detected MAP DNA predominantly on hides and in lymph nodes of samples taken at both types of processing facilities. More than 34% of the cattle at cull cow slaughtering facilities had ileocecal lymph nodes that tested positive for MAP DNA. From these same cattle, hide prevalence was more than twofold greater than the prevalence in ileocecal lymph nodes, suggesting that cross-contamination could be occurring during transport and lairage. The prevalence of MAP DNA decreased during processing, and less than 11% of the carcasses tested positive after interventions in the cull cow processing facilities. Using standard double-decontamination and culture techniques, less than 1% of the postintervention carcasses tested positive for viable MAP at cull cow facilities. In samples from the facilities processing only fed cattle, MAP prevalence of 1% or less was detected for ileocecal lymph node, hide, and carcass samples, and viable MAP was not detected. Based on this study, fed cattle carcasses are unlikely sources of MAP, and carcasses at cull cow plants have only a slight risk for transmitting viable MAP, due to current interventions.