Microbiological Findings and Associated Histopathological Lesions in Neonatal Diarrhoea Cases between 2020 and 2022 in a French Veterinary Pig Practice.

This retrospective study described the aetiologies of neonatal diarrhoea cases and their associations with histological findings. A total of 106 diarrhoeic neonatal piglets were selected. Cultures, MALDI typings, PCRs and evaluation of intestinal lesions were performed. A total of 51 cases (48.1%) were positive for only one pathogen and 54 (50.9%) were positive for more than one pathogen. Clostridium perfringens type A was the most frequently detected pathogen (61.3%), followed by Enterococcus hirae (43.4%), rotavirus type A (38.7%), rotavirus type C (11.3%) and enterotoxigenic Escherichia coli (3.8%). Only lesions in the small intestine were correlated with detected pathogens. The detection of rotavirus was associated with an increased probability of observing villous atrophy (p < 0.001), crypt hyperplasia (p = 0.01) and leucocyte necrosis in the lamina propria (p = 0.05). The detection of Clostridium perfringens type A was associated with an increased probability of observing bacilli in close proximity to the mucosa (p < 0.001) and a decreased probability of observing epithelial necrosis (p = 0.04). Detection of Enterococcus hirae was associated with an increased probability of observing enteroadherent cocci (p < 0.001). Multivariate regression logistic models revealed that epithelial necrosis was more likely to occur in Enterococcus hirae-positive piglets (p < 0.02) and neutrophilic infiltrate was more likely to occur in Clostridium perfringens type A- and Enterococcus hirae-positive piglets (p = 0.04 and p = 0.02, respectively).

Toxic Effects of Fumonisins, Deoxynivalenol and Zearalenone Alone and in Combination in Ducks Fed the Maximum EUTolerated Level.

Toxic effects among fumonisins B (FB), deoxynivalenol (DON) and zearalenone (ZEN) administered alone and combined were investigated in 84-day-old ducks during force-feeding. 75 male ducks, divided into five groups of 15 animals, received daily during the meal a capsule containing the desired among of toxin. Treated animals received dietary levels of toxins equivalent to 20 mg FB1+FB2/kg (FB), 5 mg DON/kg (DON), 0.5 mg ZEN/kg (ZEN) and 20, 5 and 0.5 mg/kg of FB, DON and ZEN (FBDONZEN), respectively. Control birds received capsules with no toxin. After 12 days, a decrease in body weight gain accompanied by an increase in the feed conversion ratio was observed in ducks exposed to FBDONZEN, whereas there was no effect on performances in ducks exposed to FB, DON and ZEN separately. No difference among groups was observed in relative organ weight, biochemistry, histopathology and several variables used to measure oxidative damage and testicular function. A sphinganine to sphingosine ratio of 0.32, 1.19 and 1.04, was measured in liver in controls and in ducks exposed to FB and FBDONZEN, respectively. Concentrations of FB1 in liver were 13.34 and 15.4 ng/g in ducks exposed to FB and FBDONZEN, respectively. Together ZEN and its metabolites were measured after enzymatic hydrolysis of the conjugated forms. Mean concentrations of α-zearalenol in liver were 0.82 and 0.54 ng/g in ducks exposed to ZEN and FBDONZEN, respectively. ß-zearalenol was 2.3-fold less abundant than α-zearalenol, whereas ZEN was only found in trace amounts. In conclusion, this study suggests that decreased performance may occur in ducks exposed to a combination of FB, DON and ZEN, but does not reveal any other interaction between mycotoxins in any of the other variables measured.

Toxicity of Fumonisins, Deoxynivalenol, and Zearalenone Alone and in Combination in Turkeys Fed with the Maximum European Union-Tolerated Level.

Surveys of mycotoxins worldwide have shown that deoxynivalenol (DON), fumonisins (FB), and zearalenone (ZON) are the most abundant Fusarium mycotoxins (FUS) in European poultry feed, in both the level and the frequency of contamination. Previous studies reported that a combination of FUS at concentrations that individually are not toxic may negatively affect animals. However, although toxic thresholds and regulatory guidelines exist for FUS, none account for the risk of multiple contamination, which is the most frequent. The aim of this study was to compare DON, FB, and ZON toxicity, alone and in combination, in male turkey poults. Ground cultured toxigenic Fusarium strains were incorporated in corn-soybean-based feed in five experimental diets: control diet, containing no mycotoxins, DON diet (5 mg DON/kg), FB diet (20 mg FB1 + FB2/ kg), ZON diet (0.5 mg ZON/kg), and DONFBZON diet (5, 20, and 0.5 mg/kg of DON, FB1 + FB2, and ZON, respectively). Seventy male Grade Maker turkeys were reared in individual cages on mycotoxin-free diets from 0 to 55 days of age. On the 55th day, the turkeys were weighed and divided into five groups each comprising 14 birds. Each group was fed one of the five experimental diets for a period of 14 days. On the 70th day of age, feed was withheld for 8 hr, at which time a blood sample was collected, and then all the turkeys were killed, autopsied, and different tissues sampled. The weight of the different organs, analyses of performance, biochemistry, histopathology, oxidative damage, and testis toxicity revealed no significant effects attributable to FUS. Measurement of sphingolipids in the liver revealed an increase in the sphinganine to sphingosine ratio in turkeys fed diets containing FB, but had no apparent consequences in terms of toxicity. Finally, only slight differences were found in some variables and the results of this study showed no interactions between DON, FB, and ZON. Taken together, results thus suggest that the maximum tolerated levels established for individual contamination by DON, FB, and ZON can also be considered safe in turkeys fed with combinations of these FUS for a period of 14 days.

Toxicidad de fumonisinas, deoxinivalenol y zearalenona solos y en combinación en pavos alimentados con el nivel máximo tolerado por la Unión Europea. Investigaciones sobre micotoxinas en todo el mundo han demostrado que el deoxinivalenol (DON), las fumonisinas (FB) y la zearalenona (ZON) son las micotoxinas de Fusarium (FUS) más abundantes en la alimentación avícola europea, tanto en el nivel como en la frecuencia de la contaminación. Estudios anteriores informaron que una combinación de micotoxinas de Fusarium a concentraciones que individualmente no son tóxicas puede afectar negativamente a los animales. Sin embargo, aunque existen umbrales tóxicos y pautas regulatorias para las micotoxinas de Fusarium, ninguno tiene en cuenta el riesgo de contaminación múltiple, que es lo más frecuente. El objetivo de este estudio fue comparar la toxicidad deoxinivalenol, fumonisinas, y zearalenona, solas o en combinación en pavos machos. Cepas toxigénicas de Fusarium cultivadas en suelos fueron incorporadas en alimentos a base de maíz y soya en cinco dietas experimentales: dieta de control, que no contiene micotoxinas, dieta DON (5 mg DON/kg), dieta FB (20 mg FB1+FB2/kg), dieta ZON (0.5 mg de ZON/kg) y dieta DONFBZON (5, 20 y 0.5 mg/kg de deoxinivalenol, fumonisinas 1 y 2 y zearalenona, respectivamente). Setenta pavos machos Grado Maker fueron criados en jaulas individuales con dietas libres de micotoxinas de 0 a 55 días de edad. En el día 55, los pavos se pesaron y se distribuyeron en cinco grupos, cada uno con 14 aves. Cada grupo fue alimentado con una de las cinco dietas experimentales durante un período de 14 días. En el día 70 de edad, el alimento se retuvo durante 8 horas, momento en el que se recolectó una muestra de sangre, y luego se sacrificaron todos los pavos, se les realizó la necropsia y se tomaron muestras de diferentes tejidos. El peso de los diferentes órganos, los análisis de rendimiento, la bioquímica, la histopatología, el daño oxidativo y la toxicidad en testículos no revelaron efectos significativos atribuibles a micotoxinas de Fusarium. La medición de esfingolípidos en el hígado reveló un aumento en la relación de esfinganina con relación a la esfingosina en pavos alimentados con dietas que contenían fumonisinas, pero no tuvo consecuencias aparentes en términos de toxicidad. Finalmente, solo se encontraron ligeras diferencias en algunas variables y los resultados de este estudio no mostraron interacciones entre deoxinivalenol, fumonisinas y zearalenona. Tomados en conjunto, los resultados sugieren que los niveles máximos tolerados establecidos para la contaminación individual por deoxinivalenol, fumonisinas y zearalenona también pueden considerarse seguros en pavos alimentados con combinaciones de estas micotoxinas de Fusarium durante un período de 14 días.

Lack of Toxic Interaction Between Fusariotoxins in Broiler Chickens Fed throughout Their Life at the Highest Level Tolerated in the European Union.

Fusarium mycotoxins (FUS) occur frequently in poultry diets, and regulatory limits are laid down in several countries. However, the limits were established for exposure to a single mycotoxin, whereas multiple contamination is more realistic, and different studies have demonstrated that it is not possible to predict interactions between mycotoxins. The purpose of this study was thus to compare the toxic effect of deoxynivalenol (DON), fumonisins (FB) and zearalenone (ZON), alone and in combination on broiler chickens, at the maximum tolerated level established by the EU for poultry feed. Experimental corn-soybean diets incorporated ground cultured toxigenic Fusarium strains. One feed was formulated for chickens 0 to 10 days old and another for chickens 11 to 35 days old. The control diets were mycotoxin free, the DON diets contained 5 mg DON/kg, the FB diet contained 20 mg FB1 + FB2/kg, and the ZON diet contained 0.5mg ZON/kg. The DONFBZON diet contained 5, 20, and 0.5 mg/kg of DON, FB1 + FB2, and ZON, respectively. Diets were distributed ad libitum to 70 broilers (male Ross PM3) separated into five groups of 14 chickens each reared in individual cages from one to 35 days of age. On day 35, after a starvation period of 8 h, a blood sample was collected, and all the animals were killed and autopsied. No difference between groups that could be attributed to FUS was observed in performances, the relative weight of organs, biochemistry, histopathology, intestinal morphometry, variables of oxidative damage, and markers of testicle toxicity. A significant increase in sphinganine and in the sphinganine to sphingosine ratio was observed in broilers fed FB. Taken together, these results suggest that the regulatory guidelines established for single contamination of broiler chickens fed with DON, FB, and ZON can also be used in the case of multiple contamination with these toxins.

Author Correction: Metabolic changes in Medaka fish induced by cyanobacterial exposures in mesocosms: an integrative approach combining proteomic and metabolomic analyses.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Metabolic changes in Medaka fish induced by cyanobacterial exposures in mesocosms: an integrative approach combining proteomic and metabolomic analyses.

Cyanobacterial blooms pose serious threats to aquatic organisms and strongly impact the functioning of aquatic ecosystems. Due to their ability to produce a wide range of potentially bioactive secondary metabolites, so called cyanotoxins, cyanobacteria have been extensively studied in the past decades. Proteomic and metabolomic analyses provide a unique opportunity to evaluate the global response of hundreds of proteins and metabolites at a glance. In this study, we provide the first combined utilization of these methods targeted to identify the response of fish to bloom-forming cyanobacteria. Medaka fish (Oryzias latipes) were exposed for 96 hours either to a MC-producing or to a non-MC-producing strain of Microcystis aeruginosa and cellular, proteome and metabolome changes following exposure to cyanobacteria were characterized in the fish livers. The results suggest that a short-term exposure to cyanobacteria, producing or not MCs, induces sex-dependent molecular changes in medaka fish, without causing any cellular alterations. Globally, molecular entities involved in stress response, lipid metabolism and developmental processes exhibit the most contrasted changes following a cyanobacterial exposure. Moreover, it appears that proteomic and metabolomic analyses are useful tools to verify previous information and to additionally bring new horizons concerning molecular effects of cyanobacteria on fish.

Non-ocular melanomas in cats: a retrospective study of 30 cases.

Objectives The aim of the study was to describe the clinical outcome of 30 cats with non-ocular melanomas and to evaluate the association between clinical or pathological parameters and overall survival time. Methods The database of the animal histopathological laboratory of the National Veterinary School of Nantes (Oniris, Nantes, France) was retrospectively searched to identify cases of feline non-ocular melanomas between December 2009 and April 2014. For each case, clinical data, including signalment, location of the primary tumour, staging, treatment and outcome, were collected from the medical records or via interviews with referring veterinarians. Histological and immunohistochemical evaluation included mitotic index, cytonuclear atypias, junctional activity, Melan A and S100 immunostaining, and surgical margins. Univariate analysis to test the prognostic value of the different variables was performed by the Kaplan-Meier product limit method using the log-rank test of significance. Results Thirty cats were included in the study. Eleven had a cutaneous non-auricular melanoma, six had a tumour located on the pinna and 13 had a tumour in the oral cavity. Cats with auricular melanomas were significantly younger than cats with tumours in other locations. Location and presence of clinical signs were not of prognostic significance, but the achromic phenotype was significantly associated with a poorer prognosis. Twenty cats were treated with surgery and survived significantly longer than cats that received only medical treatment or that did not receive any treatment. According to our data, mitotic index, cytonuclear atypias, junctional activity, Melan A or S100 expression, and surgical margins were not associated with survival. Conclusions and relevance We show for the first time, in a large series, that the auricular form of melanoma affected significantly younger cats than other extraocular forms. Most feline non-ocular melanomas are malignant and achromic tumours are associated with a poorer prognosis. According to this study, surgery should be considered as a priority.

RESAMA: A Network for Monitoring Health and Husbandry Practices in Aquatic Research Facilities.

Health monitoring is a crucial aspect of the management of any research animal house. RESAMA is a network strong of 60 academic and private partners acting in France since the end of 2012. The network aims to increase awareness of animal caretakers and researchers on health management issues in facilities holding aquatic model species (zebrafish, Xenopus, medaka, Mexican tetra). To do so, each partner research facility will be visited at least once. The visiting team is composed at least of one veterinarian and one zootechnician specialized in aquatic species. The visit results in a health-monitoring assessment of the facility, which includes a sampling for histo-pathological, bacteriological, and molecular pathogen detection. During the visit, rearing practices are also reviewed through an interview of animal caretakers. However, the present report essentially focuses on the health-monitoring aspect. The ultimate goal of the project is to provide a network-wide picture of health issues in aquatic facilities. Performed in parallel, the rearing practice assessment will ultimately help to establish rational relationship between handling practices and animal health in aquatic facilities. The study is still in progress. Here, we describe the results to be drawn from an analysis of the 23 facilities that had been visited so far. We sampled 720 fish and 127 amphibians and performed a little less than 1400 individual tests.

RANAVIRUS CAUSES MASS DIE-OFFS OF ALPINE AMPHIBIANS IN THE SOUTHWESTERN ALPS, FRANCE.

Pathogenic fungi and viruses cause mortality outbreaks in wild amphibians worldwide. In the summer of 2012, dead tadpoles and adults of the European common frog Rana temporaria were reported in alpine lakes in the southwestern Alps (Mercantour National Park, France). A preliminary investigation using molecular diagnostic techniques identified a Ranavirus as the potential pathogenic agent. Three mortality events were recorded in the park, and samples were collected. The amphibian chytrid fungus Batrachochytrium dendrobatidis was not detected in any of the dead adult and juvenile frogs sampled (n=16) whereas all specimens were positive for a Ranavirus. The genome sequence of this Ranavirus was identical to previously published sequences of the common midwife toad virus (CMTV), a Ranavirus that has been associated with amphibian mortalities throughout Europe. We cultured virus from the organs of the dead common frogs and infecting adult male common frogs collected in another alpine region where no frog mortality had been observed. The experimentally infected frogs suffered 100% mortality (n=10). The alpine die-off is the first CMTV outbreak associated with mass mortality in wild amphibians in France. We describe the lesions observed and summarize amphibian populations affected by Ranaviruses in Europe. In addition, we discuss the ecologic specificities of mountain amphibians that may contribute to increasing their risk of exposure to and transmission of Ranaviruses.

Cancer: a missing link in ecosystem functioning?

Cancer is a disease that affects the majority of metazoan species and, before directly causing host death, is likely to influence the competitive abilities of individuals, their susceptibility to pathogens, their vulnerability to predators, and their ability to disperse. Despite the potential importance of these ecological impacts, cancer is rarely incorporated into model ecosystems. We describe here the diversity of ways in which oncogenic phenomena, from precancerous lesions to generalized metastatic cancers, may affect ecological processes that govern biotic interactions. We argue that oncogenic phenomena, despite their complexity, can have significant and sometimes predictable ecological consequences. Our aim is to provide a new perspective on the ecological and evolutionary significance of cancer in wildlife, and to stimulate research on this topic.

Primary meningeal T-cell lymphoma in a harbor seal (Phoca vitulina).

A 15-year-old female harbor seal (Phoca vitulina) was referred to the Nantes Veterinary School, Nantes, France, with a clinical history of anorexia, seizures, and left hemiplegia. Cerebrospinal fluid analysis revealed large numbers of neoplastic lymphoid cells. After injection of a contrast agent into the cerebrospinal space, radiographs demonstrated an asymmetry of the right lateral ventricle. Necropsy examination revealed a marked edema of the right frontal lobe, extending to the basal nuclei and thalamus in the brain. Histological examination of the brain revealed leptomeningeal lymphoma. Immunohistochemical labeling demonstrated that the neoplasm was of T-cell origin. No significant macroscopic or microscopic lesions were observed in the other organs examined, including lymphoid organs. This is the first report of primary leptomeningeal lymphoma in a harbor seal.