Gastropod-derived haemocyte extracellular traps entrap metastrongyloid larval stages of Angiostrongylus vasorum, Aelurostrongylus abstrusus and Troglostrongylus brevior

Background: Phagocyte-derived extracellular traps (ETs) were recently demonstrated mainly in vertebrate hosts as an important effector mechanism against invading parasites. In the present study we aimed to characterize gastropod-derived invertebrate extracellular phagocyte trap (InEPT) formation in response to larval stages of important canine and feline metastrongyloid lungworms. Gastropod haemocytes were isolated from the slug species Arion lusitanicus and Limax maximus, and the snail Achatina fulica, and exposed to larval stages of Angiostrongylus vasorum, Aelurostrongylus abstrusus and Troglostrongylus brevior and investigated for gastropod-derived InEPT formation. Results: Phase contrast as well as scanning electron microscopy (SEM) analyses of lungworm larvae-exposed haemocytes revealed ET-like structures to be extruded by haemocytes thereby contacting and ensnaring the parasites. Co-localization studies of haemocyte-derived extracellular DNA with histones and myeloperoxidase in larvae-entrapping structures confirmed classical characteristics of ETs. In vivo exposure of slugs to A. vasorum larvae resulted in InEPTs being extruded from haemocytes in the slug mucous extrapallial space emphasizing the pivotal role of this effector mechanism against invasive larvae. Functional larval entrapment assays demonstrated that almost half of the haemocyte-exposed larvae were contacted or even immobilized by released InEPTs. Overall, as reported for mammalian-derived ETs, different types of InEPTs were here observed, i.e. aggregated, spread and diffused InEPTs. Conclusions: To our knowledge, this study represents the first report on metastrongyloid lungworm-triggered ETosis in gastropods thereby providing evidence of early mollusc host innate immune reactions against invading larvae. These findings will contribute to the better understanding on complex parasite-intermediate host interactions since different gastropod species bear different transmitting capacities for metastrongyloid infections

Role of leptin and its receptor on bovine mammary gland

ABSTRACT: Leptin is a hormone-like protein involved in physiological processes related to the regulation of energy metabolism, reproduction, immunity, cancer, breastfeeding, among others. Leptin receptor is expressed in almost all tissues and generates six isoforms from a single mRNA. The predominant isoform in bovine mammary gland is the Ob-Rb, which triggers a signaling cascade through JAK-STAT molecules to induce proliferation, differentiation and apoptosis, according to the female reproductive stage. In small ruminants, such as sheep and goats, leptin and its receptor levels vary widely, being high at the beginning of pregnancy, tending to fall in mid-gestation, and remaining low until the end of lactation. An expression pattern of leptin receptor has not yet been established for the various reproductive stages in bovine mammary gland. Such study is considered important and necessary to understand the effect of leptin via its receptor in mammary gland, especially during lactation when the gland undergoes tissue remodeling to sustain high milk production. This review presents a hypothesis about the signaling pathway triggered by leptin receptor in the mammary gland during bovine lactation.RESUMEN: La leptina es una hormona proteínica que participa en procesos fisiológicos relacionados con la regulación del metabolismo energético, reproducción, inmunidad, cáncer, lactancia, entre otros. Su receptor se expresa en casi la totalidad de los tejidos, presentando seis isoformas a partir de un mismo ARNm. La isoforma predominante en la glándula mamaria bovina es la Ob-Rb, a través de la cual se puede desencadenar una cascada de señalización por medio de las moléculas JAK-STAT, para inducir proliferación, diferenciación y apoptosis celular de acuerdo al estadio reproductivo de la hembra. En pequeños rumiantes, tales como ovejas y cabras, los niveles de leptina y su receptor varían considerablemente durante la preñez y lactancia: son altos al inicio de la gestación, tienden a descender hasta la mitad de esta etapa y permanecen bajos hasta la finalización de la lactancia. En la glándula mamaria de bovinos aún no se ha establecido un patrón de expresión de los receptores durante diferentes etapas reproductivas, estudio que se considera importante y necesario para comprender el efecto de la leptina sobre su receptor en glándula mamaria, especialmente durante la lactancia, período durante el cual sufre una remodelación celular del tejido glandular para sostener una alta producción láctea. En la presente revisión se plantea una hipótesis de cómo podría ser la vía de señalización desencadenada por el receptor de leptina en la glándula mamaria durante la lactancia

Matemáticas en contexto

El libro compila estrategias didácticas derivadas del programa de formación complementario escritas por instructores técnicos de diferentes regionales del país, describe la forma en que se incorpora el conocimiento matemático en campos específicos de diferentes áreas de formación laboral basado en las teorías didácticas y reflexiones pedagógicas de instructores.The book compiles the didactic strategies derived from the complementary training program by the technical instructors of the regional media of the country, describes the way in which mathematical knowledge is incorporated in the fields of different areas of work training based on theories didactic and pedagogical reflections of instructors.Consideraciones frente al aprendizaje de las matemáticas -- Perspectiva constructivista -- Teoría de las situaciones didácticas -- Modelación matemática -- Mediación tecnológica -- Pensamiento numérico variacional -- Pensamiento numérico -- Pensamiento variacional -- Diseño de modelo matemático con aplicación de costos de producción -- Modelo matemático del consumo de gas en un artefacto afectado por su presión de trabajo -- Planeación de la producción agrícola: Caso plan óptimo de siembra que permita alcanzar la máxima rentabilidad del cultivo -- Estudio del Álgebra de Boole -- Diseño de un modelo de inventarios para una pequeña empresa de calzado de dotación -- Estudio de la Ley de Ohm mediante herramienta interactiva -- Pensamiento métrico-geométrico -- Pensamiento geométrico -- Pensamiento métrico -- Caso de optimización de recursos en el sector industrial de la confección -- Optimización de espacios para huertas urbanas -- Optimización de los costos del espacio de almacenamiento en microempresas y pequeñas empresas de acuerdo con las normas de seguridad vigentes -- Unidad de medida métrica para confección de ropa exterior femenina -- Optimización de recursos aplicando el proceso administrativo -- Pensamiento aleatorio -- Estadística Básica para Articulación con la Media -- Evaluación del impacto de la accidentalidad en la implementación del Sistema de Gestión de Seguridad y Salud en el Trabajo (sg-sst) por medio de indicadores -- Identificar los aspectos de la declaración de renta para una persona natural no obligada a llevar contabilidad -- Fortalecimiento de la estadística: caso de las unidades productivas del Centro de Biotecnología Agropecuaria -- Estadística dinámica -- Resultados preliminaresna[270 páginas

Mycotoxins, Phytoestrogens and Other Secondary Metabolites in Austrian Pastures: Occurrences, Contamination Levels and Implications of Geo-Climatic Factors

Pastures are key feed sources for dairy production and can be contaminated with several secondary metabolites from fungi and plants with toxic or endocrine-disrupting activities, which possess a risk for the health, reproduction and performance of cattle. This exploratory study aimed to determine the co-occurrences and concentrations of a wide range of mycotoxins, phytoestrogens and other secondary metabolites in grazing pastures. Representative samples of pastures were collected from 18 Austrian dairy farms (one sample per farm) between April to October 2019. After sample preparation (drying and milling) the pastures were subjected to multi-metabolite analysis using LC-MS/MS. In total, 68 metabolites were detected, including regulated zearalenone and deoxynivalenol (range: 2.16–138 and 107–505 μg/kg on a dry matter (DM) basis, respectively), modified (3-deoxynivalenol-glucoside, HT-2-glucoside) and emerging Fusarium mycotoxins (e.g., enniatins), ergot alkaloids and Alternaria metabolites along with phytoestrogens and other metabolites. Aflatoxins, fumonisins, T-2 toxin, HT-2 toxin and ochratoxins were not detected. Of the geo-climatic factors and botanical diversity investigated, the environment temperature (average of 2 pre-sampling months and the sampling month) was the most influential factor. The number of fungal metabolites linearly increased with increasing temperatures and temperatures exceeding 15 °C triggered an exponential increment in the concentrations of Fusarium and Alternaria metabolites and ergot alkaloids. In conclusion, even though the levels of regulated mycotoxins detected were below the EU guidance levels, the long-term exposure along with co-occurrence with modified and emerging mycotoxins might be an underestimated risk for grazing and forage-fed livestock. The one-year preliminary data points out a dominant effect of environmental temperature in the diversity and contamination level of fungal metabolites in pastures

Assessment of the risk of mycotoxins and other related contaminants in dairy cattle diets in Austria with relevance for cow health and fertility as well as food safety

Dissertation - Veterinärmedizinische Universität Wien - 2022Vor einigen Jahrzehnten ging man allgemein davon aus, dass Wiederkäuer gegen Mykotoxine resistent seien; diese Auffassung ist jedoch inzwischen überholt und veraltet. Obwohl über 400 Mykotoxinmetaboliten bekannt sind, haben sich die meisten Untersuchungen auf regulierte Mykotoxine fokussiert. Infolgedessen wurden die negativen Auswirkungen dieser Metaboliten von Milchviehhaltern und Tierärzten weltweit vernachlässigt und unterschätzt. Darüber hinaus scheinen die Stoffwechsel- und Ernährungsmerkmale von Hochleistungsmilchkühen (z. B. Futter mit hoher Energiekonzentration und höherer Passagerate) die Entgiftungskapazität des Pansens zu verringern, wodurch das Risiko subklinischer und klinischer Gesundheitsstörungen erhöht und die Fruchtbarkeit und Produktivität beeinträchtigt wird. Im Rahmen dieser Dissertation wurde in 100 Betrieben in den drei österreichischen Leitregionen der Milchproduktion (Steiermark, Nieder- und Oberösterreich) die Belastung eines breiten Spektrums von (toxischen) Pilzsekundärmetaboliten und anderen Kontaminanten in Milchviehfutter (Weiden, verschimmelte Silagen und Biertreber) und in Gesamtrationen untersucht. Die Analysemethode LC-MS/MS lieferte Profile von (toxischen) Metaboliten der Gattungen Fusarium, Alternaria, Aspergillus und Penicillium sowie Mutterkornalkaloide. Die Mykotoxinprofile der untersuchten Weiden, der Schimmelflecken in Mais- und Grassilage, des Biertrebers und der Gesamtrationen für Milchkühe zeigten das allgegenwärtige Vorhandensein komplexer Mischungen toxischer Pilzmetaboliten, wobei die von Fusarien stammenden dominierten. Die regulierten Mykotoxine DON, ZEN und FUM B1 kamen zu mehr als 70 % in den Futtermitteln vor. Die wichtigsten Faktoren, die den Mykotoxingehalt im Futter österreichischer Milchkühe beeinflussten, waren der Anteil von Maissilage und Stroh sowie die Umgebungstemperatur. Darüber hinaus wurde nachgewiesen, dass Maissilage und Stroh sowie die Umgebungstemperatur die Kontamination mit Fusarientoxinen und Metaboliten in den Gesamtrationen beeinflussen. Schimmelige Silage und BSG können ebenfalls ein Risiko für eine Exposition gegenüber Penicillium-Mykotoxinen darstellen. Insgesamt sind weitere Studien erforderlich, um die langfristigen Auswirkungen von Mischungen aus Mykotoxinen und anderen Kontaminanten auf die Tiergesundheit, Fruchtbarkeit und Lebensmittelsicherheit zu bewerten.Dissertation - University of Veterinary Medicine Vienna - 2022Some decades ago, ruminants were widely assumed to be resistant to dietary mycotoxins; however, this conception is now obsolete and antiquated. Although over 400 metabolites have been reported as mycotoxins, most investigations have focused on regulated fungal toxins. Consequently, the negative implications of these metabolites have been neglected and underestimated by dairy farmers and veterinarians worldwide. In addition, the metabolic and dietary characteristics of high-yielding dairy cattle (e.g., high energy density diets and higher passage rate) seem to reduce the detoxifying capacity of the rumen, thereby increasing the risk of subclinical and clinical health disorders, impairing fertility, and affecting productivity. This doctoral thesis focused on the assessment of the contamination levels of a broad spectrum of (toxic) fungal secondary metabolites and other contaminants in dairy feeds (pastures, mouldy silages and BSG) and complete dietary rations in 100 farms in the three Austrian regions leading milk production: Styria, Lower- and Upper Austria. The analytic method LC–MS/MS provided profiles of (toxic) metabolites derived from the genera Fusarium, Alternaria, Aspergillus and Penicillium, as well as ergot alkaloids. The mycotoxin profiles of the analysed pastures, mouldy spots of maize and grass silage, BSG and complete rations of dairy cattle evidenced the ubiquitous presence of complex mixtures of toxic fungal metabolites, dominated by Fusarium-derived ones. The regulated mycotoxins DON, ZEN and FUM B1, occurred >70% in the diets. The predominant factors influencing the content of mycotoxins in the diets of Austrian dairy cows were the co of maize silage and straw, as well as the environmental temperature. Additionally, it was demonstrated that maize silage and straw, as well as the environmental temperature, influenced the contamination with Fusariumderived toxins and metabolites in total rations. Mouldy silage and BSG can also risk of exposition to Penicillium mycotoxins. Taken together, further studies are needed to evaluate the long-term implications of mixtures of mycotoxins and other contaminants on animal health, fertility and food safety

Outbreak of aflatoxicosis in a dairy herd induced depletion in milk yield and high abortion rate in Pakistan

This case report investigated the outbreak of aflatoxicosis in a dairy herd in Pakistan, which resulted in 30 abortions of 40 confirmed (75%) pregnant cows in a period of 35 days and in 18.8% depression of farm average milk production for the entire herd. The analysis of the concentrate feed of the total mixed ration (TMR), using enzyme-linked immunosorbent assay (ELISA) procedures from two different local laboratories, indicated concentrations of 60 μg/kg dry matter (DM) of aflatoxin B1 (AFB1) and 100 μg/kg DM of total aflatoxins (AFs: sum of B1, B2, G1 and G2). Subsequently, a confirmatory analysis with a more sensitive and validated multi-metabolite liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was performed. This analysis detected a concentration of total AFs in the TMR of 166 μg/kg DM ± 3.5 (AFB1:134, AFB2:17.4 and AFM1:14.9 μg/kg DM). The concentrate feed (55% of the TMR DM) was confirmed as a source of contamination, presenting a concentration &gt;29 times higher than the EU-maximum limit value (5.68 μg/kg DM). Additionally, the multi-mycotoxin analysis evidenced the co-occurrence of 81 other toxic and potentially toxic fungal metabolites in the fed TMR. After replacing the contaminated concentrate feed with feedstuffs of the same formulation but from a new charge of ingredients, the abortion episodes ceased, and milk production increased significantly. In conclusion, the data of this case report suggest that AFs may be associated with pregnancy losses in dairy cattle and milk production depression. From the public health perspective, the data also indicate the need for a more careful examination of dairy animal feed in Pakistan. Since the high concentration of AFB1 detected in feed and considering the literature-reported transfer rates (1-6%) of this toxin to AFM1 (carcinogen for humans) in milk, the milk produced during the outbreak period is expected to be contaminated with AFM1, which raises public health concerns.<br/