Effect of Enterococcus faecium SF68 on growth performance and in vivo digestibility in buffalo calves

The effect of dietary supplementation with Enterococcus faecium strain SF68 on growth performance, faecal consistency and in vivo digestibility in buffalo (Bubalus bubalis) calves was evaluated. Forty calves were randomly assigned at 10 d of age to one of four treatments: (A) milk replacer with no additive, (B) milk replacer supplemented with 0.17 g/l of viable (2 x l09 cfu/g) E. faecium bacteria daily for 3 days with an interval of 7 days throughout 11 weeks, (C) milk replacer supplemented with E. faecium daily for 4 weeks, (D) milk replacer supplemented with E. faecium daily for 11 weeks. A total mixed ration was offered ad libitum from 5th week of the experimental period. Faecal score was significantly better in E. faecium-treated calves than control ones. The use of E. faecium had no effect on average daily gain at any stage, total body weight (BW) gain, dry matter intake or total tract digestibility. Therefore, E. faecium supplementation may be able to act favourably on the health of the gastro-intestinal trac

Fatty acid composition of Mediterranean buffalo milk fat

The purpose of this research was to investigate the variation in fatty acid composition of milk fat from four buffalo (Bubalus bubalis) herds under different feeding management and ration composition. Changes in milk fatty acid composition were monitored on a weekly basis. Saturated fatty acids (65.5%) predominated in buffalo milk fat; monounsaturated and polyunsaturated fatty acids were 27.0% and 4.5%, respectively. Of saturated fatty acids, the content of palmitic acid was the highest (30.6%) followed by stearic acid (12.0%) and myristic acid (10.7%). Of the unsaturated fatty acids the content of oleic acid was the highest (26.6%). The average content of conjugated linoleic acid (0.76±0.33) was higher than the maximal values generally reported for dairy cow

The elusive mitochondrial genomes of Apicomplexa: where are we now?

Mitochondria are vital organelles of eukaryotic cells, participating in key metabolic pathways such as cellular respiration, thermogenesis, maintenance of cellular redox potential, calcium homeostasis, cell signaling, and cell death. The phylum Apicomplexa is entirely composed of obligate intracellular parasites, causing a plethora of severe diseases in humans, wild and domestic animals. These pathogens include the causative agents of malaria, cryptosporidiosis, neosporosis, East Coast fever and toxoplasmosis, among others. The mitochondria in Apicomplexa has been put forward as a promising source of undiscovered drug targets, and it has been validated as the target of atovaquone, a drug currently used in the clinic to counter malaria. Apicomplexans present a single tubular mitochondria that varies widely both in structure and in genomic content across the phylum. The organelle is characterized by massive gene migrations to the nucleus, sequence rearrangements and drastic functional reductions in some species. Recent third generation sequencing studies have reignited an interest for elucidating the extensive diversity displayed by the mitochondrial genomes of apicomplexans and their intriguing genomic features. The underlying mechanisms of gene transcription and translation are also ill-understood. In this review, we present the state of the art on mitochondrial genome structure, composition and organization in the apicomplexan phylum revisiting topological and biochemical information gathered through classical techniques. We contextualize this in light of the genomic insight gained by second and, more recently, third generation sequencing technologies. We discuss the mitochondrial genomic and mechanistic features found in evolutionarily related alveolates, and discuss the common and distinct origins of the apicomplexan mitochondria peculiarities

Incidencia de la resolución de problemas en las transformación de las prácticas educativas para el desarrollo sostenible

En este trabajo de grado se presenta la descripción de cómo fue desarrollada la investigación; en primera instancia se hace una descripción general acerca de la resolución de problemas como estrategia didáctica para el desarrollo del pensamiento crítico y su relación con el aprendizaje de las ciencias. En segundo lugar, se describe el proceso por el cual esta investigación diseñó y aplicó estrategias didácticas en resolución de problemas en el área de ciencias naturales, con el objetivo de conocer la incidencia de la resolución de problemas en la transformación las prácticas educativas para el desarrollo sostenible a través del cambio en los modelos explicativos de los estudiantes de grado tercero y cuarto de primaria de dos instituciones educativas del departamento de Risaralda. Posee un tipo de estudio Cualitativo Descriptivo y con análisis de tipo mixto, la recolección y análisis de la información se llevó a cabo en 3 momentos con la utilización de 3 instrumentos: en el momento 1 se trianguló la información con el instrumento de indagación de ideas previas con respuestas tanto escritas como gráficas, en el momento dos con la intervención de la unidad didáctica y por último se realizó la aplicación del instrumento inicial de ideas previas con el fin de analizar el aprendizaje de las prácticas educativas información que se organizó en redes semánticas por estudiante. Resulta interesante la posibilidad de que esta investigación favorezca aproximaciones futuras referentes al tema ya que en este campo hay muy pocas investigaciones

Effect of Lupinus albus as protein supplement on yield, constituents, clotting properties and fatty acid composition in ewes' milk

The effect of feeding lupin seeds (Lupinus albus L.) as an alternative protein source in ewe diets was investigated. Two groups of 18 Sarda ewes were fed two different isonitrogenous diets: with lupin (L) seed, given after 12 h soaking, or soybean meal (SBM) as the main protein source. DMI, variations of body weight and milk production were unaffected by the treatment. Although not statistically significant, in the group fed L diet the production of milk fat and protein was higher. Clotting properties of milk were similar for the two treatments, probably due to the small differences in the milk protein contents. The fatty acid profile of milk was affected by treatment with a larger content of short (14.19 wt% versus 12.26 wt%)- and medium (49.37 wt% versus 47.76 wt%)-chain fatty acids in milk from ewes fed the L diet. CLA content was unaffected by treatment. Triglyceride content of fat from the two diets reflects the milk fatty acid composition. Indeed, milk from L diet showed a higher level of medium-chain triglycerides, which are of particular interest to consumers with concerns over health and heart disease. The inclusion of lupin seed in the diet of lactation ewes can be a means of achieving a more desirable triglyceride profile in milk fat. Milk with enhanced nutritive quality may promote wider market penetration of sheep dairy products

Paleoenvironment of the Toropí Formation (Upper Pleistocene), Corrientes province (Mesopotamian region, Argentina): A phytolith approach

Two Pleistocene sedimentary units are recognized in the Corrientes province, Argentina: the Toropí and Yupoí formations. These sediments have proven productive for fossil vertebrates, but few macrofossils have been recovered. To remedy this situation, plant silica (phytoliths) were extracted from the sediments, enabling a direct comparison of paleovegetation data and information based on previous study of vertebrates. The studied samples (n = 28) come from two profiles from the Toropí Stream (28°36'S; 59°02'W), near Bella Vista, Corrientes, from which two Quaternary mammals, Lestodon (Xenarthra) and Hippocamelus (Artiodactyla), have previously been excavated. All samples were productive and contained both non-plant biogenic silica (diatoms, sponge spicular, chrysophyte cysts) and phytoliths. Phytolith assemblages were dominated by morphotypes diagnostic of grasses, in particular C 3 pooids, C 4 chloridoids, and C 3 or C 4 panicoids (or related grasses in the PACMAD clade). Rare phytoliths of palms and other woody or herbaceous dicotyledonous angiosperms were also present. This combination of C 3 and C 4 grasses, and rare palms and other forest indicators, indicates grass-dominated habitats with groves with palms and other trees/shrubs along rivers, growing under a relatively warm and dry climate. This mixed plant community reflects shifting biogeographic affinity with the Chaco-Pampean plain and inter-tropical regions, respectively, linked to the frequent climatic-environmental fluctuations during the Late Pleistocene.Facultad de Ciencias Naturales y MuseoConsejo Nacional de Investigaciones Científicas y Técnica

Paleoenvironment of the Toropí Formation (Upper Pleistocene), Corrientes province (Mesopotamian region, Argentina): A phytolith approach

Two Pleistocene sedimentary units are recognized in the Corrientes province, Argentina: the Toropí and Yupoí formations. These sediments have proven productive for fossil vertebrates, but few macrofossils have been recovered. To remedy this situation, plant silica (phytoliths) were extracted from the sediments, enabling a direct comparison of paleovegetation data and information based on previous study of vertebrates. The studied samples (n = 28) come from two profiles from the Toropí Stream (28°36'S; 59°02'W), near Bella Vista, Corrientes, from which two Quaternary mammals, Lestodon (Xenarthra) and Hippocamelus (Artiodactyla), have previously been excavated. All samples were productive and contained both non-plant biogenic silica (diatoms, sponge spicular, chrysophyte cysts) and phytoliths. Phytolith assemblages were dominated by morphotypes diagnostic of grasses, in particular C 3 pooids, C 4 chloridoids, and C 3 or C 4 panicoids (or related grasses in the PACMAD clade). Rare phytoliths of palms and other woody or herbaceous dicotyledonous angiosperms were also present. This combination of C 3 and C 4 grasses, and rare palms and other forest indicators, indicates grass-dominated habitats with groves with palms and other trees/shrubs along rivers, growing under a relatively warm and dry climate. This mixed plant community reflects shifting biogeographic affinity with the Chaco-Pampean plain and inter-tropical regions, respectively, linked to the frequent climatic-environmental fluctuations during the Late Pleistocene.Facultad de Ciencias Naturales y MuseoConsejo Nacional de Investigaciones Científicas y Técnica

L’accès aux pratiques de fabrication de traces scripturales convenues au commencement de la forme scolaire

Cet article poursuit plusieurs objectifs : 1/ discuter le déplacement épistémologique et théorique que comporte l’étude d’une situation didactique empruntée à la Théorie des situations didactiques de Brousseau lorsqu’elle est étudiée comme une pratique d’enseignement ordinaire ; 2/ illustrer ce déplacement à travers l’analyse a priori d’une situation effectivement observée dans des classes genevoises d’école « enfantine » (maternelle) ; 3/ initier l’étude – éminemment comparatiste – du travail polyvalent du professeur au début de la scolarité (élèves de 4-5 ans) et en particulier poser la question du rôle fondateur des signes et des conditions didactiques de construction conjointe de traces scripturales utiles aux différents problèmes à traiter dans le domaine logico-mathématique mais aussi dans le domaine de l’accès aux premières écritures alphabétiques. L’article positionne un certain nombre d’ingrédients théoriques et en discute les soubassements épistémologiques, les compatibilités et les points aveugles. Il se termine avec le projet d’un travail intégratif visant l’articulation de théories complémentaires prenant en compte les pratiques de savoir (socio-historiquement situées et « reconstruites » dans le jeu de l’action conjointe), le travail des sémioses collectives et personnelles des agents, le jeu des formes instituées

La Metacomprensión como herramienta de desarrollo en la comprensión lectora en ciclo quinto del Colegio Nacional Nicolás Esguerra

El presente trabajo se origina en el Colegio Nacional Nicolás Esguerra de la ciudad de Bogotá en donde surge la necesidad de incrementar el nivel de comprensión lectora de textos narrativos en los estudiantes de la jornada nocturna del ciclo quinto, grupo 502, puesto que esta es una de las competencias más desempeñadas a nivel académico tanto en las instituciones privadas como públicas y en la que siguen manifestándose dificultades en su alcance. En este proyecto investigativo se buscará que los estudiantes en primer lugar, identifiquen y reconozcan la existencia de estrategias metacomprensivas. En segundo lugar que las apliquen a través de las clases de práctica y si es posible en cualquier momento de enfrentar un texto narrativo en sus tres etapas: la prelectura, la lectura y las poslectura. En tercer lugar que sean conscientes de que su uso será una herramienta de desarrollo para la mencionada comprensión lectora, y en último lugar que dichas estrategias implementadas a través de talleres interactivos fomenten su interés hacia la lectura y en ese sentido incrementen la competencia de la argumentación en el nivel de expresión de un punto de vista y adopción de una postura frente a las diversas temáticas presentes en las lecturas.Universidad Libre - Facultad Ciencias de la Educación - Licenciatura en educación básica con énfasis en humanidades e idioma

Reevaluation of the Toxoplasma gondii and Neospora caninum genomes reveals misassembly, karyotype differences, and chromosomal rearrangements

Neospora caninum primarily infects cattle, causing abortions, with an estimated impact of a billion dollars on the worldwide economy annually. However, the study of its biology has been unheeded by the established paradigm that it is virtually identical to its close relative, the widely studied human pathogen Toxoplasma gondii. By revisiting the genome sequence, assembly, and annotation using third-generation sequencing technologies, here we show that the N. caninum genome was originally incorrectly assembled under the presumption of synteny with T. gondii. We show that major chromosomal rearrangements have occurred between these species. Importantly, we show that chromosomes originally named Chr VIIb and VIII are indeed fused, reducing the karyotype of both N. caninum and T. gondii to 13 chromosomes. We reannotate the N. caninum genome, revealing more than 500 new genes. We sequence and annotate the nonphotosynthetic plastid and mitochondrial genomes and show that although apicoplast genomes are virtually identical, high levels of gene fragmentation and reshuffling exist between species and strains. Our results correct assembly artifacts that are currently widely distributed in the genome database of N. caninum and T. gondii and, more importantly, highlight the mitochondria as a previously oversighted source of variability and pave the way for a change in the paradigm of synteny, encouraging rethinking the genome as basis of the comparative unique biology of these pathogens.INIA: FSSA_X_2014_1_10602