Utilització dels antimicrobians en veterinària i l'ús prudent dels antibiòtics

La utilització dels antimicrobians en producció animal ha suposat un gran avanç en la reducció dels problemes infecciosos dels animals que es fan servir com a font fonamental de proteïna d'origen animal. Aquesta reducció dels problemes infecciosos comporta a més una reducció del risc de transmissió d'infeccions als consumidors i, per tant, un augment en la seguretat de la cadena alimentària. L'ús dels antimicrobians porta implícita l'aparició de resistències. Per tal de minimitzar el risc d'aparició de resistències i controlar-ne la disseminació, cada vegada és més important implementar unes pautes de comportament que incloguin un ús prudent dels antimicrobians.Antimicrobial use in animal production has lead to a great reduction of infectious diseases in animals used as protein source. Additionally to the reduction of infectious disorders, a reduction of transmission risks of infectious agents to consumers is also achieved and, also, an increase in food chain safety. Antimicrobial use is always related to resistance generation. In order to minimise the appearance risk of these resistances and to control their spread, it is very important to implement guidelines to force a prudent use of antimicrobials

Colonization capacity and serum bactericidal activity of Haemophilus parasuis thy mutants

The bacterial thyA gene encodes the enzyme thymidylate synthase, which is essential for dTMP synthesis and, consequently, for DNA replication. In this work, a Haemophilus parasuis thyA mutant was constructed in order to analyze its colonization characteristics and its capacity to generate serum bactericidal activity in infected guinea pigs. The data showed that colonization by the H. parasuis thyA mutant was much less than that of the wild-type strain. Nevertheless, the mutant generated a strong immunogenic response in the host, as detected by measuring serum bactericidal activity. [Int Microbiol 2006; 9(4):297-301

Neurocranial bones are key to untangling the sea cow evolutionary tree: osteology of the skull of Sobrarbesiren cardieli (Mammalia: Pan-Sirenia)

The pan-sirenian Bauplan is conservative, probably owing to the constraints of adaptation to an aquatic lifestyle. Gathering morphological data from extinct forms is complex, resulting in poorly resolved phylogenies for stem pan-sirenians. Extant sirenians ossify the falx cerebri and the tentorium cerebelli, membranes of the dura mater of the brain attached to the parietal bone. Nevertheless, these ossifications are not present in some pan-sirenians. The basioccipital bone has received little attention in the literature except for establishing the relative age of individuals. Here, we present new cranial elements and a detailed description of the skull of Sobrarbesiren cardieli, a stem pan-sirenian from the Lutetian of Spain represented by eight individuals; we study its intraspecific variation and palaeoecological implications and explore the evolution of the endocranial structures and the basioccipital bone in pan-sirenians. Six new phylogenetic characters are added to the latest pan-sirenian dataset, resulting in a well-resolved topology where Sobrarbesiren is recovered close to the root, in a clade with Prototherium and Eotheroides aegyptiacum. The basioccipital bone and the ossified endocranial membranes have a phylogenetic signal, and the absence of such endocranial structures represents the plesiomorphic condition for pan-sirenians and is not diagnostic for the family Protosirenidae as previously believed

Heterologous protective immunization elicited in mice by Pasteurella multocida fur ompH

Different strategies have been developed to produce vaccines against Pasteurella multocida. The approach described herein involves overexpression on the bacterial cell surface of Fur-regulated IROMPs (iron-regulated outer-membrane proteins). Accordingly, the ability of fur mutants to promote heterologous protection was examined in a Swiss mouse animal model. Two fur mutants derived from P. multocida were isolated, one of which was also defective in the OmpH protein. In mice challenged with virulent P. multocida, outer-membrane protein (OMP) extracts of fur cells conferred the same protection as obtained with wild-type cells grown in iron-depleted medium. Total protection was achieved with 40 μg of OMP extract from the fur ompH mutant. Mice administered heat-inactivated fur ompH cells were 60% cross-protected. The presence of a galE mutation in these cells did not further increase the protection level. Additionally, cell disruption by sonication provoked a higher level of protection than conferred by heat-treated cells. Taken together, the results showed that P. multocida fur ompH cells offer a simple and suitable approach for cross-protecting animals against infection with P. multocida. [Int Microbiol 2008; 11(1):17-24

Influence of dietary n-3 long-chain fatty acids on microbial diversity and composition of sows’ feces, colostrum, milk, and suckling piglets’ feces

Introduction: Very little is known about the impact of n-3 long-chain fatty acids (n-3 LCFAs) on the microbiota of sows and their piglets. The aim of this study was to evaluate the effect of n-3 LCFA in sow diets on the microbiota composition of sows’ feces, colostrum, and milk as well as that of piglets’feces. Methods: Twenty-two sows were randomly assigned to either a control or an n-3 LCFA diet from service to weaning. Sows’ and piglets’ performance was monitored. The gestating and lactating sows’microbiomes in feces, colostrum, and milk were characterized by 16s ribosomal RNA gene sequencing. The fecal microbiome from the two lowest (>800 g) and the two highest birth weight piglets per litter was also characterized, and the LPS levels in plasma were analyzed at weaning. Results and Discussion: n-3 LCFA increased microbiota alpha diversity in suckling piglets’ and gestating sows’ feces. However, no effects were observed in colostrum, milk, or lactating sows’ feces. Dietary n-3 LCFA modified the microbiota composition of gestating sows’ feces, milk, and suckling piglets’feces, without affecting lactating sows’ feces or colostrum. In gestating sows’ feces and milk, the decrease in genus Succinivibrio and the increase of Proteobacteria phylum, due to the increased genera Brenneria and Escherichia, respectively, stand out. In the feces of suckling piglets, the higher abundance of the beneficial genus Akkermansia and Bacteroides, and different species of Lactobacillus are highlighted. In addition, positive correlations for families and genera were found between lactating sows’ feces and milk, milk and suckling piglets’ feces, and lactating sows’ feces and suckling piglets’feces. To conclude, dietary n-3 LCFA had a positive impact on the microbiome of suckling piglet’s feces by increasing microbial diversity and some beneficial bacteria populations, had a few minor modifications on the microbiome of milk and gestating sows’ feces and did not change the microbiome in lactating sows’ feces or colostrum. Therefore, this study shows the effect of dietary n-3 LCFA on the microbiota of sows, colostrum, milk, and suckling piglets during the lactation period providing crucial information on the microbiota status at the early stages of life, which have an impact on the post-weaning.info:eu-repo/semantics/publishedVersio

Reconstruyendo el mundo perdido de los dinosaurios

El interés por los vertebrados fósiles es cada vez mayor, y raro es el día que no surge alguna noticia de un nuevo descubrimiento, especialmente en dinosaurios. Los investigadores en Paleontología nos dedicamos a reconstruir los ecosistemas del pasado y conocer su evolución. El grupo Aragosaurus es un equipo de investigación de la Facultad de Ciencias integrado en el Instituto de Ciencias Ambientales de Aragón (IUCA) en el que se incluyen investigadores de otras universidades españolas. Una de nuestras líneas de trabajo son los vertebrados fósiles del Mesozoico, un periodo de tiempo comprendido entre los 250 y 65 millones de años (Ma), y que es conocido como la era de los dinosaurios. Estos animales se integraban en ecosistemas tan complejos como los actuales. Reconstruimos su Paleobiología basándonos en estudios filogenéticos, anatómicos y biomecánicos de los huesos, además de las evidencias de su actividad orgánica conservadas en pisadas fosilizadas (icnitas) y cáscara de huevo.Además de los dinosaurios también estudiamos el resto de los vertebrados fósiles que formabanlos ecosistemas del Mesozoico como son los tiburones y otros peces, cocodrilos, reptiles voladores, mamíferos, anfibios y lagartos. Nuestro objetivo global es aportar información para reconstruir el mundo perdido de los dinosaurios. Fruto del interés social por estas investigacioneses la frecuencia con la que han aparecido reseñas de prensa con los resultados del trabajo de investigación de nuestro grupo en los últimos meses. Queremos compartir con los lectores de conCIENCIAS un resumen de los descubrimientos más singulares y significativos ordenados demás antiguos a más modernos. Fil: Canudo, José Ignacio. Universidad de Zaragoza. Facultad de Ciencias; EspañaFil: Badiola, Ainara. Universidad del País Vasco, Facultad de Ciencias y Tecnología; Países BajosFil: Barco, José Luis. Universidad de Zaragoza. Facultad de Ciencias; EspañaFil: Castanera, Diego. Universidad de Zaragoza. Facultad de Ciencias; EspañaFil: Cruzado Caballero, Penélope. Universidad de Zaragoza. Facultad de Ciencias; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigación en Paleobiología y Geología; ArgentinaFil: Díaz, Ester. Universidad de Zaragoza. Facultad de Ciencias; EspañaFil: Díaz, Ignacio. Universidad de la Rioja, Facultad de Ciencias, Estudios Agroalimentarios e Informática; ArgentinaFil: Gasca, José Manuel. Universidad de Zaragoza. Facultad de Ciencias; EspañaFil: Moreno Azanza, Miguel. Universidad de Zaragoza. Facultad de Ciencias; EspañaFil: Parrilla, Jara. Universidad de Zaragoza. Facultad de Ciencias; EspañaFil: Puértolas Pascual, Eduardo. Universidad de Zaragoza. Facultad de Ciencias; EspañaFil: Ruiz Omeñaca, José Ignacio. Museo Jurásico de Asturias; EspañaFil: Vila, Bernat. Universidad de Zaragoza. Facultad de Ciencias; EspañaFil: Cuenca, Gloria. Universidad de Zaragoza. Facultad de Ciencias; Españ

Myxomatosis and rabbit Haemorrhagic disease: A 30-year study of the occurrence on commercial farms in Spain

In this retrospective study, we describe the relative occurrence of clinical myxomatosis, and rabbit haemorrhagic disease (RHD), on 1714 commercial farms visited in Spain, between 1988 and 2018. We determined the annual prevalence based on 817 visits to 394 farms affected by myxomatosis. Myxomatosis was more prevalent from August to March, being lowest in June (3%) and highest in September (8.9%). With regard to RHD, we assessed 253 visits to 156 affected farms. We analyzed mean annual and monthly incidence. Two important RHD epidemics occurred; the first in 1988-1989 due to RHDV GI.1 (also known as RHDV), and the second from 2011 to 2013 due to RHDV GI.2 (RHDV2 or RHDVb). These epidemics occurred at times when effective vaccination had not been carried out. Relative monthly incidence in 2011-2018 was higher from April to August (p < 0.001). The results we obtained from 1404 necropsies on 102 farms did not clearly relate serosanguinous nasal discharge in rabbits with disease caused by GI.2 infection. We also assessed vaccination schedules used on 200 doe farms visited from the end of 2014 to 2018; 95.5% vaccinated against myxomatosis and 97.5% against RHD. Both diseases remain prevalent; however, effective vaccination has produced a steady decline in myxomatosis and RHDV GI.1 and GI.2 on-farm detection. The maintenance of high hygienic standards will be needed to continue and improve this control. However, further studies are required to investigate the causes of sustained virus presence and vaccine breaks.info:eu-repo/semantics/publishedVersio

Estudio de rutas de vacunación en modelo murino para el uso profiláctico o terapéutico de vacunas atenuadas de tuberculosis

La tuberculosis es una de las enfermedades infecciosas que produce mayor mortalidad en el mundo. El agente causante es Mycobacterium tuberculosis que convive estrechamente con el hombre desde sus inicios como Homo sapiens. De momento, la única vacuna disponible es BCG (derivada de Mycobacterium bovis) pero esta no es efectiva contra la tuberculosis pulmonar en adultos, que es además la forma responsable de la transmisión de la enfermedad. Actualmente muchos equipos de investigación están trabajando en el desarrollo de nuevas vacunas y tratamientos eficaces, siendo MTBVAC la única vacuna candidata basada en la atenuación del agente patógeno causante de la tuberculosis humana. La eficacia de esta vacuna está siendo actualmente estudiada en ensayos clínicos en Fase III de eficacia. Previo a la fase clínica todos los estudios conllevan una fase de estudios preclínicos in vitro y después en animales de experimentación. El modelo murino es el modelo de elección en animales de experimentación, principalmente por su facilidad de manejo, economía de estabulado y disponibilidad de reactivos específicos de ratón para estudios inmunológicos. En esta tesis relacionamos distintos modelos de experimentación en ratones para lo cual hemos seleccionado 4 estudios de investigación basados en las vacunas vivas atenuadas MTBVAC y BCG. <br /

Mechanical and electrical properties of additively manufactured copper

Additive Manufacturing (AM) has become the new paradigm of design and production strategies. While structural and functional materials are the most implemented ones, it is also possible to manufacture parts using precious metals, being copper one of the most interesting. Among AM technologies, the novel Atomic Diffusion Additive Manufacturing (ADAM) hasrecently included this material between available ones. ADAM is free from thermal and energetic issues caused by high reflectivity and conductivity of copper which other AM encounter. Therefore, it could be a great alternative to manufacture pure copper. In this work ADAM was used to fabricate pure copper specimens in order to measure electrical and mechanical properties. The influence of a machining post processes in strength and ductility is also discussed. Results are compared with wrought C1 1000 copper and published results of other AM technologies. Despite the newness of ADAM, significant improvement in surface roughness and comparable results in other properties was observed. However, further research shall be done to optimize the manufacturing parameters in order to increase the relative density value, as it was found to be significantly lower than in other AM technologies