Hematologic and Serum Biochemical Characteristics of Belgian Blue Cattle.

Belgian blue (BB) cattle have an 11-bp deletion in myostatin that causes skeletal muscle hyperplasia and increased muscle mass, leading to a 'double-muscled' phenotype. Preliminary data suggest that this phenotype may be associated with breed-specific hematologic and biochemical values. Therefore, in this study, we sought to compare hematologic and serum biochemical parameters in healthy BB and Holstein Friesian (HF) cows and to propose breed-specific reference intervals for BB cows. Hematologic parameters, total protein, creatinine, creatine kinase (CK) and aspartate transaminase (AST) activities, albumin, and globulins were measured in 183 clinically healthy adult BB and HF cows. There were significant differences between BB and HF cows in 17 of 27 measured parameters. BB cows had significantly higher creatinine concentration and CK and AST activities (p < 0.001). RBCs, hemoglobin, hematocrit (p < 0.001), MCV and lymphocytes (p < 0.05) were also significantly higher in BB cows compared with HF cows. The average N/L ratio was greater than 1 in both breeds. These results suggest that BB and HF cows have significantly different clinically relevant hematologic and serum biochemical values, and, therefore, breed-specific reference intervals should be used.

Reduce, Replace, Refine: Determining A Posteriori Reference Intervals for Biochemistry in Hermann's Tortoise (Testudo hermanni).

Biochemical and hematological analyses are important for the assessment of animal health. However, for most wild species their use is hindered by the scarcity of reliable reference intervals. Indeed, collecting body fluids (e.g., blood, urine) in free-ranging animals is often technically challenging. Further, sampling many individuals would be essential to consider major sources of variations, such as species, populations, sex, age, and seasons. One alternative, according to the reduction, refinement, and replacement framework, is to establish reference intervals a posteriori using literature survey and unpublished data. We produced reference intervals for free-ranging Hermann's tortoises (Testudo hermanni), using analyses performed on blood samples collected in previous studies and conservation programs conducted in the field between 2010 and 2016 in southern France (n=195 individuals). Thirteen parameters were analyzed: packed-cell volume, blood concentrations of corticosterone, testosterone, glycemia, cholesterol, triglyceride, urea, uric acid, calcium, sodium, potassium, asparagine aminotransferase (AST), and alanine aminotransferases (ALT). Reference intervals for subgroups defined by sex and season were relevant for corticosterone, triglyceride, and calcium (sex) and cholesterol (season). Comparing our results with those obtained in captive individuals in Germany, except for urea and AST levels the intervals from both free-ranging versus captive tortoises were similar, suggesting that reference intervals established from captive individuals may be suitable for free-ranging populations in this species.

Incidentally detected retroperitoneal paraganglioma in a 10-year-old French bulldog.

This article reports a case of a 10-year-old French bulldog initially seen for reluctance to move and episodes of pain. A magnetic resonance imaging study was undertaken in order to rule out a herniated disc. A large, retroperitoneal mass was visualized and cytological analysis suggested a neoplastic proliferation. The mass appeared to compress the caudal vena cava when viewed by abdominal CT scan. The mass was surgically removed. A nephrectomy was also carried out and aortic bleeding identified after dissection of adhesions. Despite these complications, the dog did well after the procedures. Postoperative checkups were normal. Histological and immunohistochemical analyses of the mass were compatible with a retroperitoneal paraganglioma. Key clinical message: This type of tumor is poorly described in the veterinary literature. As the behavior of this tumor type is not yet fully understood, each new description adds to our knowledge and should help in diagnosing and treating it more effectively in the future.

Paragangliome rétropéritonéal de découverte fortuite chez un bouledogue Français de 10 ans. Cet article expose le cas d'un chien mâle entier bouledogue Français de 10 ans présenté initialement pour des difficultés locomotrices et des manifestations algiques. Un examen d'imagerie par résonnance magnétique (IRM) est rapidement réalisé afin d'explorer l'hypothèse d'une hernie discale. Une volumineuse masse rétropéritonéale est alors mise en évidence. L'analyse cytologique de cette dernière est compatible avec un processus néoplasique. Après la réalisation d'un examen par tomodensitométrie de l'abdomen et la mise en évidence d'une compression marquée de la veine cave caudale par la masse, une prise en charge chirurgicale avec exérèse de la masse est décidée. Lors de l'intervention chirurgicale une néphrectomie est réalisée et un saignement aortique est identifié après la dissection des adhérences. Malgré ces complications, le chien se réveille bien et les contrôles post opératoires effectués sont satisfaisants. Les analyses histologiques et immunohistochimiques de la masse seront en faveur d'un paragangliome rétropéritonéal extra surrénalien.Message clinique clé :Ce type tumoral fait l'objet de peu de descriptions dans la littérature vétérinaire. Toute la lumière n'a pas encore été faite sur son comportement et chaque nouvelle description permet d'en enrichir les connaissances et donc de mieux comprendre ce type tumoral, ce qui, à l'avenir, pourra aider à le diagnostiquer plus facilement et à le traiter plus efficacement.(Traduit par les auteurs).

Bronchoalveolar Lavage Fluid Cytology in Healthy Cynomolgus Macaques.

Bronchoalveolar lavage, or BAL, is a minimally invasive procedure frequently used for clinical and non-clinical research, allowing studies of the respiratory system. Macaques are the most widely used non-human primate models in biomedical research. However, very little information is available in the literature concerning BAL cytology in macaques. The purpose of this study was to establish BAL reference values and document an atlas of BAL cytology from healthy cynomolgus macaques. BALs were obtained from 30 macaques and BAL fluid differential cell counts based on 400 nucleated cells/BAL sample were performed by a board-certified clinical pathologist. Results were analyzed using Reference Value Advisor macroinstructions and the effect of blood and oropharyngeal contaminations was investigated. Overall, nucleated cells interval percentages in BAL fluids were 55.8 to 93.7 for macrophages, 1.8 to 37.1 for lymphocytes, 0.4 to 8.7 for neutrophils, and 0.4 to 9.8 for eosinophils. Mild oropharyngeal contamination did not affect BAL differential cell counts, whilst a slight but significant increase of the percentage of lymphocytes was observed in samples with mild blood contamination. Mucus and variable numbers of ciliated epithelial cells were commonly present. Rarely, multinucleated macrophages and mastocytes were also observed. The reference intervals established in this study provide a useful baseline for the assessment of BAL cytological data in cynomolgus macaques.

Loss of tRNA-modifying enzyme Elp3 activates a p53-dependent antitumor checkpoint in hematopoiesis.

The hematopoietic system is highly sensitive to perturbations in the translational machinery, of which an emerging level of regulation lies in the epitranscriptomic modification of transfer RNAs (tRNAs). Here, we interrogate the role of tRNA anticodon modifications in hematopoiesis by using mouse models of conditional inactivation of Elp3, the catalytic subunit of Elongator that modifies wobble uridine in specific tRNAs. Loss of Elp3 causes bone marrow failure by inducing death in committing progenitors and compromises the grafting activity of hematopoietic stem cells. Mechanistically, Elp3 deficiency activates a p53-dependent checkpoint in what resembles a misguided amino acid deprivation response that is accompanied by Atf4 overactivation and increased protein synthesis. While deletion of p53 rescues hematopoiesis, loss of Elp3 prompts the development of p53-mutated leukemia/lymphoma, and inactivation of p53 and Elongator cooperatively promotes tumorigenesis. Specific tRNA-modifying enzymes thus condition differentiation and antitumor fate decisions in hematopoietic stem cells and progenitors.

Lung-resident eosinophils represent a distinct regulatory eosinophil subset.

Increases in eosinophil numbers are associated with infection and allergic diseases, including asthma, but there is also evidence that eosinophils contribute to homeostatic immune processes. In mice, the normal lung contains resident eosinophils (rEos), but their function has not been characterized. Here, we have reported that steady-state pulmonary rEos are IL-5-independent parenchymal Siglec-FintCD62L+CD101lo cells with a ring-shaped nucleus. During house dust mite-induced airway allergy, rEos features remained unchanged, and rEos were accompanied by recruited inflammatory eosinophils (iEos), which were defined as IL-5-dependent peribronchial Siglec-FhiCD62L-CD101hi cells with a segmented nucleus. Gene expression analyses revealed a more regulatory profile for rEos than for iEos, and correspondingly, mice lacking lung rEos showed an increase in Th2 cell responses to inhaled allergens. Such elevation of Th2 responses was linked to the ability of rEos, but not iEos, to inhibit the maturation, and therefore the pro-Th2 function, of allergen-loaded DCs. Finally, we determined that the parenchymal rEos found in nonasthmatic human lungs (Siglec-8+CD62L+IL-3Rlo cells) were phenotypically distinct from the iEos isolated from the sputa of eosinophilic asthmatic patients (Siglec-8+CD62LloIL-3Rhi cells), suggesting that our findings in mice are relevant to humans. In conclusion, our data define lung rEos as a distinct eosinophil subset with key homeostatic functions.

Expression microarray as a tool to identify differentially expressed genes in horses suffering from inflammatory airway disease.

BACKGROUND: Inflammatory airway disease (IAD) affects performance and well-being of horses. Diagnosis is primarily reached by bronchoalveolar lavage (BAL) cytology which is invasive and requires sedation. OBJECTIVES: The purpose of this study was to identify differential gene expression in peripheral blood of horses with IAD using species-specific expression microarrays. METHODS: Equine gene expression microarrays were used to investigate global mRNA expression in circulating leukocytes from healthy, IAD-affected, and low-performing Standardbred and endurance horses. RESULTS: Nine genes in Standardbred and 61 genes in endurance horses were significantly differentially regulated (P < .001). These genes were related to inflammation (eg, ALOX15B, PLA2G12B, and PENK), oxidant/antioxidant balance (eg, DUOXA2 and GSTO1-1), and stress (eg, V1aR, GRLF1, Homer-2, and MAOB). All these genes were up-regulated, except down-regulated Homer-2 and MAOB. DUOXA2, ALOX15B, PLA2G12B, MAOB, and GRLF1 expression was further validated by RT-qPCR. An increase in glutathione peroxidase (GPx) activity in heparinized whole blood of IAD-affected Standardbred (P = .0025) and endurance horses (P = .0028) also suggests a deregulation of the oxidant/antioxidant balance. There was good correlation (r = .7354) between BAL neutrophil percentage and whole blood GPx activity in all horses. CONCLUSIONS: This study showed that circulating blood cell gene expression reflects inflammatory responses in tissues. Whether any of the genes have potential for diagnostic applications in the future remains to be investigated. Although not specific for IAD, whole blood GPx activity appears to be correlated with BAL neutrophil percentage. This finding should be further assessed by testing a larger number of horses.

Rasa3 controls megakaryocyte Rap1 activation, integrin signaling and differentiation into proplatelet.

Rasa3 is a GTPase activating protein of the GAP1 family which targets Ras and Rap1. Ubiquitous Rasa3 catalytic inactivation in mouse results in early embryonic lethality. Here, we show that Rasa3 catalytic inactivation in mouse hematopoietic cells results in a lethal syndrome characterized by severe defects during megakaryopoiesis, thrombocytopenia and a predisposition to develop preleukemia. The main objective of this study was to define the cellular and the molecular mechanisms of terminal megakaryopoiesis alterations. We found that Rasa3 catalytic inactivation altered megakaryocyte development, adherence, migration, actin cytoskeleton organization and differentiation into proplatelet forming megakaryocytes. These megakaryocyte alterations were associated with an increased active Rap1 level and a constitutive integrin activation. Thus, these mice presented a severe thrombocytopenia, bleeding and anemia associated with an increased percentage of megakaryocytes in the bone marrow, bone marrow fibrosis, extramedular hematopoiesis, splenomegaly and premature death. Altogether, our results indicate that Rasa3 catalytic activity controls Rap1 activation and integrin signaling during megakaryocyte differentiation in mouse.

Evaluation of the cytotoxicity of organic dust components on THP1 monocytes-derived macrophages using high content analysis.

Organic dust contains pathogen-associated molecular patterns (PAMPs) which can induce significant airway diseases following chronic exposure. Mononuclear phagocytes are key protecting cells of the respiratory tract. Several studies have investigated the effects of PAMPs and mainly endotoxins, on cytokine production. However the sublethal cytotoxicity of organic dust components on macrophages has not been tested yet. The novel technology of high content analysis (HCA) is already used to assess subclinical drug-induced toxicity. It combines the capabilities of flow cytometry, intracellular fluorescence probes, and image analysis and enables rapid multiple analyses in large numbers of samples. In this study, HCA was used to investigate the cytotoxicity of the three major PAMPs contained in organic dust, i.e., endotoxin (LPS), peptidoglycan (PGN) and ß-glucans (zymosan) on THP-1 monocyte-derived macrophages. LPS was used at concentrations of 0.005, 0.01, 0.02, 0.05, 0.1, and 1 µg/mL; PGN and zymosan were used at concentrations of 1, 5, 10, 50, 100, and 500 µg/mL. Cells were exposed to PAMPs for 24 h. In addition, the oxidative burst and the phagocytic capabilities of the cells were tested. An overlap between PGN intrinsic fluorescence and red/far-red fluorescent dyes occurred, rendering the evaluation of some parameters impossible for PGN. LPS induced sublethal cytotoxicity at the lowest dose (from 50 ng/mL). However, the greatest cytotoxic changes occurred with zymosan. In addition, zymosan, but not LPS, induced phagosome maturation and oxidative burst. Given the fact that ß-glucans can be up to 100-fold more concentrated in organic dust than LPS, these results suggest that ß-glucans could play a major role in macrophage impairment following heavy dust exposure and will merit further investigation in the near future.

Bacterial cholangiohepatitis in a dog.

A 9-year-old female Yorkshire terrier was presented for vomiting and diarrhea. Blood chemistry tests revealed hepatic dysfunction, cholestasis, and inflammation. Liver ultrasonography and liver biopsy were consistent with cholangiohepatitis. Fine-needle aspiration of the gallbladder revealed the presence of bacteria later identified as Clostridium spp. The cholangiohepatitis was successfully treated.

Assessing fitness in endurance horses.

A field test and a standardized treadmill test were used to assess fitness in endurance horses. These tests discriminated horses of different race levels: horses participating in races of 120 km and more showed higher values of VLA4 (velocity at which blood lactate reached 4 mmol/L) and V200 (velocity at which heart rates reached 200 beats per min) than horses of lower race levels.

Emergence of bovine ehrlichiosis in Belgian cattle herds.

Bovine ehrlichiosis is a tick-borne rickettsial disease caused by Anaplasma phagocytophilum. The disease can also be transmitted to humans. Outbreaks in cattle have been described in many European countries. In Belgium, infections caused by A. phagocytophilum have been reported in humans and dogs; however, this paper details the first report of ehrlichiosis in cattle herds in Belgium. The first case described was in a dairy herd located in eastern Belgium. Clinical signs included hyperthermia, polypnea, and swelling of the limbs. The other case was diagnosed in a second, mixed purpose herd in western Belgium. Within the second herd, all of the affected animals came from the same pasture. All animals in that pasture showed recurrent hyperthermia, and some also showed signs of mastitis and late-term abortions. Blood smears and serology revealed the presence of A. phagocytophilum in the majority of animals with pyrexia. Furthermore, the presence of leptospirosis, Neospora caninum, and Q fever antibodies was tested by serological analysis, but all results were negative. Paired serology for Adenovirus, BHV-4, BHV-1, BVD, PI3, and RSV-B did not show any significant seroconversion. Milk samples from cows affected by mastitis revealed minor pathogens. Fecal testing for the presence of Dictyocaulus viviparus in the first herd was negative. Recurrent pyrexia in pastured cattle is a non-specific sign, and can be related to several different pathogens. Bovine ehrlichiosis is transmitted by the tick species Ixodes ricinus which is known to be present throughout Belgium. Belgian practitioners should include ehrlichiosis in their differential diagnosis when confronted with pastured cattle suffering from recurrent pyrexia.

Effect of a combined iodine and selenium supplementation on I and Se status of cows and their calves.

Iodine (I) and selenium (Se) deficiencies are commonly reported in cattle, however, there are also studies regarding a very high iodine supply. The aim of the study was to determine the long-term effect of I and Se supplementation on non-pregnant cows, pregnant cows and their calves. The hypothalamus pituitary axis was investigated (TSH, T4, T3 assays) during a TRH challenge on non-pregnant cows. Twenty-four cows, half of them pregnant, were assigned into 2 diet-groups, one group with a low I (0.45 ppm) and Se (0.15 ppm) diet (LISe), the other with a high I (5.45 ppm) and Se (0.45 ppm) diet (HISe), for a period of 120 days. Nutritional (plasma iodide, urinary I, plasma Se, I content in colostrum and foetal fluids) and functional (thyrotropin, thyroid hormones, glutathione-peroxidase activity in erythrocytes) markers of I and Se status were assayed in dams at regular intervals for 120 days and in their calves at birth. A TRH challenge was performed on 8 non-pregnant cows at day 110 of the trial. At the end of the study, I and Se nutritional markers were higher in dams in the HISe group, compared to the LISe group, except for plasma Se. At birth, I nutritional markers in calves in the HISe group were higher compared to the LISe group. Reactivity of the pituitary-thyroid-axis was not influenced by I and Se supplementation. I and Se supplementation is efficient in improving newborn status.

Characterization of pentraxin 3 in the horse and its expression in airways.

The long pentraxin 3 (PTX3) plays an important role in host defence and its over-expression may contribute to airway injury. The aim of the present study was therefore to characterize in more detail PTX3 and its expression in the horses' airway. Six healthy horses and six horses affected by recurrent airway obstruction (R.A.O.) were submitted to a dusty environment challenge. PTX3 DNA and cDNA were cloned and sequenced. PTX3 expression was evaluated by RT-qPCR, Western blotting and immunohistochemistry in bronchoalveolar lavage fluid (BALF) cells, BALF supernatant and bronchial epithelial cells. An alternative splicing of the second exon of PTX3 occurred, resulting in two forms of the protein: "spliced" (32 kDa) and "full length" (42 kDa). PTX3 was detected in BALF macrophages, neutrophils and bronchial epithelial cells. It was over-expressed in the BALF supernatant from R.A.O.-affected horses in crisis. However, dust was unable to induce PTX3 in BALF cells ex vivo, indicating that dust is an indirect inducer of PTX3. Dust exposure in-vivo induced PTX3 in BALF macrophages but there was no significant difference between healthy and R.A.O.-affected horses. Conversely, PTX3 was over-expressed in the bronchial epithelial cells from R.A.O.-affected horses in crisis. These data indicate a differential regulatory mechanism in inflammatory and bronchial epithelial cells and offer therapeutically interesting perspectives.

Expression microarrays in equine sciences.

Microarrays have become an important research tool for life science researchers. Expression microarrays are capable of profiling the gene expression pattern of tens of thousands of genes in a single experiment. It appears to be the platform of choice for parallel gene expression profiling. Various equine-specific gene expression microarrays have been generated and used. However, homologous microarrays are not yet commercially available for the horse. An alternative is the use of heterologous microarrays, mainly microarrays specific for mice or humans. Although the use of microarrays in equine research is still in its infancy, gene expression microarrays have shown their potential in equine research. This review presents the previous, current and potential use of expression microarrays in equine research.

Relevance of using a human microarray to study gene expression in heaves-affected horses.

Environmental causes of heaves are well described, but the molecular mechanisms of the disease remain unclear. Previous studies have highlighted the implications of variations in gene expression, most using reverse transcription polymerase chain reaction (RT-PCR). This well-known technique limits the number of genes that can be studied in a single assay. Microarray appears to be a valuable tool to by-pass this limitation, but so far there has been no equine-specific microarray available on the market. The present study was performed to determine whether a human microarray could be used to study gene expression in nucleated cells originating from peripheral blood and bronchoalveolar lavage fluid (BALF) in heaves-affected horses. With a four-fold cut-off, a total of 46 candidates were identified with differentially regulated genes between heaves-affected horses and controls. A real-time quantitative RT-PCR (RT-QPCR) conducted on a selection of genes, determined on the basis of previous publications, was used to validate the microarray results. The microarray failed to detect the presence of interleukin (IL)-1beta and IL-8 mRNA in the nucleated cells from BALF otherwise confirmed by real-time RT-QPCR. Although some candidate genes have been identified using this method, a complete expression profile of genes related to heaves could not be obtained with the use of the human microarray.