Detection of Bartonella henselae DNA in two dogs with pyogranulomatous lymphadenitis

CASE DESCRIPTION: 1 dog evaluated because of inappetence and lameness of the left hind limb of 1 day's duration and 1 dog evaluated because of inappetence, fever, and lymphadenopathy of 2 weeks' duration. CLINICAL FINDINGS: Histologic examination of excisional biopsy specimens from lymph nodes revealed pyogranulomatous lymphadenitis in both dogs. Quantitative real-time PCR assays detected Bartonella henselae DNA in blood samples and affected lymph node specimens from both dogs. Antibodies against B. henselae were not detected via immunofluorescent antibody testing during active disease in either dog. TREATMENT AND OUTCOME: 1 dog recovered after 6 weeks of treatment with doxycycline (5 mg/kg [2.3 mg/lb], p.o., q 12 h), whereas the other dog recovered after receiving a combination of azithromycin (14.5 mg/kg [6.6 mg/lb], p.o., q 24 h for 21 days), doxycycline (17.3 mg/kg [7.9 mg/lb], p.o., q 24 h for 4 weeks), and immunosuppressive corticosteroid (prednisone [3 mg/kg {1.4 mg/lb}, p.o., q 24 h], tapered by decreasing the daily dose by 25% every 2 weeks) treatment. CLINICAL RELEVANCE: B. henselae is implicated as a possible cause or a cofactor in the development of pyogranulomatous lymphadenitis in dogs. In dogs with pyogranulomatous lymphadenitis, immunofluorescent assays may not detect antibodies against B. henselae. Molecular testing, including PCR assay of affected tissues, may provide an alternative diagnostic method for detection of B. henselae DNA in pyogranulomatous lymph nodes.     

Australindolones,New Aminopyrimidine Substituted Indolone Alkaloids from an Antarctic Tunicate Synoicum sp.

Five new alkaloids have been isolated from the lipophilic extract of the Antarctic tunicate Synoicum sp. Deep-sea specimens of Synoicum sp. were collected during a 2011 cruise of the R/V Nathanial B. Palmer to the southern Scotia Arc, Antarctica. Crude extracts from the invertebrates obtained during the cruise were screened in a zebrafish-based phenotypic assay. The Synoicum sp. extract induced embryonic dysmorphology characterized by axis truncation, leading to the isolation of aminopyrimidine substituted indolone (1–4) and indole (5–12) alkaloids. While the primary bioactivity tracked with previously reported meridianins A–G (5–11), further investigation resulted in the isolation and characterization of australindolones A–D (1–4) and the previously unreported meridianin H (12).     

Experimental infection in calves with a specific subtype of verocytotoxin-producing Escherichia coli O157:H7 of bovine origin

Background

In Sweden, a particular subtype of verocytotoxin-producing Escherichia coli (VTEC) O157:H7, originally defined as being of phage type 4, and carrying two vtx₂ genes, has been found to cause the majority of reported human infections during the past 15 years, including both sporadic cases and outbreaks. One plausible explanation for this could be that this particular subtype is better adapted to colonise cattle, and thereby may be excreted in greater concentrations and for longer periods than other VTEC O157:H7 subtypes.

Methods

In an experimental study, 4 calves were inoculated with 10⁹ colony forming units (cfu) of strain CCUG 53931, representative of the subtype VTEC O157:H7 (PT4;vtx₂;vtx_2c). Two un-inoculated calves were co-housed with the inoculated calves. Initially, the VTEC O157:H7 strain had been isolated from a dairy herd with naturally occurring infection and the farm had previously also been linked to human infection with the same strain. Faecal samples were collected over up to a 2-month period and analysed for VTEC O157 by immuno-magnetic separation (IMS), and IMS positive samples were further analysed by direct plating to elucidate the shedding pattern. Samples were also collected from the pharynx.

Results

All inoculated calves proved culture-positive in faeces within 24 hours after inoculation and the un-inoculated calves similarly on days 1 and 3 post-inoculation. One calf was persistently culture-positive for 43 days; in the remainder, the VTEC O157:H7 count in faeces decreased over the first 2 weeks. All pharyngeal samples were culture-negative for VTEC O157:H7.

Conclusion

This study contributes with information concerning the dynamics of a specific subtype of VTEC O157:H7 colonisation in dairy calves. This subtype, VTEC O157:H7 (PT4;vtx_2;vtx_2c), is frequently isolated from Swedish cattle and has also been found to cause the majority of reported human infections in Sweden during the past 15 years. In most calves, inoculated with a representative strain of this specific subtype, the numbers of shed bacteria declined over the first two weeks. One calf could possibly be classified as a high-shedder, excreting high levels of the bacterium for a prolonged period.     

Review: Endophytic microbes and their potential applications in crop management

Endophytes are microbes (mostly bacteria and fungi) present asymptomatically in plants. Endophytic microbes are often functional in that they may carry nutrients from the soil into plants, modulate plant development, increase stress tolerance of plants, suppress virulence in pathogens, increase disease resistance in plants, and suppress development of competitor plant species. Endophytic microbes have been shown to: (i) obtain nutrients in soils and transfer nutrients to plants in the rhizophagy cycle and other nutrient‐transfer symbioses; (ii) increase plant growth and development; (iii) reduce oxidative stress of hosts; (iv) protect plants from disease; (v) deter feeding by herbivores; and (vi) suppress growth of competitor plant species. Because of the effective functions of endophytic microbes, we suggest that endophytic microbes may significantly reduce use of agrochemicals (fertilizers, fungicides, insecticides, and herbicides) in the cultivation of crop plants. The loss of endophytic microbes from crop plants during domestication and long‐term cultivation could be remedied by transfer of endophytes from wild relatives of crops to crop species. Increasing atmospheric carbon dioxide levels could reduce the efficiency of the rhizophagy cycle due to repression of reactive oxygen used to extract nutrients from microbes in roots. © 2019 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Measuring herding behavior in Border collie—effect of protocol structure on usefulness for selection

From 1989 until 2003, the Swedish Sheepdog Society used a standardized method, Herding Trait Characterization (HTC), to describe herding behavior of individual Border collies for breeding purposes. In the HTC, which existed in 2 consecutive versions, the dog’s herding behavior was described using predefined scales typically consisting of 6 classes within each trait. In total, 1,663 dogs participated in the first version and 951 in the second. The main difference between the versions was the structure of the protocols used to record the traits. In the first version, the scales were designed to describe the intensity in the expression of the measured traits. In the second version, the most desirable behavioral expression was placed in the middle of the scale. Another difference was that in the second version, the judges were given more freedom for their own interpretations, that is, the scales were more subjective. The objective of this study was to examine the quality of each version from a breeding perspective, and to analyze the reasons for possible differences in this respect between them. Heritability estimates for the 17 traits of the earlier version of the HTC ranged from 0.14 to 0.50 (weighted average: 0.30), all significantly different from 0. Corresponding heritabilities for the 19 traits in the later version were substantially lower (0.03-0.41, weighted average: 0.16), 3 of them not being significantly different from 0. Owing to the moderate-to-high heritabilities for the traits measured in the earlier version of the HTC, it would be possible to accomplish effective selection of breeding animals for most of the measured traits. It is plausible that the less neutral and more subjective protocol of the later version is the main cause for the lower heritabilities.     

Do metal contamination and plant species affect microbial abundance and bacterial diversity in the rhizosphere of metallophytes growing in mining areas in a semiarid climate?

Journal of Soils and Sediments - Mining areas are low-quality habitats for macro- and microorganisms’ development, mainly due to the degradation of the soil quality by metal pollution. The...     

Association between radiographic assessment of hip status and subsequent incidence of veterinary care and mortality related to hip dysplasia in insured Swedish dogs

Our objective was to evaluate the association between grading of hip status as assessed by radiographic examination (hip screening) and subsequent incidence of veterinary care and mortality related to hip dysplasia (HD) in five breeds of insured dogs in Sweden. Screening results for hip status from the Swedish Kennel Club and data on veterinary care and mortality from the insurance company Agria were merged based on the registration number of the dog. Dogs of five breeds (Bernese Mountain Dogs, German Shepherds, Golden Retrievers, Labrador Retrievers, and Rottweilers) screened during 1995–2004 and covered by an insurance plan for veterinary care or life at the time of screening were included. The study populations included between 1667 and 10,663 dogs per breed. Breed-specific multivariable Cox proportional-hazards analyses were performed to evaluate the impact of radiographic hip status on time from hip screening to first HD-related veterinary and life claim, respectively. The effects of gender, birth season, and a time-varying covariate of year were also studied. Additional analyses, on the five breeds combined, were performed to investigate the effects of hip status, breed, and the interaction between hip status and breed. The effect of hip status was highly significant (P < 0.001) for both life and veterinary claims related to HD in all five breeds with increased hazard ratio (HR) for deteriorating hip status. Dogs with moderate or severe hip status at screening had a markedly increased hazard of HD-related veterinary care and mortality compared with dogs assessed as free or mild. The time-varying covariate of year showed a significantly higher HR in the last time period for German Shepherds and Labrador Retrievers in the analyses of veterinary claims. In the analyses on all five breeds, German Shepherds had the highest HR for both veterinary care and mortality related to HD, followed by Bernese Mountain Dogs. Golden and Labrador Retrievers had the lowest HR. The effect of hip status on the hazard was the same irrespective of breed. However, as a consequence of differences between breeds in overall risk, the predictive ability of screening results for subsequent incidence of HD-related problems for individual dogs was breed-dependent. Based on the strong association between radiographic hip status and incidence of HD-related veterinary care and mortality, and the previously reported moderate heritability of hip status, we conclude that selection based on screening results for hip status can be expected to reduce the risk of HD-related clinical problems.