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The periodicity of life‐cycle events (phenology) modulates host availability to pathogens in a repeatable pattern. The effects of sexual differences in host phenology have been little explored in wildlife epidemiological studies. A recent series of ranavirosis outbreaks led to serious declines of Boscas' newt populations at Serra da Estrela (Portugal). The peculiar phenology of this species, in which a large number of females remain in the aquatic habitat after the breeding season, turns it into a suitable model to test how sex‐biased mortality can affect host population persistence in the context of infectious diseases. We investigated how the phenology of Bosca's newt (i.e. biased number of females) mediated the impact of Ranavirus. We then evaluated the risk of extinction of the population under different scenarios of sex‐biased mortality using a population viability analysis. Two newt populations (one subject to yearly outbreaks and a comparative site where outbreaks have not been recorded) were tracked for trends over time following emergence of ranaviral disease, allowing us to assess the differential impact of the disease on both sexes. In addition to a significant decline in abundance of adult newts, our data suggest that phenology can affect disease dynamics indirectly, leading to reduction in females and a reversal of the sex ratio of the breeding population. Our models suggest that female‐biased mortality does not exacerbate Ranavirus‐driven population declines in the short‐term, but is likely to have a deleterious impact during the recovery process once the lethal effect of disease is removed from the system. [ABSTRACT FROM AUTHOR]

Context Swine dysentery in Europe is typically attributed to Brachyspira hyodysenteriae; however, a new type of Brachyspira infection has recently been described. Outbreaks of mucohaemorrhagic diarrhoea caused by strongly haemolytic Brachyspira strains inconsistent with B hyodysenteriae have been reported in the USA and Canada. These isolates have been provisionally named as 'Brachyspira hampsonii?. Main conclusion This case report describes the first case of B hampsonii infection in European pigs. It also indicates that the diagnosis of infections caused by new, emerging Brachyspira species is not self-evident and that a combination of microbial culture and PCR is recommended, alongside more extensive genotyping if necessary. Approach In a routine quarantine monitoring protocol, two gilts underwent postmortem examination. Microbial culture from the colonic content and from faecal samples revealed the presence of strongly haemolytic, ring-phenomenon- positive spirochaetes indicative for B hyodysenteriae; however, this could not be confirmed by PCR. Further characterisation of the isolates was performed by phenotypic characterisation, species-specific PCRs, sequencing of nox and 16S rRNA genes and multilocus sequence typing. Sequences of the partial nox and 16S rRNA genes were compared with sequences of other Brachyspira strains and species and a phylogenetic tree based on the alignment of the nox gene was constructed. Additionally, PCRs were performed for the haemolysis-related genes tlyA, hlyA and hlyA-ACP. Results The results indicate that the isolate was B hampsonii clade I. All isolates contained the haemolysis-associated genes hlyA, tlyA and ACP. This may explain the strong haemolysis displayed by these isolates. Interpretation Although experimentally B hampsonii strain 30599, which belongs to clade I, can induce severe clinical signs, the signs in this case were rather mild. This could be due to differences in pathogenic potential between strains or be related to Brachyspira colitis being a multifactorial disease. Environmental or nutritional factors may alter the severity of clinical signs. Significance of findings This is the first time that B hampsonii isolates porcine origin have been described in Europe. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate whether T-2 toxin, a potent Fusarium mycotoxin, affects the oral absorption of the antibiotic chlortetracycline in pigs. Animals were allocated to blank feed without T-2 toxin (controls), feed containing 111 μg T-2/kg feed, T-2-contaminated feed supplemented with a yeast-derived feed additive, or blank feed supplemented solely with the feed additive, respectively. After 21 days, an intragastric bolus of chlortetracycline was given to assess potential alterations in the pharmacokinetics of this commonly used antibiotic. A significantly higher area under the plasma concentration-time curve and maximal plasma concentration of chlortetracycline was observed after intake of T-2-contaminated feed compared with control. Thus, exposure to T-2-contaminated feed can influence the oral bioavailability of chlortetracycline. This effect could have consequences for the withdrawal time of the drug and the occurrence of undesirable residues in edible tissues. [ABSTRACT FROM AUTHOR]

Background There is increased proportional mortality from Parkinson's disease amongst livestock farmers. The hypokinesia of Parkinson's disease has been linked to Helicobacter pylori. H. suis is the most common zoonotic helicobacter in man. Aim To compare the frequency of H. suis, relative to H. pylori, in gastric biopsies of patients with idiopathic parkinsonism ( IP) and controls from gastroenterology services. Methods DNA extracts, archived at a Helicobacter Reference Laboratory, from IP patient and gastroenterology service biopsies were examined anonymously for H. suis, using species-specific RT- PCR. Results Relative risk of having H. suis in 60 IP patients compared with 256 controls was 10 times greater than that of having H. pylori. In patients with IP and controls, respectively, frequencies of H. suis were 27 (exact binomial 95% C.I. 15, 38) and 2 (0, 3)%, and of H. pylori, 28 (17, 40) and 16 (12, 21)%. Excess of H. suis in IP held when only the antral or corporal biopsy was considered. Of 16 IP patients with H. suis, 11 were from 19 with proven H. pylori eradication, 3 from 17 pre- H. pylori eradication, 2 from 24 H. pylori culture/ PCR-negative. Frequency was different between groups ( P = 0.001), greatest where H. pylori had been eradicated. Even without known exposure to anti- H. pylori therapy, H. suis was more frequent in IP patients (5/41) than in controls (1/155) ( P = 0.002). Partial multilocus sequence typing confirmed that strains from IP patients (6) and control (1) differed from RT- PCR standard strain. Conclusions Greater frequency of H. suis in idiopathic parkinsonism appears exaggerated following H. pylori eradication. Multilocus sequence testing comparison with porcine strains may clarify whether transmission is from pigs/porcine products or of human-adapted, H. suis-like, bacteria. [ABSTRACT FROM AUTHOR]

A feeding trial was conducted to evaluate the effects of mannanoligosaccharides (MOS) on nutrient digestibility, intestinal pH, gut morphology and faecal bacteriology of pigeons, as model for birds without functional caeca. Sixteen adult pigeons ( Columba livia domestica) were randomly allotted to either an extruded pellet diet with or without 0.4% MOS. After an adaptation period of 24 days, excreta were collected during 4 days. Apparent nutrient digestibility coefficients were determined using total collection method. Further, excreta pH was measured and percentage of uric acid determined. Fresh excreta were cultured for measurement of colony-forming units for Escherichia coli. At the end, the gastrointestinal tract (GIT) was excised and pH measurements performed on the separate GIT sections. Finally, pancreas, liver, gizzard and abdominal fat pad were weighed, and standardised segments of duodenum and jejunum were removed for microscopic measurement of crypt depth, villus height and muscularis thickness. Feed intake and water intake were similar between control diet and MOS diet. Intestinal pH was unaffected by MOS supplementation; however, excreta pH was significantly lower in pigeons on the MOS diet. Although nutrient digestibility was similar between treatments, uric acid content of excreta was significantly higher in the MOS group in relation to the control group. Further, duodenal crypt depth, villus height and muscularis thickness, as well as jejunal muscularis thickness were all significantly reduced by MOS supplementation. No effect of MOS supplementation was seen on the counts of E. coli. Furthermore, despite marked differences on both GIT morphology and uric acid content of excreta, apparent digestibility coefficients, and organ weights, were similar between treatments. It is suggested that the MOS-induced changes on gut morphology and the reduced excreta pH reflect a reduced bacterial challenge in the intestine of pigeons. Supplementation of MOS, therefore, has potential as prebiotic strategy in birds without functional caeca. [ABSTRACT FROM AUTHOR]

The effect of starch gelatinisation degree in extruded feed on intestinal morphology, intestinal pH and faecal bacteriology was investigated in pigeons. Extruded complete pigeon diets would offer the principle advantage of providing equilibrated nutrients and energy, but factors such as starch gelatinisation require investigation before these diets are offered as main dietary items to pigeons. Birds were fed two diets with equal ingredient composition and nutrient content, but with a different degree of starch gelatinisation resulting from altered extrusion processing (high gelatinisation degree (HG) with 73.6% gelatinisation vs. low gelatinisation degree (LG) with 53.1% gelatinisation). Feed intake and weight gain changes were measured weekly. Blood samples were collected at day 28 and analysed for non-esterified fatty acids, lactate dehydrogenase and glucose. The pH values for fresh excreta were measured; thereafter fresh excreta were collected and cultured for measurement of colony-forming units for bacterial classes. At the end, morphological measurements were examined and the pH values throughout the gastrointestinal tract were recorded. Liver, pancreas and abdominal fat were weighed. There was a tendency (p = 0.07) towards higher numbers of Escherichia coli in the excreta of the LG group compared with those in the HG group. No dietary treatment effects were noted on the number of Lactobacillus sp. in the excreta. In proximal parts of the intestine, LG revealed a significantly lower pH than HG. Villus height and crypt depth were not affected by dietary treatment, but the duodenum muscularis thickness, liver weight and pancreas weight were significantly lower in the LG than that in HG group. This trial demonstrated that the lower level of starch gelatinisation degree of extruded feed leads to acidification of the proximal gut and altered gut morphology in pigeons. Hence, extruded pigeon diets should preferably contain low-gelatinised starch instead of high-gelatinised starch. In addition, future research must focus on the effects of starch gelatinisation on the correlation between the intestinal pH, microflora content and intestinal morphology. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine whether a hydrolysable tannin extract of sweet chestnut wood (Globatan®) has an inhibitory effect on Salmonella Typhimurium survival both in vitro and in vivo in pigs. In a first experiment, the minimal inhibitory concentration of Globatan® on 57 Salmonella Typhimurium isolates was determined. For all isolates, an MIC of 160–320 μg/ml was found. The second in vitro study revealed that Salmonella growth was strongly reduced using Globatan® concentrations of 25–50 μg/ml and nearly completely inhibited at a concentration of 100 μg/ml Globatan®. In an in vivo trial, two groups of six piglets, each group receiving feed with or without the addition of Globatan® (3 g/kg), were orally inoculated with 107 colony forming units of a Salmonella Typhimurium strain. Globatan® had no effect on faecal excretion of Salmonella, and no differences in colonization of the intestines and internal organs were demonstrated in pigs euthanized at 4 days post-inoculation. In conclusion, the hydrolysable tannin extract used in this study showed strong action against Salmonella Typhimurium in vitro but not in vivo. [ABSTRACT FROM AUTHOR]

Summary Reasons for performing study: Standard methods for culturing equine synovial fluid (SF) are often unrewarding. Evidence-based information on the relative efficiency of different systems used for optimisation of isolation of microorganisms from equine SF is lacking. Objectives: To compare the results of different culture systems performed in parallel on SF samples from horses clinically diagnosed with synovial sepsis. Methods: Synovial fluid specimens were collected between February 2007 and October 2008 from all horses admitted to a referral hospital that were clinically diagnosed with synovial sepsis and from control horses. Synovial fluid samples were cultured in parallel by: 1) direct agar culture (DA); agar culture after: 2) lysis-centrifugation pretreatment (LC); 3) conventional enrichment (CE); 4) combined LC/CE; or 5) blood culture medium enrichment using an automated system (BACTEC 9050). Results: Ninety SF samples from 82 horses were included, together with 40 control samples. Seventy-one of 90 samples (79%) were culture-positive by using blood culture medium enrichment (BACTEC), which was significantly higher compared to all other methods. BACTEC enrichment was never negative while any of the other methods was positive. Although agar culture following LC and/or CE resulted in a slightly higher number of positive samples compared to DA, this difference was not significant. All control samples were culture negative by the 5 different techniques. Although the majority of samples containing isolates recovered without enrichment, culture results after BACTEC enrichment were available on the same day as for agar culture with or without LC (19/23 samples), while CE postponed recovery by at least one day in 20/23 samples. Conclusion: Blood culture medium enrichment is superior to other techniques for isolation of bacteria from SF of horses. The use of an automated system allows enrichment without substantially postponing recovery of microorganisms. Potential relevance: The efficient and fast isolation of microorganisms from infected SF by the BACTEC system allows for rapid susceptibility testing and a more appropriate antibiotic treatment. [ABSTRACT FROM AUTHOR]

In all European Union member states, Salmonella monitoring in poultry flocks is obligatory. In these monitoring programmes, a limited number of pooled faeces and/or dust samples are collected to determine whether Salmonella is present in the flocks or not. Whether these limited sampling protocols are sufficiently sensitive to detect expected low within-flock prevalences of an intermittently shed pathogen is not yet clear. In this study, a comparison is made between different sampling procedures for the assessment of the between- and within-flock prevalence of Salmonella in laying hens. In total, 19 farms were sampled. Using a comparable sampling methodology as in the official surveillance programmes, Salmonella could not be detected in any of the flocks. After transportation of the hens to the laboratory and subsequent analysis of cloacal swabs and caecal contents, Salmonella Enteritidis was detected in laying hens from five of 19 farms. The observed within-flock prevalence ranged from 1% to 14%. Based on the results of this study, it can be expected that, depending on the sampling procedure, different estimates of the prevalence of Salmonella can be obtained and the proportion of Salmonella infected flocks is underestimated based on the results of the official monitoring programme. [ABSTRACT FROM AUTHOR]

Salmonella Enteritidis is still a major cause of human food borne infections and can be associated with the consumption of meat and chicken eggs. It is the world’s most common cause of salmonellosis in part because it has the ability to colonize the oviduct and contaminate eggs. It was shown that when stored at room temperature, S. Enteritidis bacteria can multiply extensively in contaminated eggs. Using the in vivo expression technology, it was shown that the rfbH gene, involved in lipopolysaccharide O-antigen synthesis, is transcriptionally induced during growth in whole eggs at room temperature. A S. Enteritidis ΔrfbH strain was unable to multiply in eggs at room temperature and did not survive in egg white at 42°C. The attenuation was most likely caused by an increased susceptibility of the ΔrfbH mutant to yet undefined antibacterial components of the egg albumen. [ABSTRACT FROM AUTHOR]

A collection of 102 coagulase-negative staphylococci (CNS), isolated from cases of subclinical and clinical bovine mastitis and belonging to 10 different species, were screened by PCR for the presence of genes encoding enterotoxins and enterotoxin-like toxins (sea, seb, sec, sed, see, seg, seh, sei, sej, selk, sell, selm, seln, selo, selp, selq and selu), toxic shock syndrome toxin-1 (tst), and exfoliative toxins A and B (eta and etb). No toxin gene sequences were amplified from any of the isolates, indicating that superantigens encoded by genes detectable by the PCR tests used were not involved in the development of subclinical and clinical mastitis in cattle infected with the CNS isolates tested. [ABSTRACT FROM AUTHOR]

Inclusion body disease, a fatal disorder in Boidae, is reviewed, and three cases in boa constrictors, the first reported cases in Belgium, are described. The snakes showed nervous signs, and numerous eosinophilic intracytoplasmic inclusions, which are considered to be characteristic of the disease, were found in the liver and pancreas. The disease is suspected to be caused by a retrovirus, but transmission electron microscopic examinations of several tissues from one of the snakes did not reveal particles with a typical retroviral morphology. [ABSTRACT FROM AUTHOR]

Flavobacterium psychrophilum is the causative agent of bacterial cold water disease and rainbow trout fry syndrome, disease entities responsible for substantial economic losses in salmonid aquaculture. Problems associated with epizootics include high mortality rate, increased susceptibility to other diseases, high labour costs of treatment and the enormous expenditure on chemotherapy. Despite the increasing significance of the disease, the pathogenesis of F. psychrophilum infections has only been partially elucidated, hampering the development of preventive measures to efficiently combat this disease condition. This literature review discusses the agent and the disease it causes, with emphasis on the bacterium–host interactions. [ABSTRACT FROM AUTHOR]

Amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd), is associated with declines in ~500 amphibian species globally. Decades after initial disease outbreaks, the trajectory of impacted species varies substantially; while some species continue to decline, there are instances of natural recovery, such as the whistling tree frog, Litoria verreauxii, in south‐eastern Australia. The decline and subsequent recovery of this species have been quantified through repeated surveys of historically occupied sites over the past 30 years; however, the underlying mechanisms driving this recovery remain unknown. In this study, we investigate the potential factors facilitating the recovery of L. verreauxii by examining Bd prevalence and intensity in both adults and tadpoles. Specifically, we addressed the following hypotheses: (1) Bd prevalence in tadpoles would be lower compared to adults at the same breeding sites, (2) Bd prevalence in tadpoles would decrease over the spring breeding season due to the increasing availability of warm water microhabitats where tadpoles could potentially avoid or clear Bd infections and (3) there would be a negative correlation between Bd prevalence in tadpoles and the abundance and diversity of microfauna, which may consume Bd zoospores. Our findings indicate that tadpole infection prevalence remained consistently low at 1.36% (95% CI: 0.6–2.47%) throughout our spring sampling period, across different developmental stages. Adults had moderate to high prevalence within the same ponds at 50.53% (95% CI: 43.19–57.84%). No effect of temperature or microfauna diversity and abundance was apparent. While the mechanisms driving the recovery of this species remain unknown, low infection prevalence in tadpoles is likely a key component to the species' recovery. Our results emphasize the need for comprehensive investigations in Bd dynamics across all life history stages within recovering and declining amphibian species. [ABSTRACT FROM AUTHOR]

Summary Reasons for performing study: A novel urease-negative Helicobacter species has been isolated from faecal samples of clinically healthy horses, but no information is available about the main sites of colonisation in the equine gastrointestinal tract nor is the pathogenic potential of this microorganism known. An experimental infection in horses was therefore carried out. Methods: Four horses were infected with H. equorum strain CCUG 52199T and subjected to euthanasia at 10 (n = 2) and 30 days (n = 2) post inoculation. A fifth animal was inoculated with phosphate buffered saline and used as control. Gastrointestinal samples were examined histologically and bacteriologically. These samples, as well as faecal material collected at regular intervals, were also subjected to PCR analysis. Results: All horses remained clinically healthy and no specific macroscopic lesions were identified, nor were there any microscopic changes. H. equorum-DNA was detected in the faeces during the whole experiment in all infected animals but not in the negative control. Sites of colonisation were caecum, colon and rectum. Conclusions: H. equorum is able to colonise the equine lower bowel and is excreted in faeces without apparent pathology. No association between the presence of the organism and gastrointestinal disease was demonstrated. [ABSTRACT FROM AUTHOR]

In this article, the author discusses impact of chytridiomycosis, which is caused by the chytrid fungi Batrachochytrium dendrobatidis (Bd) and Batrachochytrium salamandrivorans (Bsal), and leading global amphibian declines. it mentions the use of applications such as vaccination, disinfection, and bioaugmentation for mitigation of the impact of amphibian chytridiomycosis.

The article discusses the study on Helicobacter pullorum (H pullorum) which was found in the feces of a diarrheic psittacine bird. Helicobacter pullorum is an enterohepatic Helicobacter species which has been separated from the ceaca and liver of broilers and laying hens and the feces of human beings. It has been suggested that H pullorum caused chronic diseases in human beings and connected with vibrioic hepatitis in laying hens and such case is first time in psittacine birds.

Focuses on the association of chytrid fungus Batrachochytrium dendrobatidis with the decline of amphibian populations. Habitats of amphibians with massive deaths; Diagnosis of chytridiomycosis; Concern on anuran species compared to urodelan casualties.

This study describes a non-Helicobacter (H.) pylori Helicobacter (NHPH) infection in a pig veterinarian. The patient suffered from reflux esophagitis and general dyspeptic symptoms and was referred to the hospital for upper gastrointestinal endoscopy. Histologic examination of corpus and antrum biopsies revealed a chronic gastritis. Large spiral-shaped non-H. pylori helicobacters could be visualized and were identified as H. suis by PCR. The patient was treated with a triple therapy, consisting of amoxicillin, clarithromycin, and pantoprazole for 10 days. Successful eradication was confirmed after a follow-up gastrointestinal endoscopy and PCR 10 weeks after treatment. A mild chronic gastritis was, however, still observed at this point in time. This case report associates porcine H. suis strains with gastric disease in humans, thus emphasizing the zoonotic importance of H. suis bacteria from pigs., (© 2013 John Wiley & Sons Ltd.)

The last year has seen an interesting and important collection of evidence presented in the field of the "other" than Helicobacter pylori Helicobacters. Associations with adult ulcerative colitis and biliary/hepatic disease have been described. New insights into the immune response and subsequent pathogenesis associated with infection have also been published. Genomic advances include description of new and unique species and the complete genome description for both Helicobacter felis and Helicobacter suis. Molecular studies have also elucidated the mechanism of action of some functional components of these organisms., (© 2011 Blackwell Publishing Ltd.)

Background: The Mongolian gerbil model is often used to investigate the interactions between different gastric Helicobacter species and the gastric tissue. A preliminary screening of a gerbil population intended for use in Helicobacter suis infection studies revealed a natural yeast infection in the stomach of these animals. After identification, we have investigated the effect of the gastric yeast infection on the outcome of an experimental H. suis infection in Mongolian gerbils., Materials and Methods: Yeast cells were isolated from the stomachs of Mongolian gerbils. Identification was done by Internally Transcribed rRNA Spacer 2 Region PCR fragment length analysis. To investigate a possible pathologic role of this yeast, Mongolian gerbils were infected experimentally with this yeast. Co-infection with the newly isolated H. suis was performed to investigate possible interactions between both micro-organisms., Results: Kazachstania heterogenica was found colonizing the stomach of Mongolian gerbils, mainly in the antrum. Few pathologic changes were seen in the stomachs of infected animals. Experimental co-infection of gerbils with this yeast and the newly isolated H. suis showed a significant increase in inflammation in animals infected with both micro-organisms compared to animals infected only with H. suis., Conclusions: K. heterogenica colonizes the stomach of Mongolian gerbils in exactly the same regions as gastric Helicobacter species. The uncontrolled presence of this yeast in the gerbil stomach can lead to an overestimation of the inflammation caused by Helicobacter in this animal model.