Using data-driven approaches to improve delivery of animal health care interventions for public health.

Rabies kills ∼60,000 people per year. Annual vaccination of at least 70% of dogs has been shown to eliminate rabies in both human and canine populations. However, delivery of large-scale mass dog vaccination campaigns remains a challenge in many rabies-endemic countries. In sub-Saharan Africa, where the vast majority of dogs are owned, mass vaccination campaigns have typically depended on a combination of static point (SP) and door-to-door (D2D) approaches since SP-only campaigns often fail to achieve 70% vaccination coverage. However, D2D approaches are expensive, labor-intensive, and logistically challenging, raising the need to develop approaches that increase attendance at SPs. Here, we report a real-time, data-driven approach to improve efficiency of an urban dog vaccination campaign. Historically, we vaccinated ∼35,000 dogs in Blantyre city, Malawi, every year over a 20-d period each year using combined fixed SP (FSP) and D2D approaches. To enhance cost effectiveness, we used our historical vaccination dataset to define the barriers to FSP attendance. Guided by these insights, we redesigned our vaccination campaign by increasing the number of FSPs and eliminating the expensive and labor-intensive D2D component. Combined with roaming SPs, whose locations were defined through the real-time analysis of vaccination coverage data, this approach resulted in the vaccination of near-identical numbers of dogs in only 11 d. This approach has the potential to act as a template for successful and sustainable future urban SP-only dog vaccination campaigns.

Dog Ownership in Early Life Increased the Risk of Nonatopic Asthma in Children.

BACKGROUND: It is still debatable whether dog ownership during early childhood is a risk factor for the development of allergic diseases. OBJECTIVE: We investigated the association of dog ownership in early life with sensitization and asthma in childhood. METHODS: Data from the Cohort for Childhood Origin of Asthma and Allergic diseases were used to investigate the association between dog ownership at any time from pregnancy to 1 year of age and sensitization to aeroallergens at 3 and 7 years old, bronchial hyperresponsiveness (BHR), and asthma at 7 years old. We analyzed the cytokine levels in cord blood (CB) and indoor environmental measurement concentrations in the mother's residence obtained at 36 weeks of pregnancy. RESULTS: Sensitization to dogs at age 3 and 7 did not differ between dog ownership and nonownership, but dog ownership during early life decreased the risk of sensitization to aeroallergens at age 7 (aOR = 0.44, 95% CI 0.21-0.90). Dog ownership significantly increased the risk of nonatopic BHR (aOR = 2.86; 95% CI 1.32-6.21). In addition, dog ownership was associated with asthma, especially nonatopic asthma at 7 years old (aOR = 2.73, 95% CI 1.02-7.32; aOR = 7.05, 95% CI 1.85-26.90, respectively). There were no significant differences in the concentrations of IL-13 or interferon-γ in CB or indoor environmental measurements according to dog ownership during pregnancy. CONCLUSION: Early-life dog exposure in this birth cohort has been shown to reduce atopy but increase the risk of nonatopic BHR and nonatopic asthma at 7 years old.

Prevalence of Dal blood type and dog erythrocyte antigens (DEA) 1, 4, and 7 in canine blood donors in Italy and Spain.

BACKGROUND: The aim of this study was to determine the prevalence of Dal, and DEA 1, 4, 7 blood types, in a population of canine blood donors from Italy and Spain. Three hundred and twenty blood donor dogs receiving an annual health evaluation were included in the study. DEA 1 blood type was determined using an immunochromatographic strip technique while Dal, DEA 4 and 7 blood types were determined with polyclonal antisera using agglutination on gel columns. RESULTS: Out of 320 dogs blood typed 7 (2 Cane Corso and 5 Doberman Pinschers) (2.2%) were Dal negative; 137 (42.8%) were positive for DEA 1; 320 (100%) were positive for DEA 4 and 43 (13.4%) were positive for DEA 7. CONCLUSION: This study showed a similar prevalence of DEA 1, 7 and 4 to that reported in previous studies in the same, and in different, geographic areas, and provides new data on the prevalence of the Dal blood group in Italy and Spain. There was no significant difference (P = 0.8409) between prevalence of Dal negative blood types found in our population (2.2%) and the prevalence reported in a canine blood donor population from the USA (2.5%). Our study identified Dal negative dogs in a previously tested breed i.e. Doberman Pinschers, but also the Cane Corso breed was found to have Dal negative dogs.

Profile of gamma-delta (γδ) T lymphocytes in the peripheral blood of crossbreed dogs during stages of life and implication in aging.

BACKGROUND: Data on gamma-delta (γδ) T lymphocytes in the peripheral blood of dogs are scant, related only to healthy pure breed dogs and limited to a restricted age range. The aim of the study was to investigate the modulation of the γδ T lymphocyte (TCRγδ+) subpopulation in peripheral blood of crossbreed healthy dogs according to five identified stages of life: Puppy, Junior, Adult, Mature, Senior and to determine its implication in aging. A rigorous method of recruitment was used to minimize the influence of internal or external pressure on the immune response. Twenty-three intact female and twenty-four intact male dogs were enrolled. Blood samples were collected and immunophenotyping of peripheral blood T lymphocytes and γδ T cell subpopulations was performed. RESULTS: The percentage of γδ T cells in peripheral blood lymphocytes was comparable with the value of 2.5% published by Faldyna and co-workers (2001), despite the percentage reported was investigated in less arranged age range groups and coming from four different dog pure breeds, whereas our data were recorded on wider age range groups and coming from crossbreed dogs. Therefore, the γδ T cell percentage (2.5%) is consistent and points out that such value is breed-independent. Statistical analysis highlighted differences in both percentage and absolute γδ T cells according to the stage of life. γδ T cells decreased significantly in the peripheral blood of elder dogs (Senior group) in comparison with previous stages of life (Puppy, Junior, and Adult groups). Differences in γδ T cells are significant and they are reported, for the first time, related to dog aging. CONCLUSIONS: The study confirms dogs to be among the animals with a low TCRγδ+ cell profile. A decrease of the TCRγδ+ subpopulation percentage was observed in elder dogs. TCRγδ+ cells of group S were different from those of groups P, J, and A. The differences are reported for the first time in dog aging. Identifying the stage of life when the decrease of γδ T lymphocytes starts can be useful for providing a rationale for drafting a wellness plan trial to support thymus immune functions and mitigate its functional exhaustion.

Asthma prevalence, but not allergic rhinitis nor atopic dermatitis, is associated to exposure to dogs in adolescents.

BACKGROUND: Exposure to pets can be a predisposing factor in the development of certain diseases, including allergic diseases. OBJECTIVE: We analyzed the role that exposure to indoor dogs and cats plays in the prevalence of allergic diseases. METHODS: We examined the cross-sectional data of 1056 women and 936 men aged 15 to 18 years; these individuals were selected through stratified and cluster random sampling. We asked all participants about their exposure to indoor dogs and cats during the year that preceded our study. The prevalence of allergic diseases was determined through core questions taken from The International Study of Asthma and Allergies in Childhood questionnaire. RESULTS: The prevalence was 12.7% (95% CI: 11.3%-14.2%) for asthma, 9.0% (95% CI: 7.8%-10.4%) for allergic rhinitis, and 5.2% (95% CI: 4.3%-6.2%) for atopic dermatitis. The multivariate analyses showed that exposure to indoor dogs, but not indoor cats, was associated with asthma prevalence (aOR 1.37; 95% CI: 1.03-1.83), as was male sex (aOR=1.42; 95% CI: 1.08-1.86), a personal history of allergic rhinitis (aOR=3.24; 95% CI: 2.25-4.66), and a maternal history of asthma (aOR=3.06; 95% CI: 1.89-4.98). The population attributable risk for exposure to indoor dogs was 18%. Notably, neither allergic rhinitis nor atopic dermatitis was found to be associated with dog or cat exposure (p> 0.05). CONCLUSION: Exposure to dogs in late adolescence is a factor associated with asthma, although its contribution to the development of asthma should be investigated in new studies.

An investigation of cross-reactivity between the poultry red mite and house dust and storage mites in dogs with contact with chickens infested with red mites.

BACKGROUND: The European poultry red mite (PRM) Dermanyssus gallinae, a common ectoparasite of laying chickens and pigeons; it also can feed on other birds, humans and domestic animals, causing clinical signs ranging from mild discomfort to severe dermatitis. Little is known about possible hypersensitivity to PRM or cross-sensitization with house dust or storage mites. HYPOTHESIS/OBJECTIVES: Knowledge on possible PRM immunoglobulin E (IgE)-mediated allergy and possible cross-sensitization with house dust and storage mites may facilitate the clinical approach. The aim herein was to clarify possible evidence of type I hypersensitivity to PRM in dogs and possible occurrence of cross-sensitization with house dust and storage mites. ANIMALS: Sixteen dogs with chronic contact with PRM-infested chickens from traditional bird houses and 10 control dogs with no contact with birds. METHODS AND MATERIALS: Dogs were subjected to intradermal testing (IDT) and serum specific IgE (sIgE) determination for house dust and storage mites and D. gallinae. RESULTS: The highest wheal score was obtained with 0.1 mg/mL D. gallinae extract. Positive IDT reactions to PRM were found in four of 10 control dogs and in 10 of 16 from the chicken-exposed group. SIgE to PRM was detected in one control and in seven dogs exposed to chickens. No significant correlation was found between IDT or sIgE scores to PRM and house dust and storage mites. CONCLUSIONS AND CLINICAL SIGNIFICANCE: Contact with PRM-infested chickens may lead to sensitization without allergy, independently from sensitization to house dust and storage mites.

Whole-Genome Sequencing of African Dogs Provides Insights into Adaptations against Tropical Parasites.

Natural selection in domestic dogs is of great interest in evolutionary biology since dogs have migrated to every inhabited continent of the world alongside humans, and adapted to diverse environments. Here, we explored their demographic history and genetic basis of adaptation to the tropical African environment using whole genome analyses of 19 African indigenous dogs from Nigeria. Demographic analysis suggests that the ancestors of these dogs migrated into Africa from Eurasia 14,000 years ago and underwent a severe founder effect before population expansion. Admixture analysis further reveals that African dog genomes contain about 1.88-3.50% introgression from African golden wolves (Canis anthus). Population genetic analysis identifies 50 positively selected genes linked with immunity, angiogenesis, ultraviolet protection, as well as insulin secretion and sensitivity that may contribute to adaptation to tropical conditions. One of the positively selected genes, adhesion G protein-coupled receptor E1 (ADGRE1), has also been found to be association with severe malaria resistance in African human populations. Functional assessments showed that ADGRE1 provides protective host defense against Plasmodium infections. This result, together with the fact that the inflammatory response to canine babesiosis is similar to complicated falciparum malaria in humans, support the dogs as a model for the study of malaria control and treatment.

Systemic reactions to subcutaneous immunotherapy: Effects of dosing and aeroallergen content.

BACKGROUND: Systemic reactions are a known risk of subcutaneous immunotherapy (SCIT) for aeroallergens. OBJECTIVE: To identify the dose of SCIT that results in the most systemic reactions to SCIT (SCITSRs) and other risk factors for SCITSRs. METHODS: We performed a retrospective review of all SCIT encounters from 2013 to 2017 at a multisite allergy/immunology practice. SCITSRs were identified from the electronic health record through immunotherapy encounters in which epinephrine was administered. Collected data included patient demographics, the dose of immunotherapy at the time of the SCITSR, the presence or absence of asthma, and aeroallergen content. The control group was generated randomly from the same cohort during the same period. RESULTS: There were 86,949 SCIT visits, with 81 SCITSRs (0.9 per 1000 injections). A total of 77.8% of reactions occurred at a dose of 1:1 0.1 mL and above. The presence of cat (81.5% vs 63.0%, P = .01), dog (67.9% vs 37.0%, P < .001), and grass extracts (85.2% vs 67.5%, P = .01) were associated with SCITSRs. Asthma was not significantly associated with SCITSRs. The presence of dust mites, trees, weeds, and molds was not associated with SCITSRs. There were no months or seasons where SCITSRs were more likely to occur. Individuals who experienced SCITSRs had a mean (SD) higher number of included aeroallergenic groups compared with controls (5.86 [1.88] vs 5.00 [1.92], P < .001). CONCLUSION: Risk factors for SCITSRs in a multisite allergy/immunology practice included administration of the highest immunotherapy doses; inclusion of cat, dog, and grass extracts; and the number of aeroallergenic groups included in the extract. This information helps further characterize risk for patients receiving SCIT.

Local immune and microbiological responses to mucosal administration of a Liposome-TLR agonist immunotherapeutic in dogs.

BACKGROUND: Non-specific immunotherapeutics have been evaluated previously in dogs, primarily for cancer treatment. However, there remains a need for a more broadly targeted, general purpose immunotherapeutic capable of activating innate immune defenses for non-specific protection or early treatment of viral and bacterial infections. To address need, our group has developed a liposomal immune stimulant (liposome-TLR complexes, LTC) containing TLR 3 and 9 agonists specifically designed to activate mucosal immune defenses in sites such as nasal cavity and oropharynx, following topical delivery. In this study, we evaluated the local immune stimulatory properties of LTC in vitro and in healthy purpose-bred dogs, including activation of cellular recruitment and cytokine production. The ability of LTC treatment to elicit effective antiviral immunity was assessed in dogs following a canine herpesvirus outbreak, and the impact of LTC treatment on the local microbiome of the oropharynx was also investigated. RESULTS: These studies revealed that LTC potently activated innate immune responses in vitro and triggered significant recruitment of inflammatory monocytes and T cells into the nasal cavity and oropharynx of healthy dogs. Administration of LTC to dogs shortly after an outbreak of canine herpesvirus infection resulted in significant reduction in clinical signs of infection. Interestingly, administration of LTC to healthy dogs did not disrupt the microbiome in the oropharynx, suggesting resiliency of the microflora to transient immune activation. CONCLUSIONS: Taken together, these results indicate that LTC administration mucosally to dogs can trigger local innate immune activation and activation of antiviral immunity, without significantly disrupting the composition of the local microbiome. Thus, the LTC immune stimulant has potential for use as a non-specific immunotherapy for prevention or early treatment of viral and bacterial infections in dogs.

Longitudinal monitoring of anti-saliva antibodies as markers of repellent efficacy against Phlebotomus perniciosus and Phlebotomus papatasi in dogs.

A 2-year longitudinal study of enzyme-linked immunosorbent assay (ELISA) antibodies against Phlebotomus perniciosus and Phlebotomus papatasi (Diptera: Psychodidae) sandfly saliva was performed in 32 Beagle dogs treated preventively with an imidacloprid-permethrin topical insecticide in an endemic area in Spain. Dogs were grouped into three sandfly exposure groups according to the time of inclusion in the study. Assays analysed immunoglobulin G (IgG) against salivary gland homogenates (SGH) of both species and recombinant P. papatasi rSP32 and P. perniciosus rSP03B proteins in serum. The dogs were participating in a Leishmania infantum (Kinetoplastida: Trypanosomatidae) vaccine trial and were experimentally infected with the parasite in the second year. No dog acquired natural L. infantum infections during the first year, but most developed anti-saliva antibodies, and median log-transformed optical densities (LODs) were seasonal, mimicking those of local sandflies. This indicates that the repellent efficacy of the insecticide used is below 100%. Multi-level modelling of LODs revealed variability among dogs, autocorrelation and differences according to the salivary antigen and the dog's age. However, dog seroprevalence, estimated using pre-exposure LODs as cut-offs, was relatively low. This, and the fact that dogs did not become naturally infected with L. infantum, would support the efficacy and usefulness of this imidacloprid-permethrin topical insecticide in canine leishmaniasis control.

What is the real number of Lyme disease cases in Canada?

BACKGROUND: Lyme disease is emerging in Canada due to expansion of the range of the tick vector Ixodes scapularis from the United States. National surveillance for human Lyme disease cases began in Canada in 2009. Reported numbers of cases increased from 144 cases in 2009 to 2025 in 2017. It has been claimed that few (< 10%) Lyme disease cases are reported associated with i) supposed under-diagnosis resulting from perceived inadequacies of serological testing for Lyme disease, ii) expectation that incidence in Canadian provinces and neighbouring US states should be similar, and iii) analysis of serological responses of dogs to the agent of Lyme disease, Borrelia burgdorferi. We argue that performance of serological testing for Lyme disease is well studied, and variations in test performance at different disease stages are accounted for in clinical diagnosis of Lyme disease, and in surveillance case definitions. Extensive surveillance for tick vectors has taken place in Canada providing a clear picture of the emergence of risk in the Canadian environment. This surveillance shows that the geographic scope of I. scapularis populations and Lyme disease risk is limited but increasing in Canada. The reported incidence of Lyme disease in Canada is consistent with this pattern of environmental risk, and the differences in Lyme disease incidence between US states and neighbouring Canadian provinces are consistent with geographic differences in environmental risk. Data on serological responses in dogs from Canada and the US are consistent with known differences in environmental risk, and in numbers of reported Lyme disease cases, between the US and Canada. CONCLUSION: The high level of consistency in data from human case and tick surveillance, and data on serological responses in dogs, suggests that a high degree of under-reporting in Canada is unlikely. We speculate that approximately one third of cases are reported in regions of emergence of Lyme disease, although prospective studies are needed to fully quantify under-reporting. In the meantime, surveillance continues to identify and track the ongoing emergence of Lyme disease, and the risk to the public, in Canada.

Serum IgE cross-reactivity between fish and chicken meats in dogs.

BACKGROUND: In humans, a cross-reactive clinical allergy has been reported between three chicken and fish meat proteins: beta-enolase, aldolase A and parvalbumin. OBJECTIVE: To evaluate if IgE cross-reactivity between chicken and fish also existed in the dog. ANIMALS: Sera from dogs with suspected allergic skin disease and with IgE against chicken and fish. METHODS AND MATERIALS: Sera were analysed by ELISA and immunoblotting with chicken, white fish (haddock and cod) and salmon extracts. Reciprocal inhibition ELISAs and inhibition immunoblots were then performed. Protein sequencing of bands identified on multiple extracts was determined by mass spectrometry. RESULTS: Out of 53 archived canine sera tested by ELISA against chicken, white fish or salmon, 15 (28%), 12 (23%) and 26 (49%), respectively, had elevated IgE against one, two or all three of these extracts. Seven of the triple-reactive sera were subjected to reciprocal inhibition ELISAs. A >50% inhibition was found between chicken-fish, chicken-salmon and fish-salmon in seven, four and five of seven dogs, respectively. Immunoblotting identified multiple IgE-binding proteins of identical molecular weights in the three extracts; these were partially to fully cross-reactive by inhibition immunoblotting. Mass spectrometry identified nine cross-reactive proteins as: pyruvate kinase, creatine kinase, alpha-actin, glyceraldehyde-3-phosphate dehydrogenase, beta-enolase, aldolase, malate dehydrogenase, lactate dehydrogenase and triose-phosphate isomerase 1. All of these have been reported previously as fish, shellfish and/or chicken allergens for humans. CONCLUSIONS AND CLINICAL IMPORTANCE: Whether any of these newly identified IgE cross-reactive chicken-fish allergens is the cause of clinical allergy needs to be determined in dogs reacting to at least two of these common food sources.

Prevalence of antibodies against Toxoplasma gondii in pets and their owners in Shandong province, Eastern China.

BACKGROUND: Pet ownership in China has been steadily increasing over recent years. However, the risk of pet-associated zoonotic infection with the protozoan parasite Toxoplasma gondii remains poorly defined. METHODS: In a cross-sectional survey, we have determined the seroprevalence of T. gondii infection in pet dogs and cats, and pet owners. Serum samples were collected from 360 pets and 460 corresponding pet owners between March 2016 to June 2017, from Shandong province, eastern China. Sera from the animals were tested for anti-T. gondii antibodies using an indirect haemagglutination assay (IHA) and from the pet owners using an enzyme-linked immunosorbent assay (ELISA). RESULTS: Antibodies against T. gondii were detected in 67 of 360 (18.61%) pets. Seroprevalence of T. gondii in pet cats and dogs was 21.67% and 15.56%, respectively. IgG and IgM antibodies were detected in 79 (17.17%) and 4 (0.87%) of pet owners, respectively; with a total of 83 of 460 (18.04%) pet owners testing seropositive for T. gondii. Our seroprevalence data also suggest that cat owners in general and female pet owners in particular could face a higher risk of acquiring T. gondii infection. CONCLUSIONS: Significant levels of anti-T. gondii antibodies were detected in the pets and their owners in Shandong province, eastern China, indicating a potential zoonotic risk. Prophylactic measures should be implemented to reduce the risk of pet owner's exposure to T. gondii infection.

Diversified Anchoring Features the Peptide Presentation of DLA-88*50801: First Structural Insight into Domestic Dog MHC Class I.

Canines represent a crucial animal model for studying human diseases and organ transplantation, as well as the evolution of domestic animals. MHCs, with a central role in cellular immunity, are commonly used in the study of dog population genetics and genome evolution. However, the molecular basis for the peptide presentation of dog MHC remains largely unknown. In this study, peptide presentation by canine MHC class I DLA-88*50801 was structurally determined, revealing diversified anchoring modes of the binding peptides. Flexible and large pockets composed of both hydrophobic and hydrophilic residues can accommodate pathogen-derived peptides with diverse anchor residues, as confirmed by thermostability measurements. Furthermore, DLA-88*50801 contains an unusual α2 helix with a large coil in the TCR contact region. These results further our understanding of canine T cell immunity through peptide presentation of MHC class I and shed light on the molecular basis for vaccine development for canine infectious diseases, for example, canine distemper virus.

Characterization of Anti- Dal Alloantibodies Following Sensitization of Two Dal-Negative Dogs.

Since its discovery, the immunogenicity of the Dal blood type has not been further investigated. The aim of this study was to better characterize anti- Dal alloantibodies produced following sensitization of Dal-negative dogs, notably their rate of appearance, the agglutination titer over time, and their immunoglobulin class. A secondary objective was to obtain polyclonal anti- Dal alloantibodies to increase the availability of Dal blood typing. Of 100 healthy laboratory Beagles tested, 2 Dal-negative dogs were identified as recipients. Ten healthy Dal-positive dogs were investigated as potential blood donors. All dogs were extensively blood typed for DEA 1, 3, 4, 5, and 7, as well as for Dal. Then, the recipients were transfused uneventfully with 10 ml/kg of Dal-positive but otherwise compatible packed red blood cells. Posttransfusion blood samples were collected routinely over a minimum of 1 year. Using a gel column technology, anti- Dal alloantibodies were detected as early as 4 days posttransfusion and remained detectable 2 years posttransfusion, with maximum agglutination titers reached at 1 and 2 months posttransfusion. The immunoglobulin class was IgG. The immunogenicity and clinical significance of the Dal blood type were confirmed. The results support the recommendations that previously transfused dogs be crossmatched starting 4 days posttransfusion and for the animal's lifetime. The polyclonal anti- Dal antibodies produced will allow blood typing of a significant number of dogs, especially transfused dogs facing blood incompatibilities and canine blood donors.

General and type 2 parvovirus-specific passive immune transfer in puppies - Evaluation by early growth.

Failure of passive immune transfer put puppies at a higher risk of neonatal and weaning mortality due to low immune protection against infectious agents. The aim of this study was to investigate the evolution of the general via serum IgG concentration (IgG) and the specific via serum maternally derived canine parvovirus type 2-specific antibody titer (CPV2 MDA) passive immune transfer within the first 4 weeks of age. Furthermore, the relationship between general and specific immune transfer and the possibility of non-invasive evaluation was assessed. Puppies (169) were weighed systematically between birth and Day 28. IgG and CPV2 MDA were assayed in serum samples at 2 and at 28 days of age. At Day 2, there was a positive correlation between IgG and CPV2 MDA (ρ = 0.71; p < 0.001). At Day 2, 17.9% (27/151) of puppies presented a deficit of passive immune transfer according to IgG result (defined as IgG < 2.3 g/L) and 25.8% (39/151) of puppies were under the minimal protective CPV2 MDA titer (defined as <1:160). No correlation between IgG and CPV2 MDA was observed at Day 28 (ρ = 0.14; p = 0.11). Growth rate within the first 48 hours <-2.7% allowed to distinguish puppies at high risk of the general and specific passive immune failure (Youden's index = 0.79 and 0.75, respectively). The threshold value of early growth rate, although applicable only in puppies non-supplemented with milk replacer, allows identifying via non-invasive way individuals requiring a special care. Further investigation of the mechanism of passive immune transfer in dogs is necessary to understand the relationship between the general and specific immunoglobulin levels.

An evaluation of veterinary allergen extract content and resultant canine intradermal threshold concentrations.

BACKGROUND: Limited information is available for dogs on threshold concentrations (TCs), and the protein composition of common allergenic extracts produced by different manufacturers. HYPOTHESIS/OBJECTIVES: To characterize the protein heterogeneity of tree, grass, weed and mite allergens from different lots of allergenic extracts, and to determine intradermal TCs for healthy dogs using extracts from two manufacturers. ANIMALS: Twenty five privately owned, clinically healthy dogs and ten purpose-bred beagle dogs. METHODS AND MATERIALS: Protein concentration and heterogeneity of 11 allergens from two manufacturers were evaluated using a Bradford-style assay and SDS-PAGE. Intradermal testing was performed with 11 allergens from each company at four dilutions. Immediate reactions were subjectively scored (0 to 4+), and objectively measured (mm) and their percentage concordance evaluated. Model-based TCs were determined by fitting positive reactions (≥2+) at 15 min to generalized estimating equations. RESULTS: Allergen extract protein quantity and composition varied within and between manufacturers despite sharing the same PNU/mL values. Model-based TCs of one weed, five trees, two grasses and a house dust mite were determined for extracts from Manufacturer 1 (M1), and for extracts of three weeds, three trees and two grasses from Manufacturer 2 (M2). Receiver operating characteristic curve analyses determined a percentage concordance of the objective and subjective measurements of 77.3% for M1 and 75% for M2 allergens. CONCLUSIONS AND CLINICAL IMPORTANCE: Veterinary allergen extracts labelled as the same species and PNU/mL are not standardized; they show heterogeneity in composition and potency within and between manufacturers. Variability in extract content may require adjustment of intradermal testing concentrations.

Circulating CD4(+)CD25(+)Foxp3(+) T regulatory cell levels in an experimental model of canine atopic dermatitis.

BACKGROUND: The pathogenesis of canine atopic dermatitis (cAD) is characterized immunologically by an imbalanced T-cell response. Mechanisms of immune regulation in cAD have not yet been completely elucidated. OBJECTIVES: To investigate peripheral blood T regulatory (Treg) cells and their associated cytokines (TGF-ß and IL-10) in an experimental model of cAD. ANIMALS: Eight beagle dogs that were initially naïve and subsequently sensitized to house dust mites (HDM). METHODS AND MATERIALS: T regulatory cell phenotyping was performed by flow-cytometric analysis on peripheral blood; serum cytokine levels were measured by ELISA, before sensitization and after challenge with HDM allergens. Additionally, clinical scores and allergen-specific IgE were determined. RESULTS: After challenge of sensitized dogs to HDM allergen, a significant increase of Treg cells and simultaneous decrease in the serum TGF-ß were observed. However, in most dogs, serum IL-10 values were below the detection limit. Treg cell proportions before sensitization were significantly negatively correlated with the HDM-specific IgE levels and clinical scores after induction of AD signs. CONCLUSION AND CLINICAL IMPORTANCE: The results confirm that Treg responses are involved in the pathogenesis of an experimental model cAD. Further investigations are required to clarify the precise immune modulating function of canine Treg cells and their interplay with other immune cell types.

Anaplasmataceae agents among wild mammals and ectoparasites in Brazil.

Anaplasmataceae agents comprise obligate intracellular bacteria that can cause disease in humans and animals. Between August 2013 and March 2015, 31 Nasua nasua (coati), 78 Cerdocyon thous (crab-eating fox), seven Leopardus pardalis (ocelot), 110 wild rodents, 30 marsupials, and 42 dogs were sampled in the Pantanal wetland, Brazil. In addition, ectoparasites found parasitizing the animals were collected and identified. The present work aimed to investigate the occurrence of Anaplasmataceae agents in wild mammals, domestic dogs and ectoparasites, by molecular and serological techniques. Overall, 14 (17·9%) C. thous, seven (16·6%) dogs and one (3·2%) N. nasua were seroreactive to Ehrlichia canis. Nine dogs, two C. thous, one N. nasua, eight wild rodents, five marsupials, eight Amblyomma sculptum, four Amblyomma parvum, 13 A. sculptum nymphal pools, two Amblyomma larvae pools and one Polygenis (Polygenis) bohlsi bohlsi flea pool were positive for Ehrlichia spp. closely related to E. canis. Seven N. nasua, two dogs, one C. thous, one L. pardalis, four wild rodents, three marsupials, 15 A. sculptum, two Amblyomma ovale, two A. parvum and one Amblyomma spp. larval pools were positive for Anaplasma spp. closely related to A. phagocytophilum or A. bovis. The present study provided evidence that wild animals from Brazilian Pantanal are exposed to Anaplasmataceae agents.