High prevalence of SARS-CoV-2 antibodies and low prevalence of SARS-CoV-2 RNA in cats recently exposed to human cases.

BACKGROUND: The primary objective of this cross-sectional study, conducted in Québec and Bristish Columbia (Canada) between February 2021 and January 2022, was to measure the prevalence of viral RNA in oronasal and rectal swabs and serum antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) amongst cats living in households with at least one confirmed human case. Secondary objectives included a description of potential risk factors for the presence of SARS-CoV-2 antibodies and an estimation of the association between the presence of viral RNA in swabs as well as SARS-CoV-2 antibodies and clinical signs. Oronasal and rectal swabs and sera were collected from 55 cats from 40 households at most 15 days after a human case confirmation, and at up to two follow-up visits. A RT-qPCR assay and an ELISA were used to detect SARS-CoV-2 RNA in swabs and serum SARS-CoV-2 IgG antibodies, respectively. Prevalence and 95% Bayesian credibility intervals (BCI) were calculated, and associations were evaluated using prevalence ratio and 95% BCI obtained from Bayesian mixed log-binomial models. RESULTS: Nine (0.16; 95% BCI = 0.08-0.28) and 38 (0.69; 95% BCI = 0.56-0.80) cats had at least one positive RT-qPCR and at least one positive serological test result, respectively. No risk factor was associated with the prevalence of SARS-CoV-2 serum antibodies. The prevalence of clinical signs suggestive of COVID-19 in cats, mainly sneezing, was 2.12 (95% BCI = 1.03-3.98) times higher amongst cats with detectable viral RNA compared to those without. CONCLUSIONS: We showed that cats develop antibodies to SARS-CoV-2 when exposed to recent human cases, but detection of viral RNA on swabs is rare, even when sampling occurs soon after confirmation of a human case. Moreover, cats with detectable levels of virus showed clinical signs more often than cats without signs, which can be useful for the management of such cases.

Effects of fixation and demineralization on histomorphology and DNA amplification of canine bone marrow.

Fixation and demineralization protocols for bone marrow (BM) across diagnostic laboratories are not standardized. How different protocols affect histomorphology and DNA amplification is incompletely understood. In this study, 2 fixatives and 3 demineralization methods were tested on canine BM samples. Twenty replicate sternal samples obtained within 24 hours of death were fixed overnight in either acetic acid-zinc-formalin (AZF) or 10% neutral-buffered formalin (NBF) and demineralized with formic acid for 12 hours. Another 53 samples were fixed in AZF and demineralized with hydrochloric acid for 1-hour, formic acid for 12 hours, or ethylenediamine tetraacetic acid (EDTA) for 24 hours. Histologic sections were scored by 4 raters as of insufficient, marginal, good, or excellent quality. In addition, DNA samples extracted from sections treated with the different fixation and demineralization methods were amplified with 3 sets of primers to conserved regions of T cell receptor gamma and immunoglobulin heavy chain genes. Amplification efficiency was graded based on review of capillary electrophoretograms. There was no significant difference in the histomorphology scores of sections fixed in AZF or NBF. However, EDTA-based demineralization yielded higher histomorphology scores than demineralization with hydrochloric or formic acid, whereas formic acid resulted in higher scores than hydrochloric acid. Demineralization with EDTA yielded DNA amplification in 29 of 36 (81%) samples, whereas demineralization with either acid yielded amplification in only 2 of 72 (3%) samples. Although slightly more time-consuming and labor-intensive, tissue demineralization with EDTA results in superior morphology and is critical for polymerase chain reaction (PCR) amplification with the DNA extraction method described in this article.

Diagnosis and management of a peripheral T-cell lymphoproliferative disease in an American pine marten (Martes americana).

A 9-year-old neutered male American pine marten (Martes americana) was referred for further evaluation of suspected lymphoproliferative disease. On physical examination, the pine marten was determined to be in an underconditioned state with an enlarged right mandibular lymph node. Hematology revealed a marked leukocytosis characterized by a lymphocytosis. Flow cytometry performed on peripheral blood was suggestive of a CD4+ T-cell lymphoproliferative disease. Whole-body radiographs demonstrated a large cranial mediastinal mass and splenomegaly. These findings were confirmed using ultrasound, which also identified intra-abdominal lymphadenopathy and splenic nodules. Cytologic evaluation of aspirates from the mediastinal mass was interpreted as possible lymphoma. The pine marten was treated with chlorambucil and prednisolone and achieved a durable partial remission. Twelve months after initial diagnosis, progressive disease was noted and treatment with lomustine was initiated as a rescue protocol until euthanasia, which was carried out 15 mo after the initial diagnosis. Based on a literature search, this is the first case report describing the management of peripheral T-cell lymphoproliferative disease, presumably peripheral lymphoma, in a pine marten; this neoplasm should be considered as a differential diagnosis in pine martens that have abnormal complete blood cell count findings and enlarged lymph nodes. Key clinical message: This report describes the diagnosis and management of a peripheral T-cell lymphoproliferative disease, presumably peripheral lymphoma, in an American pine marten (Martes americana). This is the first report of this disease and its successful treatment in a pine marten.

Diagnostic et prise en charge d'une maladie lymphoproliférative à cellules T périphériques chez une martre d'Amérique ( Martes americana ). Une martre d'Amérique (Martes americana) mâle castré âgé de 9 ans a été référée pour une évaluation plus approfondie d'une suspicion de maladie lymphoproliférative. À l'examen physique, il a été déterminé que la martre était dans un état sous-optimal avec un ganglion lymphatique mandibulaire droit élargi. L'hématologie a révélé une hyperleucocytose marquée caractérisée par une lymphocytose. La cytométrie en flux réalisée sur le sang périphérique était évocatrice d'une maladie lymphoproliférative des lymphocytes T CD4+. Les radiographies du corps entier ont montré une importante masse médiastinale crânienne et une splénomégalie. Ces résultats ont été confirmés par échographie, qui a également identifié une lymphadénopathie intra-abdominale et des nodules spléniques. L'évaluation cytologique des aspirations de la masse médiastinale a été interprétée comme un possible lymphome. La martre d'Amérique a été traitée avec du chlorambucil et de la prednisolone et une rémission partielle durable a été obtenue. Douze mois après le diagnostic initial, une progression de la maladie a été notée et un traitement par lomustine a été initié comme protocole de sauvetage jusqu'à l'euthanasie, qui a été réalisée 15 mois après le diagnostic initial. Sur la base d'une recherche documentaire, il s'agit du premier rapport de cas décrivant la prise en charge d'une maladie lymphoproliférative périphérique à cellules T, vraisemblablement un lymphome périphérique, chez une martre d'Amérique; ce néoplasme doit être considéré comme un diagnostic différentiel chez les martres d'Amérique qui présentent des résultats anormaux de numération globulaire complète et des ganglions lymphatiques hypertrophiés.Message clinique clé :Ce rapport décrit le diagnostic et la prise en charge d'une maladie lymphoproliférative à cellules T périphériques, vraisemblablement un lymphome périphérique, chez une martre d'Amérique (Martes americana). Il s'agit du premier signalement de cette maladie et de son traitement réussi chez une martre d'Amérique.(Traduit par Dr Serge Messier).

Risk Factors for SARS-CoV-2 Infection and Illness in Cats and Dogs1.

We tested swab specimens from pets in households in Ontario, Canada, with human COVID-19 cases by quantitative PCR for SARS-CoV-2 and surveyed pet owners for risk factors associated with infection and seropositivity. We tested serum samples for spike protein IgG and IgM in household pets and also in animals from shelters and low-cost neuter clinics. Among household pets, 2% (1/49) of swab specimens from dogs and 7.7% (5/65) from cats were PCR positive, but 41% of dog serum samples and 52% of cat serum samples were positive for SARS-CoV-2 IgG or IgM. The likelihood of SARS-CoV-2 seropositivity in pet samples was higher for cats but not dogs that slept on owners' beds and for dogs and cats that contracted a new illness. Seropositivity in neuter-clinic samples was 16% (35/221); in shelter samples, 9.3% (7/75). Our findings indicate a high likelihood for pets in households of humans with COVID-19 to seroconvert and become ill.

Effect of up to 30-days of storage at different temperatures on detection of feline kidney injury molecule-1 in urine.

BACKGROUND: In humans, kidney injury molecule-1 (KIM-1) is a biomarker of acute kidney injury that can be quantified in urine. Preliminary investigation in cats with experimentally induced acute kidney injury showed that KIM-1 urine concentration correlated with kidney injury histopathology scores. A lateral flow assay (LFA) has recently become available for patient-side feline KIM-1 measurement. In vitro parameters of the assay have not yet been determined. The objectives of this study were to determine detection of KIM-1 in urine stored at different temperatures over time, to establish the linear range of the LFA, and to assess the intra-assay repeatability of measurements.  RESULTS: Ten urine samples with a range of KIM-1 concentrations were stored at room temperature (22o C), 4o C or -20o C, and tested with the LFA on days 0, 1, 2, 3, 7, 14, and 30. The concentration of KIM-1 in samples was not significantly different from the day 0 value, except one sample that had been stored for 30 days at room temperature yielded a significantly higher value. The assay results had a correlation coefficient of 0.922. The mean coefficient of variation for all samples was 15.7%. The slope of the curve of expected versus measured values in samples diluted two-fold nine times was 0.908, and results were linear over all dilutions. CONCLUSIONS: The LFA for feline KIM-1 yields consistent results from stored urine samples. These characteristics will allow for KIM-1 to be measured retrospectively if immediate testing is not feasible. Within assay precision was high, and linearity over 9 logs of dilution suggests suitability for a range of subclinical and clinical kidney injuries.

Bronchial brush cytology, endobronchial biopsy, and SALSA immunohistochemistry in severe equine asthma.

Horses with severe equine asthma (SEA), also known as heaves and recurrent airway obstruction, have persistent neutrophilic inflammation of the lower airways. Cytologic evaluation of bronchoalveolar lavage (BAL) fluid is commonly used to confirm the clinical diagnosis of SEA. However, the utility of microscopic assessment of bronchial brushings, endobronchial biopsies, and immunohistochemical detection of disease-associated biomarkers for the diagnosis of SEA remain poorly characterized. Salivary scavenger and agglutinin (SALSA) has anti-inflammatory properties and downregulated gene expression in SEA; therefore, it was investigated as a tissue biomarker for airway and systemic inflammation. Six asthmatic and 6 non-asthmatic horses were exposed to an inhaled challenge. Before and after challenge, samples of BAL fluid, bronchial brushing, and endobronchial biopsy were collected. Location of SALSA in biopsies was determined, and immunohistochemical label intensity was computed using image analysis software. Serum amyloid A (SAA) was measured to assess systemic inflammation. After challenge, neutrophil proportions were significantly higher in asthmatic versus non-asthmatic horses in BAL fluid (least squares means, 95% confidence interval: 80.9%, 57.2% to 93.1%, vs 3.6%, 1.1% to 10.7%) and in brush cytology slides (39.5%, 7.7% to 83.6%, vs 0.2%, 0% to 2.3%), illustrating the potential of brush cytology as an alternate modality to BAL for assessing intraluminal inflammation. Bronchial histopathologic findings and intensity of SALSA immunolabeling in surface and glandular epithelium were similar in asthmatic and non-asthmatic horses, indicating limited changes in bronchial tissue from the inhaled challenge. Increases in SAA indicated systemic inflammation, but SALSA immunolabeling did not change significantly.

Flow cytometric analysis of equine bronchoalveolar lavage fluid cells in horses with and without severe equine asthma.

Severe equine asthma (SEA) is a common, debilitating lower airway inflammatory disorder of older horses. Alveolar macrophages (AMs) survey inhaled particulates from barn sources causing them to switch from an anti-inflammatory to a proinflammatory phenotype, resulting in neutrophil recruitment to the lung. This proinflammatory switch may contribute to the development and prolongation of SEA. Validated antibodies to identify the cells involved in the pathogenesis of SEA are lacking. In this study, monoclonal antibodies against CD90, CD163, and CD206 were tested for reactivity with equine leukocytes by immunocytochemistry and flow cytometry. A multi-color flow cytometric assay was developed to identify leukocytes in equine bronchoalveolar lavage fluid (BALF). Four control and 4 SEA-susceptible horses had BALF collected before and after a 48-hour moldy hay challenge. Antibodies against CD90 uniquely labeled equine neutrophils, and antibodies against CD163 and CD206 identified equine macrophages. Postchallenge AM surface expression of CD163 increased in both groups of horses, but the increase was statistically significant in only the SEA-susceptible group (P = .02). The surface expression of CD206 on AMs increased significantly in the SEA-susceptible group (P = .03) but was unchanged in the control group (P = .5). Increased expression of CD163 and CD206 during exacerbation of SEA suggested an association between AM phenotype and lung inflammation. However, functions of AMs in the pathogenesis of SEA remain to be elucidated.

Use of immune repertoire sequencing to resolve discordant microscopic and immunochemical findings in a case of T cell-rich large B cell lymphoma in a young dog.

BACKGROUND: Lymphocytic neoplasms with frequent reactive lymphocytes are uncommonly reported in dogs, and can pose a diagnostic challenge. Different diagnostic modalities such as cytology, flow cytometry, histopathology, immunohistochemistry, and clonality testing, are sometimes required for a diagnosis. This report illustrates the value of using a multi-modal diagnostic approach to decipher a complex lymphocytic tumor, and introduces immune repertoire sequencing as a diagnostic adjunct. CASE PRESENTATION: A 10-month-old Great Dane was referred for marked ascites. Cytologic analysis of abdominal fluid and hepatic aspirates revealed a mixed lymphocyte population including numerous large lymphocytes, yielding a diagnosis of lymphoma. Flow cytometrically, abdominal fluid lymphocytes were highly positive for CD4, CD5, CD18, CD45, and MHC II, consistent with T cell lymphoma. Due to a rapidly deteriorating clinical condition, the dog was euthanized. Post mortem histologic evaluation showed effacement of the liver by aggregates of B cells surrounded by T cells, suggestive of hepatic T cell-rich large B cell lymphoma. Immune repertoire sequencing confirmed the presence of clonal B cells in the liver but not the abdominal fluid, whereas reactive T cells with shared, polyclonal immune repertoires were found in both locations. CONCLUSIONS: T cell-rich large B cell lymphoma is a rare neoplasm in dogs that may be challenging to diagnose and classify due to mixed lymphocyte populations. In this case, the results of histopathology, immunohistochemistry and immune repertoire sequencing were most consistent with a hepatic B cell neoplasm and reactive T cells exfoliating into the abdominal fluid. Immune repertoire sequencing was helpful in delineating neoplastic from reactive lymphocytes and characterizing repertoire overlap in both compartments. The potential pitfalls of equating atypical cytomorphology and monotypic marker expression in neoplasia are highlighted.

Bone Marrow Examination: Why, How, and What to Expect from the Pathologist.

This article describes the indications for sampling of bone marrow, the technical aspects of obtaining marrow core biopsies and aspirates, and the preparation of marrow smears. All aspects are illustrated with clinical cases. The information that can be expected from the pathologist's report of marrow samples is outlined, and the clinical features and prognosis of different types of leukemia are detailed.

Flow Cytometric Detection of Circulating Osteosarcoma Cells in Dogs.

Osteosarcoma (OSA) is a malignant tumor of middle-aged dogs and adolescent humans. The clinical outcome of OSA has not improved over more than three decades, and dogs typically succumb to metastatic disease within 6 months despite tumor resection through limb amputation and adjuvant chemotherapy. Therefore, undetectable tumor cells with potential to form metastases are present at diagnosis. An assay to identify canine immortalized and primary OSA cells through flow cytometric detection of intracellular collagen 1 (Col I) and osteocalcin was optimized, and applied to blood samples from tumor-bearing dogs for detection of circulating tumor cells (CTCs). Spiking variable number of OSA cells into normal dog blood recovered 50-60% of Col I positive cells with high forward and variable side light scatter. An algorithm to exclude nonviable, doublet, and autofluorescent cells was applied to sequential blood samples from three dogs obtained prior to and after limb amputation, and at approximately, triweekly intervals over 121, 142, and 183 days of chemotherapy, respectively. Dogs had >100 CTC/106 leukocytes prior to amputation, variably frequent CTC during chemotherapy, and an increase up to 4,000 CTC/106 leukocytes within 4 weeks before overt metastases or death. Sorted CTCs were morphologically similar to direct tumor aspirates and positive for Col I. Although preliminary, findings suggest that CTCs are frequent in canine OSA, more numerous than carcinoma CTC in humans, and that an increase in CTC frequency may herald clinical deterioration. This assay may enable enumeration and isolation of OSA CTC for prognostic and functional studies, respectively. © 2019 International Society for Advancement of Cytometry.

Composite lymphoma of concurrent T zone lymphoma and large cell B cell lymphoma in a dog.

BACKGROUND: Evolution of indolent to aggressive lymphoma has been described in dogs but is difficult to distinguish from the de novo development of a second, clonally distinct lymphoma. Differentiation of these scenarios can be aided by next generation sequencing (NGS)-based assessment of clonality of lymphocyte antigen receptor genes. CASE PRESENTATION: An 8-year-old male intact Mastiff presented with generalized lymphadenomegaly was diagnosed with nodal T zone lymphoma (TZL) based on cytology, histopathology, immunohistochemistry and flow cytometry. Thirteen months later, the dog re-presented with progressive lymphadenomegaly, and based on cytology and flow cytometry, a large B cell lymphoma (LBCL) was diagnosed. Sequencing-based clonality testing confirmed the de novo development of a LBCL and the persistence of a TZL. CONCLUSIONS: The occurrence of two distinct lymphoid neoplasms should be considered if patient features and tumor cytomorphology or immunophenotype differ among sequential samples. Sequencing-based clonality testing may provide conclusive evidence of two concurrent and distinct clonal lymphocyte populations, termed most appropriately "composite lymphoma".

RNA disruption indicates CHOP therapy efficacy in canine lymphoma.

BACKGROUND: Assessment of the efficacy of a multi-agent chemotherapy protocol in which cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) are administered in canine lymphoma is generally performed by physical measurement of lymph node diameter. However, no consistent correlation has been made with prognostic indicators and the length or absence of clinical remission based on lymph node size. RNA disruption measured mid-therapy has been correlated with increased disease-free survival in recent studies of human cancer and was assessed in this study of canine lymphoma patients. Fine needle aspirate samples were taken before treatment and at weeks 3, 6, and 11 of CHOP therapy. RNA was isolated from these samples and assessed using an Agilent Bioanalyzer. RNA disruption assay (RDA) analysis was performed on the data from the resulting electropherograms. RESULTS: An increased RNA disruption index (RDI) score was significantly associated with improved progression-free survival. CONCLUSIONS: Predicting the risk of early relapse during chemotherapy could benefit veterinary patients by reducing ineffective treatment and could allow veterinary oncologists to switch earlier to a more effective drug regimen.

Alveolar echinococcosis in an Ontario dog resembling an hepatic abscess.

A boxer dog was evaluated because of lethargy, vomiting, and abdominal pain. Ultrasonography revealed multiple cystic structures in the abdomen. Exploratory laparotomy revealed 3 well-encapsulated hepatic masses and abdominal effusion with suppurative inflammation. Collectively, these findings suggested the hepatic masses were most likely abscesses. However, histologic examination of the hepatic masses revealed multi-cystic structures, consistent with alveolar echinococcosis. The diagnosis was confirmed by DNA sequencing. The dog was treated with daily albendazole, but within a few weeks exhibited adverse side effects. After 6 months, the dog's condition deteriorated, and it was euthanized.

Échinococcose alvéolaire ressemblant à un abcès hépatique chez un chien en Ontario. Un chien de race boxer fut évalué à cause de léthargie, vomissements, et douleur abdominale. Une échographie révéla de multiples structures kystiques dans l'abdomen. Une laparotomie exploratoire révéla trois masses hépatiques bien encapsulées et une effusion abdominale avec inflammation suppurative. Collectivement, ces données suggéraient que les masses hépatiques étaient fort probablement des abcès. Toutefois, l'examen histologique des masses hépatiques révéla des structures multi-kystiques, compatibles avec une échinococcose alvéolaire. Le diagnostic fut confirmé par séquençage d'ADN. Le chien fut traité avec de l'albendazole quotidiennement, mais en quelques semaines il montra des signes d'effets adverses. Après 6 mois la condition du chien se détériora et il fut euthanasié.(Traduit par Dr Serge Messier).

Acute Leukemia in Horses.

Leukemia is broadly divided into acute and chronic lymphocytic and myeloid types based on the proportion of blasts, morphology of cells, and expression of specific antigens on neoplastic cells. Classifying leukemia in horses can be challenging if blasts predominate and since few antibodies to identify cell types are available. The objective of this study was to describe in detail the clinical and pathologic features of acute leukemia in horses. Twelve horses ranging from 0.2 to 25.9 years of age were diagnosed with acute leukemia. Six cases were classified as acute lymphocytic leukemia (ALL) based on predominance of blasts, lack of granulocytic or monocytic differentiation, and detection of CD3, CD20, and/or CD79a antigens by immunohistochemistry. Six other cases were classified as acute myeloid leukemia (AML) with myelomonocytic ( n = 4), basophilic ( n = 1), and eosinophilic ( n = 1) differentiation based on > 20% bone marrow blasts and partial leukocytic differentiation. Reactivity with antibodies to Iba-1/AIF-1, CD172a, and CD163 was determined for all cases of AML. Eleven horses had thrombocytopenia, 10 had neutropenia, 8 had anemia, all had blasts on blood films, and none had leukocytosis. Ten horses had increased serum acute phase proteins. Bone marrow cellularity ranged from 30% to 100%, and the proportion of blasts ranged from 80% to 100% and 30% to 60% in ALL and AML, respectively. Horses were severely ill at diagnosis and euthanized within days or weeks. Unique features of acute leukemia in horses compared to other species were variable lymphocyte antigen expression (ALL) and frequent inflammation (ALL and AML).

Short communication: The effect of calcium supplementation at calving on neutrophil function.

Low total blood calcium concentration after calving has been demonstrated to be a risk factor for reduced neutrophil function. The objective of this study was to evaluate whether administration of an injectable calcium supplement product soon after calving increased neutrophil oxidative burst or phagocytosis capacity. Cows (n = 27) from 4 farms were blocked by parity and randomly assigned to receive either calcium gluconate (35% wt/vol) in combination with calcium glucoheptonate (10% wt/vol; Theracalcium, Vétoquinol Canada Inc., Lavaltrie, Quebec, Canada) or a placebo within 12 h after calving and again 24 h later. Each dose of 120 mL was injected subcutaneously over 2 sites. Total serum calcium concentration, neutrophil oxidative burst, and neutrophil phagocytosis capacity were measured from coccygeal blood samples before (time 0) and 72 h after first treatment. There was no difference between treatment groups in lactation number, total calcium concentration, oxidative burst, or phagocytosis at time of enrollment. There was no effect of treatment on oxidative burst or phagocytosis by neutrophils. This preliminary study does not support an effect of supplemental calcium to improve neutrophil oxidative burst or phagocytosis capacity of low-parity parturient cows.

The effect of prepartum feeding and lying space on metabolic health and immune function.

The determinants of metabolic and reproductive health disorders in the peripartum period and the degree to which feeding and lying space and management can influence health are only partially understood. The objective of this randomized controlled study was to determine whether providing noncompetitive feeding and lying access in the close-up dry period improves health and immune function. Forty-eight Holstein cows of all parities were randomly assigned to a treatment group of 6 to 10 cows in 1 pen with either 80% cows to stalls and 90 cm of feeding space per cow (understocked) or 120% stocking density and 45 cm of feeding space per cow (overstocked) for 3 wk before expected calving. All cows wore electronic data loggers to monitor daily standing and lying time. Video recordings representing d 7 to 9 after group formation were reviewed, and a competition index (C_Ind) was calculated for each cow by dividing the number of times a cow displaced another as an actor by its total number of actor and reactor displacements. Cows were categorized as high success (C_Ind ≥0.6), moderate success (0.4 ≤ C_Ind <0.6), or low success (C_Ind <0.4). Weekly blood samples measured nonesterified fatty acids, ß-hydroxybutyrate, calcium, glucose, albumin, aspartate aminotransferase, bilirubin, haptoglobin, insulin, and insulin-like growth factor-1 from 3 wk before to 5 wk after calving. Measures of innate immune function (neutrophil phagocytosis and oxidative burst) were assessed at -2, -1, 1, 2, 3, and 5 wk relative to calving. Liver biopsies were collected at wk 1 and 3. Cows in the understocked group spent significantly more time per day lying; the back-transformed least squares means and 95% confidence interval were 14.8 h (13.9-15.6) versus 12.8 h (12.0-13.7). Controlling for parity, there was no difference between treatments in ß-hydroxybutyrate, nonesterified fatty acids, glucose, insulin, insulin-like growth factor 1, aspartate aminotransferase, bilirubin, or haptoglobin concentrations. Throughout the study, cows in the understocked treatment had higher mean calcium and tended to have higher albumin and at 3 wk after calving tended to have lower mean liver triacylglycerol content. Overall, there was no treatment effect on phagocytosis, but cows with a higher C_Ind in the understocked treatment group had greater oxidative burst function. There was no effect of treatment on endometritis. Despite increased competition and lower lying time, the expected harmful effects of crowding and competition on metabolic indicators and innate immune function were mostly not observed. Although this does not refute the importance of access to feeding and lying space, these results indicate that metabolic and reproductive health is more complex than can be explained solely by exposure to what are understood to be best practices for space allowances.

Impaired response of the bronchial epithelium to inflammation characterizes severe equine asthma.

BACKGROUND: Severe equine asthma is a naturally occurring lung inflammatory disease of mature animals characterized by neutrophilic inflammation, bronchoconstriction, mucus hypersecretion and airway remodeling. Exacerbations are triggered by inhalation of dust and microbial components. Affected animals eventually are unable of aerobic performance. In this study transcriptomic differences between asthmatic and non-asthmatic animals in the response of the bronchial epithelium to an inhaled challenge were determined. RESULTS: Paired endobronchial biopsies were obtained pre- and post-challenge from asthmatic and non-asthmatic animals. The transcriptome, determined by RNA-seq and analyzed with edgeR, contained 111 genes differentially expressed (DE) after challenge between horses with and without asthma, and 81 of these were upregulated. Genes involved in neutrophil migration and activation were in central location in interaction networks, and related gene ontology terms were significantly overrepresented. Relative abundance of specific gene products as determined by immunohistochemistry was correlated with differential gene expression. Gene sets involved in neutrophil chemotaxis, immune and inflammatory response, secretion, blood coagulation and apoptosis were overrepresented among up-regulated genes, while the rhythmic process gene set was overrepresented among down-regulated genes. MMP1, IL8, TLR4 and MMP9 appeared to be the most important proteins in connecting the STRING protein network of DE genes. CONCLUSIONS: Several differentially expressed genes and networks in horses with asthma also contribute to human asthma, highlighting similarities between severe human adult and equine asthma. Neutrophil activation by the bronchial epithelium is suggested as the trigger of the inflammatory cascade in equine asthma, followed by epithelial injury and impaired repair and differentiation. Circadian rhythm dysregulation and the sonic Hedgehog pathway were identified as potential novel contributory factors in equine asthma.

Genome-wide assessment of recurrent genomic imbalances in canine leukemia identifies evolutionarily conserved regions for subtype differentiation.

Leukemia in dogs is a heterogeneous disease with survival ranging from days to years, depending on the subtype. Strides have been made in both human and canine leukemia to improve classification and understanding of pathogenesis through immunophenotyping, yet classification and choosing appropriate therapy remains challenging. In this study, we assessed 123 cases of canine leukemia (28 ALLs, 24 AMLs, 25 B-CLLs, and 46 T-CLLs) using high-resolution oligonucleotide array comparative genomic hybridization (oaCGH) to detect DNA copy number alterations (CNAs). For the first time, such data were used to identify recurrent CNAs and inclusive genes that may be potential drivers of subtype-specific pathogenesis. We performed predictive modeling to identify CNAs that could reliably differentiate acute subtypes (ALL vs. AML) and chronic subtypes (B-CLL vs. T-CLL) and used this model to differentiate cases with up to 83.3 and 95.8 % precision, respectively, based on CNAs at only one to three genomic regions. In addition, CGH datasets for canine and human leukemia were compared to reveal evolutionarily conserved copy number changes between species, including the shared gain of HSA 21q in ALL and ∼25 Mb of shared gain of HSA 12 and loss of HSA 13q14 in CLL. These findings support the use of canine leukemia as a relevant in vivo model for human leukemia and justify the need to further explore the conserved genomic regions of interest for their clinical impact.