Molecular and Serological Detection of Vector-Borne Pathogens Responsible for Equine Piroplasmosis in Europe between 2008 and 2021

Equine piroplasmosis (EP) is caused by Theileria (T.) equi and/or Babesia (B.) caballi. The aim was to assess the percentage of positive test results for EP in horses in Europe and to identify risk factors for pathogen contact/infection. This study included results from PCR and competitive enzyme-linked immunosorbent assay testing requested by European veterinarians between 2008 and 2021. Binary bivariate logistic regression was used to analyze risk factors. A total of 4060 horses were included. PCR testing was positive in 9.7% (154/1589), serology for T. equi in 15.2% (393/2591) and for B. caballi in 6.8% (175/2578). The odds of positive serology increased by 6.8% (B. caballi, p = 0.008) and 9.5% (T. equi, p < 0.001) each year. Regionality had a statistically significant impact on PCR (Eastern p = 0.047/OR = 1.605; Southern p = 0.029/OR = 1.451; Central p = 0.007/OR = 0.617) and serological testing for T. equi (Southern p < 0.001/OR = 2.521; Central p < 0.001/OR = 0.537; Northern p = 0.003/OR = 0.462), as well as breeds on seroprevalence of B. caballi (heavy horses: p = 0.016/OR = 2.239) and T. equi (ponies: p = 0.007/OR = 0.340; warmbloods: p = 0.025/OR = 1.602). In conclusion, there was a significant geographical impact on the results of PCR and serology, consistent with known vector habitats. The rising numbers of horses tested serologically positive highlights the importance of surveillance.

Outcome of parasitological examinations in dogs in Germany: a retrospective survey

Dog faecal samples examined from January 2019 to December 2019 were retrospectively analysed for frequency of endoparasites. The examinations were performed with several different methods: 29,219 samples were examined by flotation method and sodium acetate-acetic acid-formalin concentration (SAFC) technique, 1,330 samples by Baermann-Wetzel migration technique, 12,221 samples using a Giardia coproantigen enzyme-linked-immunosorbent assay (ELISA), 1,180 samples using a Cryptosporidium coproantigen ELISA, 1,671 samples by polymerase chain reaction (PCR) testing for Giardia duodenalis and 447 samples by PCR testing for Cryptosporidium spp.. A total of 7.1% of the samples were positive for parasites in the microscopical examination using the flotation method and SAFC technique. The parasites found included Cystoisospora spp. (2.8%), Giardia duodenalis (2.3%), Ancylostomatidae (1.8%), Toxocara canis (1.6%), Trichuris vulpis (0.7%), Toxascaris leonina (0.5%), Capillaria spp. (0.2%), Angiostrongylus vasorum (0.2%), Crenosoma vulpis (0.1%), Taeniidae (0.1%), Sarcocystis spp. (0.03%), Dipylidium caninum (0.01%), Diphyllobothrium latum (< 0.01%), Spirurida (< 0.01%) and Opisthorchiidae (< 0.01%). Using the Baermann-Wetzel migration technique, Angiostrongylus vasorum was found in 0.75% and Crenosoma vulpis in 0.3% of the samples. ELISAs for Giardia duodenalis and Cryptosporidium spp. revealed 13.9% and 1.0% positive faecal samples, and Giardia duodenalis and Cryptosporidium spp. PCRs 19.4% and 2.0%, respectively. Dogs in the first year of life were more frequently infected with parasites than older animals. In the microscopic examination using flotation method and SAFC technique, the significantly highest detection rates were found in dogs up to six months of age (p < 0.001).

Intervention with impact: Reduced isolation of methicillin-resistant Staphylococcus pseudintermedius from dogs following the introduction of antimicrobial prescribing legislation in Germany

BACKGROUND

Legislation was introduced in Germany in 2018, requiring bacterial culture and antimicrobial susceptibility testing before the prescription of fluoroquinolones and third-generation cephalosporins to dogs. We hypothesised that, following this intervention, the number of clinical samples testing positive for methicillin-resistant Staphylococcus pseudintermedius (MRSP) would reduce.

METHODS

Reports of S. pseudintermedius isolated from canine clinical samples by three German veterinary diagnostic microbiology laboratories during the 38 months before the introduction of the legislation and the 46 months after were compared. Bacterial identification was performed by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry, and antimicrobial susceptibility testing followed recognised recommendations but with changes during the study period.

RESULTS

Among a total of 120,571 S. pseudintermedius isolates, MRSP accounted for 7.1% overall. Following the legislative intervention, monthly submissions yielding S. pseudintermedius increased at all three laboratories. The MRSP percentage was lower in the period after the intervention in two of the three laboratories (p < 0.001); in the third laboratory, there was no change between periods, but a year-on-year reduction in MRSP percentages occurred after the intervention (p = 0.0004).

LIMITATIONS

Changing susceptibility testing methods limited the direct comparison of resistance patterns among laboratories.

CONCLUSION

The reduction in MRSP in canine clinical samples following the introduction of this legislation suggests a positive impact of compulsory laboratory testing on reducing antimicrobial resistance.

Clinical Signs in 166 Beagles with Different Genotypes of Lafora

Lafora disease (LD) is a genetic disease affecting beagles, resulting in seizures in combination with other signs. The aim of this study was to describe the clinical signs of LD in beagles with different NHLRC1 genotypes. One hundred and sixty-six beagles were tested for an NHLRC1 gene defect: L/L (n = 67), N/L (n = 32), N/N (n = 67). Owners were asked to participate in a survey about the clinical signs of LD in their dogs. These were recorded for the three possible genotypes in the two age groups, <6 years and ≥6 years. In all genotypes, nearly all the signs of LD were described. In the age group ≥ 6 years, however, they were significantly more frequent in beagles with the L/L genotype. If the following three clinical signs occur together in a beagle ≥ 6 years-jerking of the head, photosensitivity and forgetting things he/she used to be able to do-98.2% of these dogs are correctly assigned to the L/L genotype. If one or two of these signs are missing, the correct classification decreases to 92.1% and 13.2%, respectively. Only the combination of certain signs truly indicates the L/L genotype. Yet, for many dogs, only genetic testing will provide confirmation of the disease.

A comparative survey of the influence of small self-cleaving ribozymes on gene expression in human cell culture

Self-cleaving ribozymes are versatile tools for synthetic biologists when it comes to controlling gene expression. Up to date, 12 different classes are known, and over the past decades more and more details about their structure, cleavage mechanisms and natural environments have been uncovered. However, when these motifs are applied to mammalian gene expression constructs, the outcome can often be unexpected. A variety of factors, such as surrounding sequences and positioning of the ribozyme influences the activity and hence performance of catalytic RNAs. While some information about the efficiency of individual ribozymes (each tested in specific contexts) is known, general trends obtained from standardized, comparable experiments are lacking, complicating decisions such as which ribozyme to choose and where to insert it into the target mRNA. In many cases, application-specific optimization is required, which can be very laborious. Here, we systematically compared different classes of ribozymes within the 3'-UTR of a given reporter gene. We then examined position-dependent effects of the best-performing ribozymes. Moreover, we tested additional variants of already widely used hammerhead ribozymes originating from various organisms. We were able to identify functional structures suited for aptazyme design and generated highly efficient hammerhead ribozyme variants originating from the human genome. The present dataset will aide decisions about how to apply ribozymes for affecting gene expression as well as for developing ribozyme-based switches for controlling gene expression in human cells.

Hemophilia A in a litter of Border Collies caused by a one base pair deletion in the F8 gene

In dogs, hemophilia A is known to affect different breeds. This is a case report describing hemophilia A in a litter of Border Collies. A privately owned bitch and her puppies (n = 7) were presented to the referring veterinarian after acute hematoma formation in the male offspring (n = 3) following microchip implantation. Global coagulation testing, as well as determination of factor VIII and IX activity, were carried out. Based on the results, factor VIII deficiency was suspected. Two of the affected male puppies were euthanized within a few days. Genetic testing of the mother and the surviving male puppy resulted in the description of a deletion in exon 14 of the F8 gene. This c.3206delA variant leads to a frameshift in amino acid sequence and a premature stop codon (p.Asn1069IlefsTer7). The detection of the mutation and consequent testing of related dogs revealed that the deletion most likely had occurred spontaneously in the mother and had been transmitted to several of her offspring in different litters. Identified carriers were taken out of the breeding scheme. It is concluded that genetic testing in the context of suspected genetic disease can lead to preventive measures, including timely exclusion of carriers from breeding.

Gait is not Affected by Hemispherotomy-Case Report from Two Children

In children with therapy refractory epilepsy, the functional disconnection of one hemisphere (hemispherotomy) may be considered as a treatment option. The visual field defects and hand function effects associated with the procedure have been extensively studied. However, the effect of the hemispherotomy on gait pattern has thus far only been analyzed qualitatively, and there is limited quantitative data. At the Children's Hospital, we regularly perform standardized quantitative gait analysis studies and care for children with complex epilepsies. During the standard routine of care for two children with structural therapy refractory epilepsy, gait analysis was performed prior to and after hemispherotomy. Both patients had prenatal ischemic brain lesions, had developed severe epilepsy during the first 3 years of life, and were treated with the hemispherotomy at about 7 years of age. Interestingly, one patient did not show any changes in gait pattern, while for the other patient, differences could be observed by means of three-dimensional gait analysis. However, greater deviations to controls postoperatively may also be related to day-to-day variability.

Mental representation of equivalence and order

With mental models based on relational information, the present research shows that the semantics expressed by the relation can determine the structural properties of the constructed model. In particular, we demonstrate a reversal of the classical, well-replicated symbolic distance effect (SDE), as a function of relational semantics. The classical SDE shows that responses are more accurate, and faster, the wider the distance between queried elements on a mentally constructed rank order. We replicate this effect in a study using a relation that expresses a rank hierarchy ("older than," Experiment 4). In contrast, we obtain a clear reversal of the same effect for accuracy data when the relation expresses a number of equivalence classes ("is from the same city," Experiments 1-3). In Experiment 3, we find clear evidence of a reversed SDE for accuracy and latency in the above standard condition, and flat curves of means, across pair distances, for accuracy and latency in a condition that makes equivalence classes salient from the beginning. We discuss these findings in the context of a process model of equivalence class formation based on learned piecemeal information.

Molecular survey on vector-borne pathogens in clinically healthy stray cats in Zaragoza (Spain)

BACKGROUND

In Europe, feline vector-borne infections are gaining importance because of the changing climate, expanding habitats of potential vectors and expanding pathogen reservoirs. The main objective of this study was to assess the prevalence of vector-borne pathogens (VBPs) in stray cats in Zaragoza, Spain, and to investigate potential risk factors for infection, including feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV).

METHODS

Blood samples from stray cats presented to the veterinary faculty in Zaragoza between February 2020 and 2022 were tested by polymerase chain reaction (PCR) for the presence of Anaplasma phagocytophilum, Anaplasma platys, Bartonella henselae, Ehrlichia canis, Rickettsia spp., haemotropic Mycoplasma spp., Hepatozoon spp., Leishmania infantum, piroplasms and microfilariae at the LABOKLIN laboratory. The cats were also tested for FeLV and FIV by PCR.

RESULTS

Nearly half of the cats (158/332, 47.6%) were positive for at least one VBP. Hepatozoon spp. were detected in 25.6%, haemotropic Mycoplasma spp. in 22.9%, B. henselae in 9.3% and L. infantum in 2.1% of the cats. Male sex had a statistically significant association with test results for haemotropic Mycoplasma spp. (odds ratio 1.38 [1.21;1.57]); regionality with Hepatozoon spp., B. henseale and FIV; and seasonality with Hepatozoon spp., haemotropic Mycoplasma spp., L. infantum and FeLV (P ≤ 0.05 each). A strong positive correlation was reported for the amount of rainfall and the number of cats that tested positive for Hepatozoon spp. (ρ = 753, P = 0.05). None of the cats tested positive for A. phagocytophilum, A. platys, E. canis, Rickettsia spp., piroplasms, or microfilariae. Co-infections with multiple VBPs were detected in 56 out of 332 cats (16.9%). Thirty-one of the 332 cats included in the study (9.3%) tested positive for FeLV (6.9%) and for FIV (3.6%). In 20/31 cats (64.5%) that tested positive for FeLV/FIV, coinfections with VBP were detected (P = 0.048, OR 2.15 [0.99; 4.64]).

CONCLUSIONS

VBPs were frequently detected in stray cats in Zaragoza. In particular, regionality and seasonality had a statistically significant association with PCR results for most VBPs included in the study.

Molecular detection of Babesia spp. in dogs in Germany (2007-2020) and identification of potential risk factors for infection

BACKGROUND

In Europe, canine babesiosis is most frequently caused by Babesia canis and Babesia vogeli, and occasionally by Babesia gibsoni.. In Germany, B. canis is recognized as endemic. The aims of this study were to assess how often Babesia spp. infections were diagnosed in a commercial laboratory in samples from dogs from Germany, and to evaluate potential risk factors for infection.

METHODS

The database of the LABOKLIN laboratory was screened for Babesia spp.-positive polymerase chain reaction (PCR) tests for dogs for the period January 2007-December 2020. Sequencing was performed for positive tests from 2018 and 2019. Binary logistic regression analysis was performed to determine the effects of sex, season, and year of testing. Questionnaires were sent to the submitting veterinarians to obtain information on travel abroad, tick infestation, and ectoparasite prophylaxis of the respective dogs. Fisher's exact test was used to calculate statistical significance and P < 0.05 was considered statistically significant.

RESULTS

In total, 659 out of 20,914 dogs (3.2%) tested positive for Babesia spp. by PCR. Of 172 sequenced samples, B. canis was identified in 156, B. vogeli in nine, B. gibsoni in five, and B. vulpes in two. Season had a statistically significant impact on test results when summer/winter (1.6% tested positive) was compared to spring/autumn (4.7%), with peaks in April (5.2%) and October (7.4%) [P < 0.001, odds ratio (OR) = 3.16]. Sex (male 3.5%, female 2.8%; P = 0.012, OR = 1.49) and age (< 7 years old 4.0%, ≥ 7 years old 2.3%; P < 0.001, OR = 1.76) of the tested dogs also had a statistically significant effect. A statistically significant impact was demonstrated for observed tick attachment (P < 0.001, OR = 7.62) and lack of ectoparasite prophylaxis (P = 0.001, OR = 3.03). The frequency of positive Babesia spp. tests did not significantly differ between the 659 dogs that had never left Germany and the 1506 dogs with known stays abroad (P = 0.088).

CONCLUSIONS

The possibility of canine infection with B. canis needs to be especially taken into consideration in spring and autumn in Germany as the activity of the tick Dermacentor reticulatus, a potential vector for canine babesiosis, is highest in these seasons. Travel and importation of dogs are considered major factors associated with canine babesiosis in Germany. However, autochthonous Babesia spp. infections also occur in a considerable number of dogs in Germany.

Fibroblast Growth Factor-23 (FGF-23) in Dogs-Reference Interval and Correlation with Hematological and Biochemical Parameters

Fibroblast growth factor-23 (FGF-23) is a phosphaturic hormone used to monitor chronic kidney disease (CKD) in humans. The aims of this study were (1) to determine the intra- and interassay precision of the FGF-23 concentrations in dogs as measured via the Kainos ELISA FGF-23 kit, (2) to calculate a reference interval, and (3) to assess the correlation of the FGF-23 concentration with the hematological and biochemical parameters. The coefficient of variation was below 15% for both the intra- and interassay precision, indicating good reproducibility. The reference interval ranged between 95.8 (90% confidence interval: 44.6; 139.2) and 695.1 pg/mL (598.7; 799.1) based on 136 clinically healthy dogs, classified as such according to the information of treating veterinarians as well as the unremarkable results of hematology and biochemistry. The FGF-23 concentration differed significantly between dogs aged <9 and ≥9 years (p = 0.045). Four groups of 10 dogs each were retrospectively formed based on the creatinine concentration classification according to the IRIS staging. Correlation was the strongest for the renal parameters. Statistically significant differences in the FGF-23 concentration were demonstrated between the study groups I and III (p < 0.001), I and IV (p < 0.001), and II and IV (p = 0.005). There was a trend for a rising FGF-23 concentration in older dogs. Due to the wide reference interval, diagnostic cut-offs and/or subject-based FGF-23 reference values in each dog are needed for monitoring and clinical interpretation.

Granulocytic anaplasmosis in cats from central Europe and molecular characterization of feline Anaplasma phagocytophilum strains by ankA gene, groEL gene and multilocus sequence typing

BACKGROUND

Anaplasma phagocytophilum is a Gram-negative obligate intracellular bacterium that replicates in neutrophil granulocytes. It is transmitted by ticks of the Ixodes ricinus complex and causes febrile illness called granulocytic anaplasmosis primarily in humans, horses, dogs, sheep, cattle and goats. In comparison, clinically apparent disease has been described rarely in cats especially compared to dogs and horses. It is currently unknown whether cats are less susceptible to A. phagocytophilum or whether granulocytic anaplasmosis might be underdiagnosed in cats.

METHODS

To address this question, we examined clinical signs and laboratory findings in seven A. phagocytophilum infected cats from Germany and Switzerland. We then genetically characterized feline A. phagocytophilum strains and compared them to those from other hosts showing clinically apparent disease. For this purpose, ankA-based, groEL-based and multilocus sequence typing (MLST) were applied. Furthermore, the concordance between these typing methods was assessed.

RESULTS

Fever, lethargy and anorexia were the most common clinical signs in cats suffering from granulocytic anaplasmosis. The most frequent laboratory finding was thrombocytopenia. All three typing methods consistently indicated that the A. phagocytophilum strains found infecting cats are the same as those that cause disease in humans, dogs and horses. In general, the three typing methods applied exhibited high concordance.

CONCLUSIONS

The genetic characterization of the feline A. phagocytophilum strains indicates that strain divergence is not the explanation for the fact that granulocytic anaplasmosis is much less frequently diagnosed in cats than in dogs and horses. Otherwise, it may be possible that cats are less susceptible to the same strains than dogs and horse are. However, due to the unspecific clinical signs, it should be considered that granulocytic anaplasmosis may be under-diagnosed in cats.

Diagnostic cut-off values for the urinary corticoid:creatinine ratio for the diagnosis of canine Cushing's syndrome using an automated chemiluminescent assay

BACKGROUND

Cushing's syndrome is one of the most common endocrinopathies in dogs. The preferred screening test for spontaneous Cushing's syndrome is the low-dose dexamethasone suppression test (LDDST). The diagnostic value of urinary cortisol:creatinine ratios (UCCR) is questionable.

OBJECTIVES

The aim of this study was to determine diagnostic cut-off values for UCCR testing in comparison with LDDST as a clinical reference standard and to calculate the sensitivity and specificity.

METHODS

Data from 2018 to 2020 were obtained retrospectively from a commercial laboratory. Both LDDST and UCCR were measured by automated chemiluminescent immunoassay (CLIA). The maximum interval between both tests was 14 days. The optimal cut-off value for UCCR testing was calculated by the Youden index. The sensitivity and specificity of these cut-off values for the UCCR test and LDDST were assessed by Bayesian latent class models (BLCMs).

RESULTS

This study included 324 dogs with both UCCR test and LDDST results. The optimal UCCR cut-off value, calculated by the Youden index, was 47.4 × 10-6 . Any UCCR <40 × 10-6 was interpreted as a negative result, 40-60 × 10-6 as values in a gray zone, and >60 × 10-6 as positive. Using the cut-off of 60 × 10-6 , BLCM showed 91% (LDDST) and 86% (UCCR test) sensitivity and a specificity of 54% (LDDST) and 63% (UCCR test).

CONCLUSIONS

Considering an 86% sensitivity and a 63% specificity, UCCR testing may be considered a first-line investigation to rule out Cushing's syndrome using CLIA analysis. Urine samples can be collected noninvasively at home by the owner, reducing the potential impact of stress.

Vector-Borne Pathogens in Stray Cats in Eastern Germany (Thuringia)

Bacterial, protozoal, and viral vector-borne pathogens (VBPs) can cause infections in cats. There is little information on feline VBP prevalence in Germany. Stray cats are frequently exposed to vectors but receive no veterinary care. The aim of this study was to determine the prevalence of selected VBPs in stray cats. EDTA blood and serum samples were taken from apparently healthy stray cats during a spay/neuter campaign in the federal state of Thuringia. Overall, 11/50 (22%) and 32/50 (64%) cats tested positive for at least one VBP by direct and indirect detection methods, respectively. PCR testing of EDTA blood detected hemotropic Mycoplasma spp. in 12% of cats, Hepatozoon spp. in 10%, and Anaplasma phagocytophilum in 4%. PCR testing for Rickettsia spp. and piroplasms was negative. IFAT on serum samples showed 46% of cats had detectable antibodies for Bartonella spp., 30% for Rickettsia spp., and 16% for A. phagocytophilum. The cats were additionally tested for feline coronavirus, FIV, and FeLV to identify potential risk factors for pathogen contact and/or infections. No correlation between FIV and FeLV status and VBP positivity was detected. Anaplasma phagocytophilum, Rickettsia spp., and Bartonella spp. have zoonotic potential, and surveillance is recommended in the context of the One Health approach.

The Indirect Antiglobulin (Coombs') Test Is Specific but Less Sensitive Than the Direct Antiglobulin Test for Detecting Anti-Erythrocytic Autoantibodies and Thereby Immune-Mediated Hemolytic Anemia in Dogs

The immunodiagnostic assessment of dogs suspected of having immune-mediated hemolytic anemia (IMHA) is based on persistent autoagglutination of erythrocytes (after three saline washes), marked spherocytosis, and a positive direct antiglobulin (Coombs') test (DAT). However, the value of using the indirect antiglobulin test (IAT) for the detection of anti-erythrocytic autoantibodies in serum from dogs suspected of having IMHA is unclear. To evaluate the IAT, leftover serum samples from a large cohort of 94 dogs suspected of having IMHA and for which DAT results were known were incubated with DAT- erythrocytes, and five IAT techniques were performed (in part with different reagents and temperatures): microtiter plate (MICRO), microcapillary, laboratory gel column, gel minitube kit (GEL KIT), and immunochromatographic strip kit. Two IAT techniques (MICRO at 37 °C and GEL KIT with rabbit anti-dog polyvalent reagent) detected autoantibodies against erythrocytes in serum from 53% and 57% of DAT+ dogs, respectively, while other IATs performed less well. Moreover, while the analytic specificity of the IAT methods compared to the DAT ranged from 96-100%, the sensitivity range was only 9-57%. Thus, we still recommend DAT for diagnosis and monitoring of IMHA in dogs but conclude that a positive IAT result may aid diagnostically when serum is available, but fresh red blood cells are not.

Comparison of Three Different Diagnostic Assays for Fibroblast Growth Factor-23 (FGF-23) Measurements in Cats: A Pilot Study

Fibroblast growth factor-23 (FGF-23) is a phosphaturic hormone used to monitor chronic kidney disease (CKD) in humans. The aim of this pilot study was to compare three diagnostic assays and to assess how the results correlate with parameters of renal dysfunction in cats. Four groups of 10 cats each were formed retrospectively according to creatinine, based on IRIS staging. FGF-23 was measured using two different ELISAs (MyBioSource and Kainos ELISA FGF-23 Kit) and an automated assay on the DiaSorin Liaison platform. Measurements were performed in 40 cats. Spearman's rank correlation coefficient showed a strong correlation between the Kainos and DiaSorin assays (ρ = 0.742/p < 0.001) and a low correlation (ρ = 0.443/p = 0.005) between the Kainos and MyBioSource assays. The measurements with the Kainos assay strongly correlated with urea (ρ = 0.835/p < 0.001) and creatinine (ρ = 0.764/p < 0.001), and moderately correlated with SDMA (ρ = 0.580/p < 0.001) and phosphorus (ρ = 0.532/p < 0.001). The results of the MyBioSource and DiaSorin assays only showed a moderate correlation with urea (ρ = 0.624/0.572) and creatinine (ρ = 0.622/0.510) concentrations (p = 0.001 each). The Kainos assay showed the strongest correlation (ρ = 0.806) with the various creatinine concentrations according to the IRIS, followed by the MyBioSource (ρ = 0.663/p < 0.001) and DiaSorin assays (ρ = 0.580/p < 0.001). Overall, the Kainos assay demonstrated the best correlations with both biomarkers and various creatinine concentrations according to the IRIS. Individual assay-based reference values should be established to make a reliable interpretation of FGF-23 levels possible to diagnose or monitor feline CKD.

Pilot testing the EARS-Vet surveillance network for antibiotic resistance in bacterial pathogens from animals in the EU/EEA

Introduction

As part of the EU Joint Action on Antimicrobial Resistance (AMR) and Healthcare-Associated Infections, an initiative has been launched to build the European AMR Surveillance network in veterinary medicine (EARS-Vet). So far, activities included mapping national systems for AMR surveillance in animal bacterial pathogens, and defining the EARS-Vet objectives, scope, and standards. Drawing on these milestones, this study aimed to pilot test EARS-Vet surveillance, namely to (i) assess available data, (ii) perform cross-country analyses, and (iii) identify potential challenges and develop recommendations to improve future data collection and analysis.

Methods

Eleven partners from nine EU/EEA countries participated and shared available data for the period 2016-2020, representing a total of 140,110 bacterial isolates and 1,302,389 entries (isolate-antibiotic agent combinations).

Results

Collected data were highly diverse and fragmented. Using a standardized approach and interpretation with epidemiological cut-offs, we were able to jointly analyze AMR trends of 53 combinations of animal host-bacteria-antibiotic categories of interest to EARS-Vet. This work demonstrated substantial variations of resistance levels, both among and within countries (e.g., between animal host species).

Discussion

Key issues at this stage include the lack of harmonization of antimicrobial susceptibility testing methods used in European surveillance systems and veterinary diagnostic laboratories, the absence of interpretation criteria for many bacteria-antibiotic combinations of interest, and the lack of data from a lot of EU/EEA countries where little or even surveillance currently exists. Still, this pilot study provides a proof-of-concept of what EARS-Vet can achieve. Results form an important basis to shape future systematic data collection and analysis.

Feline leishmaniosis with focus on ocular manifestation: a case report

BACKGROUND

In Europe, feline leishmaniosis is commonly caused by Leishmania infantum. There is little knowledge regarding pathogenesis, ocular manifestations and long-term follow-ups in cats with leishmaniosis.

FINDINGS

A 6-year-old female, spayed European Shorthair cat was imported from Spain to Germany 2 years prior to its first clinical presentation. The cat showed lethargy, weight loss, ulcerative lesions on the front limbs and high-grade chronic uveitis. The diagnosis of L. infantum infection was based on the cytological finding of amastigotes in skin lesions, positive qPCR of EDTA-blood and positive PCR of a cyto-brush sample from the conjunctiva. Supportive findings included positive serology by IFAT, serum protein capillary electrophoresis with peaks in alpha2- and gamma-globulin sections and marked elevation of SAA. Enucleation had to be performed on day 288 on both eyes because of blindness, glaucoma and high-grade uveitis. Histologically, high numbers of Leishmania spp. amastigotes were found in histiocytes. IFAT and PCR were positive in the aqueous humor in both eyes, respectively. Feline leukemia virus antigen and feline immunodeficiency virus antibody testings were positive. Hematological and biochemical results revealed mild leukocytosis with lymphocytosis, monocytosis and eosinopenia as well as marked elevation of SAA and hyperglobulinemia. The cat was treated with allopurinol, responded well and was still alive at follow-up on day 288 after first presentation. However, enucleation was necessary because of refractory glaucoma and uveitis.  CONCLUSION: For the first time, ocular evidence of Leishmania IgG antibodies was demonstrated in the aqueous humor of both eyes in cats. There is limited knowledge about the pathogenesis, treatment options and outcomes in cats infected with L. infantum. This case report supports the hypothesis that immunosuppression increases the risk of clinical signs of leishmaniasis in cats. Alpha2- and gamma-globulin peaks in serum protein capillary electrophoresis are supportive criteria for the diagnosis of L. infantum infection. SAA is valuable for monitoring. Regarding ophthalmology, uveitis and glaucoma may have a poor prognosis.

Robust and Easy-to-Use One-Pot Workflow for Label-Free Single-Cell Proteomics

The analysis of ultralow input samples or even individual cells is essential to answering a multitude of biomedical questions, but current proteomic workflows are limited in their sensitivity and reproducibility. Here, we report a comprehensive workflow that includes improved strategies for all steps, from cell lysis to data analysis. Thanks to convenient-to-handle 1 μL sample volume and standardized 384-well plates, the workflow is easy for even novice users to implement. At the same time, it can be performed semi-automatized using CellenONE, which allows for the highest reproducibility. To achieve high throughput, ultrashort gradient lengths down to 5 min were tested using advanced μ-pillar columns. Data-dependent acquisition (DDA), wide-window acquisition (WWA), data-independent acquisition (DIA), and commonly used advanced data analysis algorithms were benchmarked. Using DDA, 1790 proteins covering a dynamic range of four orders of magnitude were identified in a single cell. Using DIA, proteome coverage increased to more than 2200 proteins identified from single-cell level input in a 20 min active gradient. The workflow enabled differentiation of two cell lines, demonstrating its suitability to cellular heterogeneity determination.

Thyroid hormones in canine pregnancy and lactation

It is believed that thyroid function has a significant effect on fertility and fetal development in mammals. So far, however, only few studies have been published about potential effects of the reproductive cycle stage on thyroid hormone concentrations in dogs. Therefore, over the course of 122 pregnant and non-pregnant cycles in healthy bitches, Thyroid stimulating hormone (TSH), free Thyroxine (fT4), total Thyroxine (tT4) and Progesterone (P4) were measured six times to assess the influence of the cycle stage and pregnancy on hormone concentrations. The aim was to evaluate established reference intervals for the thyroid hormones in a female study population. Of the 122 bitches, 98 became pregnant. Blood samples were collected during estrus, three times in pregnancy, during lactation and after weaning, or at equivalent times during and after estrus in non-pregnant dogs. No differences between pregnant and non-pregnant animals in any of the thyroid hormones were found. Hormone concentrations, however, differed significantly between the six samplings (p < .01). TSH initially declined during pregnancy, then rose again. The mean concentration of all dogs exceeded the overall upper reference limit of 0.70 ng/mL during lactation. Concentrations of tT4 and ft4 increased during the first third of pregnancy and then subsequently declined. The overall reference limits for tT4 were 0.47-3.20 μg/dL, and for fT4 4.86-29.60 pmol/L, but the reference intervals varied between the sampling dates. The observed patterns may reflect that maternal tT4 and fT4 seem to have important effects during early pregnancy, including a pronounced negative feedback effect on TSH. The initial increase and subsequent decline of tT4 and fT4 concentrations during the course of pregnancy is in accordance with findings in humans and may support the development of fetal thyroid function. The observed peak of TSH concentrations during lactation suggests that the demand for thyroid hormones in this phase is largest. Even if the underlying causes and mechanisms of thyroid regulation are not fully understood, the results of this study show relevant changes of hormone concentrations in the course of the sexual cycle and pregnancy. In that regard, cycle stage needs to be considered when assessing thyroid function in bitches.

Molecular and Serological Detection of Anaplasma phagocytophilum in Dogs from Germany (2008-2020)

Anaplasma phagocytophilum is an obligate intracellular bacterium that causes granulocytic anaplasmosis in domestic animals, wildlife, and humans and is primarily transmitted by ticks of the Ixodes persulcatus complex. This retrospective study aims to determine the percentages of dogs that tested positive for A. phagocytophilum in Germany. It included the results of direct (polymerase chain reaction [PCR]) and indirect (immunofluorescence antibody test [IFAT], antibody-enzyme-linked immunosorbent assay [ELISA]) detection methods performed in the laboratory LABOKLIN on canine samples provided by German veterinarians from 2008 to 2020. Out of a total of 27,368 dogs tested by PCR, 1332 (4.9%) tested positive, while 24,720 (27.4%) of the 90,376 dogs tested by IFAT/ELISA had positive serology. High rates of positive PCR results were observed in months with known peaks in vector activity, showing that the dynamics of A. phagocytophilum infections in dogs in Germany are consistent with vector activity. In dogs with a positive PCR result, peaks in serology could be observed four weeks after initial testing. Male and senior dogs had higher rates of positive serology. A possible impact of environmental factors such as changes in climate should be investigated further. Overall, the upward trend in positive test results over the years indicates that canine granulocytic anaplasmosis will continue to become increasingly important for veterinary medicine.

Integration of Li4Ti5O12 Crystalline Films on Silicon Toward High-Rate Performance Lithionic Devices

The growth of crystalline Li-based oxide thin films on silicon substrates is essential for the integration of next-generation solid-state lithionic and electronic devices including on-chip microbatteries, memristors, and sensors. However, growing crystalline oxides directly on silicon typically requires high temperatures and oxygen partial pressures, which leads to the formation of undesired chemical species at the interface compromising the crystal quality of the films. In this work, we employ a 2 nm gamma-alumina (γ-Al₂O₃) buffer layer on Si substrates in order to grow crystalline thin films of Li₄Ti₅O₁₂ (LTO), a well-known active material for lithium-ion batteries. The ultrathin γ-Al₂O₃ layer enables the formation of a stable heterostructure with sharp interfaces and drastically improves the LTO crystallographic and electrochemical properties. Long-term galvanostatic cycling of 50 nm LTO films in liquid-based half-cells demonstrates a high capacity retention of 91% after 5000 cycles at 100 C. Rate capability tests showcase a specific charge of 56 mA h g^-1 at an exceptional C-rate of 5000 C (15 mA cm^-2). Moreover, with sub-millisecond current pulse tests, the reported thin-film heterostructure exhibits rapid Li-ion (de)intercalation, which could lead to fast switching timescales in resistive memory devices and electrochemical transistors.

Autochthonous Babesia canis infections in 49 dogs in Germany

BACKGROUND

Vector-borne diseases are of increasing importance in Germany. Since 2015, autochthonous cases have been increasingly documented in Berlin/Brandenburg.

OBJECTIVES

Describe autochthonous Babesia canis infection in the Berlin/Brandenburg region.

ANIMALS

Forty-nine dogs with autochthonous B. canis infection.

METHODS

Evaluation of history, clinical signs, laboratory abnormalities, treatment, and outcome.

RESULTS

Dogs were presented between March and August (9) and September and January (40) in the years 2015-2021. Historical and clinical findings were lethargy (100%), pale mucous membranes (63%), fever (50%), and pigmenturia (52%). Common clinicopathological findings were thrombocytopenia (100%), anemia (85%), intravascular hemolysis (52%), pancytopenia (41%), and systemic inflammatory response syndrome (SIRS; 37%). Babesia detection was based on blood smear evaluation (n = 40) and PCR targeting the 18S rRNA gene of piroplasms (n = 49). Sequencing indicated 99.47% to 100% identity to B. canis sequences from GenBank. All dogs were treated with imidocarb (2.4-6.3 mg/kg; median, 5 mg/kg); 8 dogs received 1, 35 received 2, and 1 dog each received 3, 4, or 5 injections, respectively. Continued PCR-positive results were detected in 7 dogs after the 1st, in 5 after the 2nd, in 2 after the 3rd, and in 1 28 days after the 4th injection. Four dogs were euthanized and 3 dogs died.

CONCLUSIONS AND CLINICAL IMPORTANCE

Autochthonous B. canis infections in Berlin/Brandenburg were associated with severe clinicopathological changes, SIRS, and multiorgan involvement. Testing by PCR during and after treatment is advisable to monitor treatment success. Screening of blood donors in high-risk areas and year-round tick protection is strongly recommended.

Metabolomics during canine pregnancy and lactation

During pregnancy and parturition, female dogs have to cope with various challenges such as providing nutrients for the growth of the fetuses, hormonal changes, whelping, nursing, milk production, and uterine involution. Metabolomic research has been used to characterize the influence of several factors on metabolism such as inter- and intra-individual factors, feeding, aging, inter-breed differences, drug action, behavior, exercise, genetic factors, neuter status, and pathologic processes. Aim of this study was to identify metabolites showing specific changes in blood serum at the different phases of pregnancy and lactation. In total, 27 privately owned female dogs of 21 different breeds were sampled at six time points: during heat, in early, mid and late pregnancy, at the suspected peak of lactation and after weaning. A validated and highly automated canine-specific NMR metabolomics technology was utilized to quantitate 123 measurands. It was evaluated which metabolite concentrations showed significant changes between the different time points. Metabolites were then grouped into five clusters based on concentration patterns and biochemical relationships between the metabolites: high in mid-pregnancy, low in mid-pregnancy, high in late pregnancy, high in lactation, and low in lactation. Several metabolites such as albumin, glycoprotein acetyls, fatty acids, lipoproteins, glucose, and some amino acids show similar patterns during pregnancy and lactation as shown in humans. The patterns of some other parameters such as branched-chain amino acids, alanine and histidine seem to differ between these species. For most metabolites, it is yet unstudied whether the observed changes arise from modified resorption from the intestines, modified production, or metabolism in the maternal or fetal tissues. Hence, further species-specific metabolomic research may support a broader understanding of the physiological changes caused by pregnancy that are likely to be key for the normal fetal growth and development. Our findings provide a baseline of normal metabolic changes during healthy canine pregnancy and parturition. Combined with future metabolomics findings, they may help monitor vital functions of pre-, intra-, and post-partum bitches and may allow early detection of illness.

Ein Update zur Leishmaniose des Hundes: Diagnostik, Therapie und Monitoring

Aufgrund von steigenden Importzahlen von Hunden aus dem Ausland, zunehmendem Reiseverkehr sowie den Veränderungen klimatischer Bedingungen in Europa gewinnen Infektionen mit Leishmania (L.) infantum bei Hunden in Deutschland zunehmend an Bedeutung. Daher sollten auch Hunde aus dem Ausland, die keine klinischen Symptome zeigen, direkt nach Import sowie erneut 6 Monate später auf vektorübertragene Infektionserreger getestet werden. Bei Hunden mit klinischer Symptomatik, die hinweisend auf eine Leishmaniose sind, werden direkte und indirekte Nachweisverfahren sowie eine hämatologische und biochemische Untersuchung unter Einbezug von Serumeiweißelektrophorese sowie Bestimmung des C-reaktiven Proteins empfohlen. Als Leitfaden für die Therapie sowie das Monitoring stehen die LeishVet-Guidelines zur Verfügung. Es stehen leishmanizide und leishmaniostatische Wirkstoffe zur Verfügung, die in first-line, second-line und third-line unterschieden werden. Zur Anpassung der Allopurinol-Dosierung wird der Stufenplan empfohlen. Aufgrund der Veränderung der klimatischen Bedingungen kommt es zu einer Ausbreitung der Habitate von Sandmücken, die als Vektoren der Leishmaniose bekannt sind. Als weitere Infektionsquellen sind Deckakte, transplazentare Infektionen, Bisswunden und Bluttransfusionen beschrieben. Leishmania infantum hat zoonotisches Potential und ist daher auch in Hinblick auf den „One-Health“-Gedanken bedeutend.

A modern look at a medieval bilayer metal leaf: nanotomography of Zwischgold

Many European sculptures and altarpieces from the Middle Ages were decorated with Zwischgold, a bilayer metal leaf with an ultra-thin gold face backed by silver. Zwischgold corrodes quickly when exposed to air, causing the surface of the artefact to darken and lose gloss. The conservation of such Zwischgold applied artefacts has been an obstinate problem. We have acquired quantitative, 3D nanoscale images of Zwischgold samples from 15^th century artefacts and modern materials using ptychographic X-ray computed tomography (PXCT), a recently developed coherent diffractive imaging technique, to investigate the leaf structure and chemical state of Zwischgold. The measurements clearly demonstrate decreasing density (increasing porosity) of the leaf materials and their corrosion products, as well as delamination of the leaves from their substrate. Each of these effects speak to typically observed issues in the conservation of such Zwischgold applied artefacts. Further, a rare variant of Zwischgold that contains extremely thin multiple gold layers and an overlapping phenomenon of Zwischgold with other metal leaves are observed through PXCT. As supportive data, scanning electron microscopy (SEM) and scanning transmission electron microscopy (STEM) coupled with energy dispersive X-ray analysis (EDX) were performed on the medieval samples.

First evidence of vertical Hepatozoon canis transmission in dogs in Europe

Background

Hepatozoon canis is a protozoal agent that is known to be transmitted by oral uptake of H. canis-infected Rhipicephalus sanguineus sensu lato ticks in dogs. Vertical transmission of H. canis has only been described once in a study evaluating dogs from Japan. The aim of this study was to investigate the parasitological status of puppies from a bitch that had tested positive for Hepatozoon spp. prior to giving birth.

Findings

A 4-year-old, female, pregnant dog imported from Italy (Sardinia) to Germany showed clinical signs of lethargy and tachypnoea and tested positive for H. canis by PCR. The dog gave birth to eight puppies, one of which was stillborn and another that had to be reanimated. Haematology, buffy coat analysis and a biochemistry profile were performed for each dog. EDTA-blood of the surviving seven puppies and bone marrow, liver, spleen, amniotic fluid, and umbilical cord of the stillborn puppy was tested for the presence of Hepatozoon spp. by PCR.

The mother and the seven surviving puppies tested positive for H. canis by PCR at day 62 post-partum. Gamonts were detected in all dogs by buffy coat evaluation. Haematological and biochemistry results revealed mild abnormalities. In the stillborn puppy, spleen, umbilical cord, and amniotic fluid were positive for H. canis.

Conclusion

The results confirm that vertical transmission is a possible route of H. canis infection in dogs, demonstrated by molecular detection of the pathogen in the stillborn puppy. In the seven surviving puppies, vertical transmission was the most likely transmission route. A potential impact of the level of parasitaemia on the health of puppies, as well as its pathogenesis, should be investigated further.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-022-05392-7.

Metabolic changes associated with two endocrine abnormalities in dogs: elevated fructosamine and low thyroxine

INTRODUCTION

Metabolomics studies in canine endocrine abnormalities are sparse and basic information on these abnormalities must be generated.

OBJECTIVES

To characterize the metabolic changes associated with elevated fructosamine, reflecting poor glycemic control, and low thyroxine, a thyroid hormone controlling metabolism.

METHODS

Leftovers of clinical serum samples; 25 controls, 79 high fructosamine, and 47 low thyroxine, were analyzed using ¹H NMR and differences were evaluated using Firth logistic regression.

RESULTS

Both high fructosamine and low thyroxine were associated with changes in concentrations of multiple metabolites, including glycoprotein acetyls and lipids.

CONCLUSION

These findings suggest promising makers for further research and clinical validation.

High genetic diversity of Babesia canis (Piana & Galli-Valerio, 1895) in a recent local outbreak in Berlin/ Brandenburg, Germany

Canine babesiosis caused by Babesia canis (Piana & Galli-Valerio, 1895) is emerging in new regions in Europe since its vector Dermacentor reticulatus (Fabricius, 1794) is expanding its geographic range. In the Berlin/Brandenburg area in northeast Germany, D. reticulatus is highly abundant but in the past only one autochthonous B. canis infection was reported. Since 2015, autochthonous cases were occasionally diagnosed but numbers increased since autumn 2019. The aim of the study was to genotype autochthonous canine Babesia spp. infections from Berlin/Brandenburg. Between 04/2015 and 01/2022, 46 dogs with acute babesiosis were presented to the small animal clinic (one dog was infected twice resulting in 47 samples). There were 32 dogs that had never left Berlin/Brandenburg and 14 others that had not left the region in the 6 weeks prior to disease onset. PCRs targeting the 18S rRNA and the Bc28.1 merozoite surface antigen were positive in 47 and 42 samples, respectively. Sequencing of cloned PCR products identified all samples as B. canis with 17 18S rRNA and 12 Bc28.1 haplotypes. Based on network analysis for 18S rRNA sequences and a previously described polymorphic dinucleotide, samples were assigned to two distinct clusters. One contained 31 and the other 16 samples. Using network analysis, the Bc28.1 haplotypes could also be separated into two clusters differing by at least five polymorphisms. Analyses of sequences from multiple clones indicated the presence of up to five 18S rRNA and eight Bc28.1 haplotypes and thus high parasite variability in an individual host. The genetic diversity could suggest that the parasites in the region have multiple origins, but diversity in individual dogs and dog populations from endemic regions is unknown. The suitability of both markers for genotyping is questionable due to potential intragenomic diversity for the rRNA and high intergenomic variability for the Bc28.1 marker.

A Common Missense Variant Causing Factor XI Deficiency and Increased Bleeding Tendency in Maine Coon Cats

Hereditary factor XI (FXI) deficiency is characterized as an autosomal mild to moderate coagulopathy in humans and domestic animals. Coagulation testing revealed FXI deficiency in a core family of Maine Coon cats (MCCs) in the United States. Factor XI-deficient MCCs were homozygous for a guanine to adenine transition resulting in a methionine substitution for the highly conserved valine-516 in the FXI catalytic domain. Immunoblots detected FXI of normal size and quantity in plasmas of MCCs homozygous for V516M. Some FXI-deficient MCCs experienced excessive post-operative/traumatic bleeding. Screening of 263 MCCs in Europe revealed a mutant allele frequency of 0.232 (23.2%). However, V516M was not found among 100 cats of other breeds. Recombinant feline FXI-M516 (fFXI-M516) expressed ~4% of the activity of wild-type fFXI-V516 in plasma clotting assays. Furthermore, fFXIa-M516 cleaved the chromogenic substrate S-2366 with ~4.3-fold lower catalytic efficacy (kcat/Km) than fFXIa-V516, supporting a conformational alteration of the protease active site. The rate of FIX activation by fFXIa-M516 was reduced >3-fold compared with fFXIa-V516. The common missense variant FXI-V516M causes a cross-reactive material positive FXI deficiency in MCCs that is associated with mild-moderate bleeding tendencies. Given the prevalence of the variant in MCCs, genotyping is recommended prior to invasive procedures or breeding.

[Feline uroliths: Analysis of frequency and epidemiology in Germany (2016-2020)]

OBJECTIVES

This study was aimed to assess the distribution and frequency of uroliths in cats as well as to evaluate gender-, age-, and breed-specific differences.

MATERIAL AND METHODS

3629 uroliths from cats in Germany were analyzed by infrared-spectroscopy during the period 2016-2020. The majority (3300) of the uroliths originated from purebred cats of 22 breeds.

RESULTS

Uroliths were prevalent in the order of male neutered (45.3 %), female spayed (35.3 %), male intact (7.4 %), and female intact cats (6.3 %). Median age of the cats with uroliths was 7 years, although it varied slightly depending on types of the urolith. The most frequent uroliths were calcium oxalate (59.5 %), followed by struvite (33.7 %), ammonium urate (2 %), calcium phosphate (1.7 %), cystine (0.7 %) and xanthine (0.4 %). Males (59.4 %) and females (59.2 %) showed nearly identical prevalence of calcium oxalates, whereas it significantly diverged in castrated (60.2 %) versus intact animals (54.4 %; p = 0.01). With regard to struvites, male cats (32.6 %) were less prone than females (35.4 %; p = 0.08) while intact cats (38.2 %) significantly outnumbered the castrated cohorts (33.1 %; p = 0.02). The prevalence for calcium oxalate uroliths increased by 6.6 % during the study period, contrasting a decrease of 5.5 % for struvites. Some breeds (> 10 individuals) showed significantly higher propensities than others for urolith formation. Calcium oxalates were significantly more frequent in British shorthair cats (85.2 %), Ragdoll (75 %), Scottish fold (74.1 %) and Persians (72.4 %). Struvites were prevailing in Norwegian forest cats (48.5 %), British longhair (41.7 %), European shorthair (41.7 %) and Siberian forest cats (36.8 %). Siamese cats had the significantly highest percentage of cystine uroliths (16 %).

CONCLUSIONS AND CLINICAL RELEVANCE

The occurrence of urine calculi in cats from Germany was found to be most frequent for calcium oxalate and struvite types. We also found breed-, age-, gender- specific differences in addition to variations depending on the neutering status of the animals.

Metabolomic serum abnormalities in dogs with hepatopathies

Hepatopathies can cause major metabolic abnormalities in humans and animals. This study examined differences in serum metabolomic parameters and patterns in left-over serum samples from dogs with either congenital portosystemic shunts (cPSS, n = 24) or high serum liver enzyme activities (HLEA, n = 25) compared to control dogs (n = 64). A validated targeted proton nuclear magnetic resonance spectroscopy platform was used to assess 123 parameters. Principal component analysis of the serum metabolome demonstrated distinct clustering among individuals in each group, with the cluster of HLEA being broader compared to the other groups, presumably due to the wider spectrum of hepatic diseases represented in these samples. While younger and older adult control dogs had very similar metabolomic patterns and clusters, there were changes in many metabolites in the hepatopathy groups. Higher phenylalanine and tyrosine concentrations, lower branched-chained amino acids (BCAAs) concentrations, and altered fatty acid parameters were seen in cPSS dogs compared to controls. In contrast, dogs with HLEA had increased concentrations of BCAAs, phenylalanine, and various lipoproteins. Machine learning based solely on the metabolomics data showed excellent group classification, potentially identifying a novel tool to differentiate hepatopathies. The observed changes in metabolic parameters could provide invaluable insight into the pathophysiology, diagnosis, and prognosis of hepatopathies.

Prevalence of anti-severe acute respiratory syndrome coronavirus 2 antibodies in cats in Germany and other European countries in the early phase of the coronavirus disease-19 pandemic

During the first months of the coronavirus disease (COVID‐19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), cases of human‐to‐cat transmission were reported. Seroconversion was shown in cats infected under experimental and natural conditions. This large‐scale survey of 1,005 serum samples was conducted to investigate anti‐SARS‐CoV‐2 antibody prevalence in domestic cats during the first 7 months of the pandemic in Germany and other European countries. In addition, we compared the sensitivity and specificity of two multispecies SARS‐CoV‐2 antibody enzyme‐linked immunosorbent assays (ELISA). Results were confirmed by using an indirect immunofluorescence test (iIFT) and a surrogate virus neutralization test (sVNT). Sera that were highly positive for feline coronavirus (FCoV) antibodies (n = 103) were included to correct for cross‐reactivity of the tests used. Our results showed an overall SARS‐CoV‐2 seropositivity of 1.9% (n = 19) in a receptor‐binding domain (RBD)‐based ELISA, additional 0.8% (n = 8) were giving inconclusive results. In contrast, a nucleocapsid‐based ELISA revealed 0.5% (n = 5) positive and 0.2% (n = 2) inconclusive results. While the iIFT and sVNT confirmed 100% of positive and 50%–57.1% of the doubtful results as determined in the RBD ELISA, the nucleocapsid‐based assay showed a high discrepancy and only one of the five positive results could be confirmed. The results indicate significant deficits of the nucleocapsid‐based ELISA with respect to sensitivity and specificity. Due to a significantly higher rate (5.8%) of positive results in the group of highly FCoV antibody‐positive samples, cross‐reactivity of the FCoV‐ELISA with SARS‐CoV‐2 antibodies cannot be excluded. Furthermore, we investigated the impact of direct contact of domestic cats (n = 23) to SARS‐CoV‐2 positive owners. Considering one inconclusive result, which got confirmed by iIFT, this exposure did not lead to a significantly higher prevalence (4.4%; p = .358) among tested subjects. Overall, we conclude that cats are a negligible entity with respect to virus transmission in Europe.

Screening of Antimicrobial Activity of Essential Oils against Bovine Respiratory Pathogens - Focusing on Pasteurella multocida

Administration of essential oils as natural plant products with antimicrobial activity might be an alternative to antibiotic treatment of bovine respiratory disease. The aim of this study was to analyse the in vitro antimicrobial activity of 11 essential oils against Pasteurella multocida isolated from the respiratory tract of calves using microdilution with determination of minimum inhibitory and bactericidal concentration as well as agar disc diffusion. Additionally, antimicrobial activity against Mannheimia haemolytica and bacteria in the Mannheimia clade was assessed by agar disc diffusion. Seven essential oil mixtures were also tested against all bacterial isolates. P. multocida was strongly inhibited by cinnamon cassia and lemongrass oil followed by coriander, winter savory, thyme, clove, and peppermint oil in the microdilution assays. Eucalyptus, wintergreen, spruce, and star anise oil showed lower activity. Comparison of both methods revealed an underestimation of cinnamon cassia oil activity by agar disc diffusion and conflicting results for wintergreen oil in microdilution, which precipitated in broth. Cinnamon cassia, thyme, wintergreen, lemongrass, and winter savory oil all showed strong antimicrobial activity against M. haemolytica. Bacteria in the Mannheimia clade were mostly inhibited by cinnamon cassia and thyme oil. Pasteurella isolates were more susceptible to inhibition by essential oils than Mannheimia isolates. Essential oil mixtures did not show stronger antibacterial activity than single essential oils. In conclusion, cinnamon cassia and lemongrass as well as coriander, winter savory, and thyme oil are promising candidates for treatment of P. multocida-associated bovine respiratory infections.

[Effects of oral manganese supplementation with different compounds on the manganese whole blood and serum concentrations of broodmares and their suckling foals]

OBJECTIVE

This study aimed to examine the effects of an oral supplementation on manganese (Mn) concentrations in the blood of lactating warm-blood broodmares. Furthermore, the potential relationship between Mn supply of the lactating mare and its suckling foal was investigated.

MATERIAL AND METHODS

During the 90-day trial, lactating mares were divided into 3 groups and daily received a daily dose of either a placebo (n = 11) or a Mn supplement of 560 mg Mn as Mn sulfate (n = 11) or Mn chelate (n = 11) in addition to the Mn intake from the basal ration (hay ad libitum, total mixed ration: Mn intake ~ 100 mg/kg dry matter). Blood samples were taken from the mares and their foals in 14-day intervals. The Mn determination in serum and whole blood as well as in the mare's milk was carried out by means of mass spectrometry with inductively coupled plasma. The Mn analysis in representative feed samples was performed by means of atomic absorption spectrometry. Data were assessed using the software IBM SPSS Statistics 27 (IBM Deutschland GmbH, Ehningen).

RESULTS

During the trial period, the mares showed Mn concentrations 10-fold higher in whole blood (median: 15.6 µg/l; 25-75 percentile: 12.8-18.5 µg/l) than in serum (median: 1.54 µg/l; 25-75 percentile: 1.20-1.90 µg/l). The foals had Mn whole-blood concentrations 16.4-fold higher (median: 21.3 µg/l; 25-75 percentile: 16.7-28.1 µg/l) compared to their serum (median: 1.50 µg/l; 25-75 percentile: 1.30-1.70 µg/l). The Mn whole-blood levels of the foals corresponded to 1.6-fold the Mn concentration of their dams. The milk contained a median Mn concentration of 0.012 mg/kg fresh matter. Mn supplementation had no effect on the Mn blood levels of mares and their foals.

CONCLUSION AND CLINICAL RELEVANCE

Blood Mn concentrations were not affected by the Mn supplementation. However, the Mn levels differed significantly between serum and whole blood. In addition, the Mn concentrations in whole blood of suckling foals were higher compared to their dams, although the Mn concentrations in the mare's milk were low regardless of Mn supplementation. Due to the low Mn content in milk, early Mn supply, preferably by forages, is necessary to ensure that the foals are supplied with Mn according to their requirement.

Molecular detection of Hepatozoon species infections in domestic cats living in Germany

OBJECTIVES

Three species of protozoal Hepatozoon species (H felis, H canis and H silvestris) are known to infect cats in Europe. The objective of this study was to determine the prevalence of Hepatozoon species in samples from cats living in Germany that were submitted to a veterinary laboratory.

METHODS

The study included cats tested for Hepatozoon species by PCR between 2007 and 2020 by the Laboklin laboratory. Travel history and haematological results were documented for cats with positive test results. From 2018 onwards, a partial 18S rRNA Hepatozoon gene fragment was sequenced from cats with positive PCR results.

RESULTS

Sixty-four of 931 cats (7%) tested positive for Hepatozoon species. Sex and age did not have a statistically significant impact. Sequencing was carried out for 16 samples and revealed H felis in all cases. All cats with positive test results and a relevant travel history had been imported from the Mediterranean or south-eastern Europe. There were no autochthonous infections with Hepatozoon species. Leukocytosis, haemoconcentration and anaemia were the most common haematological abnormalities.

CONCLUSIONS AND RELEVANCE

Although infections with Hepatozoon species in cats are usually subclinical, it may be useful to screen cats imported from the Mediterranean and south-eastern Europe for these pathogens to prevent local transmission cycles. There was no evidence of autochthonous infections in Germany; however, further investigations regarding a possible transmission of Hepatozoon species from infected cats to blood-feeding arthropods in Germany may be of interest. To avoid potential spread of the pathogens, ectoparasite prophylaxis is advisable.

Herpesviruses in Captive Chelonians in Europe Between 2016 and 2020

Herpesviruses are important pathogens in tortoises and turtles, yet little is known about the epidemiology of these viruses. We analyzed herpesviruses detected by PCR in samples from captive chelonians in Europe according to virus strain, host species, year and season in which the animal was tested, and country in which the animal was kept. A total of 4,797 samples submitted to a diagnostic laboratory in Europe between January 2016 and December 2020 were evaluated. Of these, 312 (6.50%) were positive for herpesviruses. The types most commonly found were testudinid herpesvirus (TeHV)1 (143 positive, 45.83%) and TeHV3 (153 positive, 49.04%), but also included TeHV2 (1 positive, 0.32%), TeHV4 (3 positive, 0.96%), Terrapene herpesvirus 1 (7 positive, 2.24%), Trachemys herpesvirus 1 (2 positive, 0.64%), and three previously undescribed herpesviruses (0.96%). Herpesviruses were detected in chelonians in the families Testudinidae, Emydidae, Geoemydidae, and in the suborder Pleurodira. Among the species for which 100 samples or more were available, the highest proportions of positive samples (positivity rates) were found in samples from Horsfield's tortoises (Testudo horsfieldii) (14.96%), and radiated tortoises (Astrochelys radiata) (14.05%). Among tortoises (Testudinidae), viruses were most often detected in the spring, while in emydid turtles (Emydidae) they were most often detected in the summer. A comparison of the positivity rates according to country showed significant differences, with the highest rate in samples from Italy (16.01%). This study indicated possible differences in herpesvirus positivity rates depending on host species, virus strain, year of sampling, season, and country of origin. It provides useful information in further understanding fluctuations in infection rates as well as in helping to guide decision making for herpesvirus diagnostics in chelonian patients. It also provides evidence for the international dispersal of herpesviruses with their hosts through international trade.

A testudinid herpesvirus 1 (TeHV1)-associated disease outbreak in a group of Horsfield's tortoises (Testudo horsfieldii)

In spring 2020, a severe disease outbreak with high morbidity and mortality was observed in a collection of 15 Horsfield's tortoises (Testudo horsfieldii). Affected tortoises showed upper respiratory- and gastrointestinal tract signs, including rhinitis and stomatitis. Testudinid herpesvirus 1 (TeHV1) and Mycoplasma spp. were detected by PCR in oral swabs of affected animals. Histological examination of one deceased animal showed intranuclear inclusion bodies typical for herpesvirus infections in liver, spleen and oesophagus. The virus was likely introduced into the collection 2 years earlier by a clinically healthy Horsfield's tortoise that was tested positive for TeHV1 by PCR.

SARS-CoV-2-Specific Antibodies in Domestic Cats during First COVID-19 Wave, Europe

We conducted a severe acute respiratory syndrome coronavirus 2 antibody seroprevalence study among >2,000 domestic cats from 4 countries during the first coronavirus disease wave in Europe. We found 4.4% seroprevalence using a virus neutralization test and 4.3% using a receptor-binding domain ELISA, demonstrating probable human-to-cat transmission.

Time-resolved relaxation and fragmentation of polycyclic aromatic hydrocarbons investigated in the ultrafast XUV-IR regime

Polycyclic aromatic hydrocarbons (PAHs) play an important role in interstellar chemistry and are subject to high energy photons that can induce excitation, ionization, and fragmentation. Previous studies have demonstrated electronic relaxation of parent PAH monocations over 10-100 femtoseconds as a result of beyond-Born-Oppenheimer coupling between the electronic and nuclear dynamics. Here, we investigate three PAH molecules: fluorene, phenanthrene, and pyrene, using ultrafast XUV and IR laser pulses. Simultaneous measurements of the ion yields, ion momenta, and electron momenta as a function of laser pulse delay allow a detailed insight into the various molecular processes. We report relaxation times for the electronically excited PAH^*, PAH^+* and PAH^2+* states, and show the time-dependent conversion between fragmentation pathways. Additionally, using recoil-frame covariance analysis between ion images, we demonstrate that the dissociation of the PAH²⁺ ions favors reaction pathways involving two-body breakup and/or loss of neutral fragments totaling an even number of carbon atoms.

Comparative study of immunohematological tests with canine blood samples submitted for a direct antiglobulin (Coombs') test

BACKGROUND

A 2019 ACVIM consensus statement on diagnostics for immune-mediated hemolytic anemia (IMHA) in dogs made testing recommendations. As data on the performance of immunohematological tests was lacking, we undertook a comparative analysis.

MATERIAL AND METHODS

Anticoagulated blood samples from 126 dogs suspected of having IMHA submitted to a diagnostic veterinary laboratory for a routine direct antiglobulin test (DAT) and from 28 healthy control dogs were evaluated for spherocytosis and autoagglutination before and after three saline washes. Samples were also subjected to different DATs: a gel minitube and an immunochromatographic strip kit used in clinics; neutral gel column cards, microtiter plates (at 4°, 22°, and 37°C), capillary tubes, and flow cytometry used in laboratories.

RESULTS

Samples from healthy dogs yielded negative results with all immunodiagnostic tests. Among the 126 samples submitted for DAT 67 were positive by a DAT utilizing microtiter plates with goat anti-dog antiglobulin DAT at 22°C. Notably, DAT results were comparable and consistent across all evaluated methods regardless of antiglobulin and temperature used. DAT+ dogs were more severely anemic and more likely to have erythroid regeneration compared to DAT- dogs. Macroscopic agglutination in tubes or on slides was observed in 48 samples after 1:1 and 1:4 blood to saline dilution, but only persisted in four samples after washing. Among the DAT+ samples, 57% had agglutination, 87% had spherocytosis, and 45% had both. There was good correlation between spherocytosis and DAT results from the six DAT techniques, but the correlation with autoagglutination was only fair. Clinical follow-up was available for 42 dogs. Of the sample from 12 DAT+ dogs collected during treatment, 10 remained DAT+ when tested 1-24 weeks after initial assessment.

CONCLUSIONS

Based upon this comparative prospective survey, all in-clinic and laboratory DAT techniques produced similar results when performed by trained personnel and can therefore be recommended for detection of antibody-coated erythrocytes and immunohematological diagnosis. In addition, use of these tests for monitoring response of IMHA dogs to treatment might be valuable.

Imaging of retina cellular and subcellular structures using ptychographic hard X-ray tomography

Ptychographic hard X-ray computed tomography (PXCT) is a recent method allowing imaging with quantitative electron-density contrast. Here, we imaged, at cryogenic temperature and without sectioning, cellular and subcellular structures of a chemically fixed and stained wild-type mouse retina, including axons and synapses, with complete isotropic 3D information over tens of microns. Comparison with tomograms of degenerative retina from a mouse model of retinitis pigmentosa illustrates the potential of this method for analyzing disease processes like neurodegeneration at sub-200 nm resolution. As a non-destructive imaging method, PXCT is very suitable for correlative imaging. Within the outer plexiform layer containing the photoreceptor synapses, we identified somatic synapses. We used a small region inside the X-ray-imaged sample for further high-resolution focused ion beam/scanning electron microscope tomography. The subcellular structures of synapses obtained with the X-ray technique matched the electron microscopy data, demonstrating that PXCT is a powerful scanning method for tissue volumes of more than 60 cells and sensitive enough for identification of regions as small as 200 nm, which remain available for further structural and biochemical investigations.

A Single Base Insertion in F9 Causing Hemophilia B in a Family of Newfoundland-Parti Standard Poodle Hybrid Dogs

Hemophilia B is an x-linked recessive hereditary coagulopathy that has been reported in various species. We describe a male Newfoundland–Parti Standard Poodle hybrid puppy and its family with hemophilia B from clinical manifestations to the molecular genetic defect. The index case presented for dyspnea was found to have a mediastinal hematoma, while surgical removal and transfusion support brought some relief, progressive hematoma formations led to humane euthanasia. Sequencing the F9 exons revealed a single nucleotide insertion resulting in a frameshift in the last exon (NM_001003323.2:c.821_822insA), predicted to result in a premature stop codon (NP_001003323.1:p.Asn274LysfsTer23) with a loss of 178 of 459 amino acids. The unexpected high residual plasma factor IX activity (3% to 11% of control) was likely erroneous, but no further studies were performed. Both the purebred Newfoundland dam and her sister were heterozygous for the insertion. Five additional male offspring developed severe hemorrhage and were hemizygous for the F9 variant and/or had a prolonged aPTT. In contrast, other male littermates had normal aPTTs and no evidence of bleeding. While they are related to a common Newfoundland granddam, the prevalence of the pathogenic variant in the Newfoundland breed is currently unknown. These clinical to molecular genetic studies illustrate that precision medicine is achievable in clinical companion animal practice.

[Manganese concentrations in whole blood, plasma and serum of adult warmblood horses from 3 locations in Germany]

OBJECTIVE

This study aimed to establish reference intervals for Mn in whole blood, plasma and serum of healthy, adult warmblood horses with known dietary Mn intake and to compare 2 methods of analysis.

MATERIAL AND METHODS

Between May 2018 and November 2019 a single blood sample was taken from a total of 270 clinically healthy horses (age: 3-25 years) in 3 stud farms. In lithium-heparin (LH) whole blood, LH plasma and serum Mn concentrations were analyzed by means of atomic absorption spectrometry (AAS) and inductively coupled plasma mass spectrometry (ICP-MS). The reference intervals were calculated according to the recommendations of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) and the Clinical and Laboratory Standards Institute (CLSI) comprising the range between 2.5 and 97.5 percentile of the analyzed Mn concentrations. Concurrent to blood sampling feed samples were taken and analyzed in order to determine the Mn content of the corresponding feeding ration.

RESULTS

The horses' whole-blood Mn levels were significantly (p < 0.0001) higher with a median Mn concentration of 12.4 μg/l (reference interval: 4.99-25.1 μg/l [AAS]; 5.99-25.3 μg/l [ICP-MS]) than in the corresponding serum (median: 1.65 μg/l, reference interval: 0.60-3.50 μg/l [AAS]; 1.11-2.96 μg/l [ICP-MS]) or LH plasma (median: 1.35 μg/l, reference interval: 0.22-2.68 μg/l [AAS]; 0.59-2.45 μg/l [ICP-MS]). In the comparison of methods, there were statistically significant differences in the Mn determinations for LH plasma and serum between AAS and ICP-MS, whereas they yielded comparable results for whole blood.

CONCLUSION AND CLINICAL RELEVANCE

Whole blood shows an average of 10-fold higher Mn concentrations than serum or LH plasma. When evaluating blood Mn concentrations, consideration must be granted to the sample material under analysis as well as to which method is employed since relevant differences were found between AAS and ICP-MS in serum and LH plasma.

Anaplasma phagocytophilum in domestic cats from Germany, Austria and Switzerland and clinical/laboratory findings in 18 PCR-positive cats (2008-2020)

OBJECTIVES

Anaplasma phagocytophilum is considered the most significant rickettsial pathogen affecting cats. The organism is transmitted by ticks of the species Ixodes ricinus in Central Europe and can cause granulocytic anaplasmosis in pets, wildlife and humans. The aims of this study were to assess the frequency of positive test results for A phagocytophilum in cats in Germany, Austria and Switzerland, as well as to evaluate clinical and laboratory findings in cats with positive PCR results.

METHODS

This study included the results of direct (PCR) and indirect detection methods (immunofluorescence antibody tests [IFAT]) requested by veterinarians in Germany, Austria and Switzerland between 2008 and 2020 from the LABOKLIN laboratory (Bad Kissingen, Germany). The veterinarians treating the PCR-positive cats were contacted by telephone to enquire about their clinical signs, laboratory findings, management and outcomes.

RESULTS

In total, 244/1636 cats (15%) tested positive by direct (PCR: n = 27/725 [4%]) and/or indirect detection methods (IFAT: n = 221/956 [23%]). In 18/26 cats with PCR results positive for A phagocytophilum, additional information about clinical signs, laboratory findings, treatment and outcome was obtained. Of these 18 cats, five had comorbidities independent of their infection with A phagocytophilum. The most common clinical signs in PCR-positive cats (total/without comorbidities) were lethargy (83%/92%), fever (83%/85%) and thrombocytopenia (61%/62%). Overall, more than half (57%) of the cats with and without comorbidities recovered clinically.

CONCLUSIONS AND RELEVANCE

Infections with A phagocytophilum should be considered as differential diagnoses in cats with tick infestation, lethargy, fever and thrombocytopenia. The clinical signs and laboratory findings are consistent with published case reports in cats. Ectoparasite prophylaxis in cats is recommended throughout the entire year.

Serum NMR metabolomics uncovers multiple metabolic changes in phenobarbital-treated dogs

INTRODUCTION

Phenobarbital is a commonly used anticonvulsant for the treatment of canine epileptic seizures. In addition to its central nervous system (CNS) depressing effects, long-term phenobarbital administration affects liver function. However, broader metabolic consequences of phenobarbital treatment are poorly characterized.

OBJECTIVES

To identify metabolic changes in the sera of phenobarbital-treated dogs and to investigate the relationship between serum phenobarbital concentration and metabolite levels.

METHODS

Leftovers of clinical samples were used: 58 cases with phenobarbital concentrations ranging from 7.8 µg/mL to 50.8 µg/mL, and 25 controls. The study design was cross-sectional. The samples were analyzed by a canine-specific 1H NMR metabolomics platform. Differences between the case and control groups were evaluated by logistic regression. The linear relationship between metabolite and phenobarbital concentrations was evaluated using linear regression.

RESULTS

Increasing concentrations of glycoprotein acetyls, LDL particle size, palmitic acid, and saturated fatty acids, and decreasing concentrations of albumin, glutamine, histidine, LDL particle concentration, multiple HDL measures, and polyunsaturated fatty acids increased the odds of the sample belonging to the phenobarbital-treated group, having a p-value < .0033, and area under the curve (AUC) > .7. Albumin and glycoprotein acetyls had the best discriminative ability between the groups (AUC: .94). No linear associations between phenobarbital and metabolite concentrations were observed.

CONCLUSION

The identified metabolites are known to associate with, for example, liver and CNS function, inflammatory processes and drug binding. The lack of a linear association to phenobarbital concentration suggests that other factors than the blood phenobarbital concentration contribute to the magnitude of metabolic changes.