Chemotactic response of the flavonoid daidzein and its effect on the composition of the rumen bacterial community

Daidzein is one of common metabolites in plants and has chemotactic effect on soil bacteria that colonize the plants. There are several tests to assess bacterial chemotaxis, but none focused on rumen bacteria. Therefore, the aim of this study was to test the chemotactic response of the rumen microflora towards daidzein using a standardized bacterial chemotaxis assay. It consisted in a modifying capillary technique and employing technology for measuring in vitro gas production. Ruminal fluids and cellulose were used as controls. The response of bacteria to daidzein was greater than the response to cellulose, supporting the hypothesis that when fodder is chewed by the ruminant it releases daidzein which can attract rumen bacteria towards feed particles (chemotaxis) for attachment and subsequent degradation

Harvest age of Urochloa hybrids regarding yield, chemical composition, and in vitro biogas production

Objective: To evaluate the chemical composition, fermentation, and in vitro biogas production of the Cayman and Cobra cultivars, at different cutting ages. Design/Methodology/Approach: Dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), hemicellulose (HEM), and cellulose (CEL) were determined at 28, 35, 42, and 49 cutting days. In vitro dry matter degradation (IVDMD), pH, and concentration of volatile fatty acids (VFA) were determined during fermentation. The biogas volume was estimated at 6, 12, 24, 48, and 72 hours; the volume of methane (CH4) and carbon dioxide (CO2) in the Cobra and Cayman forages was determined at 72 hours. A completely randomized design was used for the experiment. Results: There were no differences (P>0.05) in DM production during the different cutting ages. CP was higher (P<0.05) in both cultivars, at 28 and 35 days after the cutting. The NDF, ADF, HEM, and CEL percentages were different in both cultivars. IVDMD was higher (P<0.05) between day 28 and day 42. Finally, CH4 production was lower (P<0.05) at 28 and 35 days after the cutting. Study Limitations/Implications: The chemical composition of pastures is influenced by climate and, therefore, further analysis must be carried out during different periods or seasons of the year. Findings/Conclusions: The optimal cutting age of the Cobra and Cayman cultivars under drought conditions is between day 28 and day 35 of regrowth. During that period, they have the best chemical and fermentation characteristics

3er. Coloquio: Fortalecimiento de los Colectivos de Docencia

Las memorias del 3er. Coloquio de Fortalecimiento de Colectivos de Docencia deben ser entendidas como un esfuerzo colectivo de la comunidad de académicos de la División de Ciencias y Artes para el Diseño, en medio de la pandemia COVID-19, con el fin de: • Analizar y proponer acciones concretas que promuevan el mejoramiento de la calidad docente en la División. • Proponer acciones que permitan continuar fortaleciendo los cursos con modalidad a distancia (remotos). • Ante un escenario que probablemente demandará en el mediano plazo, transitar del modelo remoto a un modelo híbrido, proponer acciones a considerar para la transición de los cursos. • Planear y preparar cursos de nivelación de conocimientos, para cuando se transite a la impartición de la docencia de manera mixta o presencial, dirigidos a los alumnos que no hayan tenido oportunidad de desarrollar actividades relevantes para su formación, como prácticas de talleres y laboratorios, visitas, o alguna otra actividad relevante