Promoción de raigrás anual naturalizado (Lolium multiflorum L.) en la cuenca del río Salado. Evaluación de la producción invernal de forraje en pastoreo

Effective operation of grazing production systems needs control the production of forage at farm level. A nine year old stand of enhanced tame native ryegrass (Lolium multiflorum L.) (RGE) and an annual crop of Italian ryegrass (Lolium multiflorum L. cv Tama) (RGT) were monitored to test the hypothesis that: (i) herbage biomass in such pastures can be assessed by Ration Calculation methodology as accurately as by more exhaustive procedures, and (ii) enhancement increases amount and quality of forage winter supply. Enhancement includes fertilization with NH4 NO3 and (NH4 ) 2 HPO4, and weed control with Glyphosate (N- (phosphonomethyl glycine)). The Ration Calculation method estimates available herbage dry matter assuming that «one herbage ration» equal to one cow equivalent (CE), consisting of 10 kg DM day-1 with 77.57 MJ of ME. Herbage samples were taken from each paddock, representing harvestable biomass. Grazing harvest efficiency and herbage DM intake (HDMI) were estimated through difference between initial (IHA) and final (FHA) herbage available (kg DM ha-1), before and after grazing, corrected by losses due to grazing. Eight grazing cycles of RGE produced 16 041 kg DM/ha year-1, (2 001 ± 79.3 rations/ha year-1) while ration calculation estimates 9 775 kg DM/ha year-1. The RGT allowed seven grazing cycles, yielded 12 269 kg DM/ha year-1 or 1 144 ± 87.1 rations/ha year-1 compared to 8 688 kg DM/ha year-1 estimated by calculating ration. The ration calculation method did not accurately assess the enhanced cumulative herbage DM produced. Enhancement technology improved production and quality of tame ryegrass in winter time.El manejo de sistemas ganaderos de producción requiere controlar la producción de forraje a nivel de unidad de pastoreo. Con una pastura naturalizada y promocionada durante nueve años de raigras (Lolium multiflorum L.) (RGE) y un cultivo de raigras anual (Lolium multiflorum L. cv. Tama) (RGT) se probaron las hipótesis de que la biomasa forrajera aerea puede ser estimada correctamente por el método del cálculo de raciones como mediante los atributos del forraje, y que la promoción permite aumentar la producción invernal de forraje. La promoción involucra fertilizaciones con NH4 NO3 y (NH4 )2 HPO4 y control de malezas con Glifosato (N- (phosphonomethyl glycine). La estimación de materia seca disponible mediante el calculo de raciones asume que «una ración de forraje» son 10 kg MS día-1 que contienen 77.57 MJ de EM que representan un equivalente vaca (CE). La eficiencia de cosecha y consumo en pastoreo (HDMI) fueron estimados por diferencia entre disponibilidad forrajera inicial (IHA) y final (FHA) antes y después del pastoreo, corregido por pérdidas debidas al pastoreo. El período de crecimiento de la RGE permitió ocho pastoreos produciendo 16 041 kg MS/ha año-1 ó 2 001± 79.3 raciones/ha año-1 comparado con 9 775 kg MS/ha año-1 estimados por cálculo de raciones. En siete pastoreos el RGT produjo 12 269 kg MS/ha año-1 ó 1 144 raciones/ha año-1, comparado con 8 688 kg MS/ha año-1 estimados por el cálculo de raciones. Se concluye que el cálculo de raciones no estima correctamente la biomasa producida por una promoción y que, efectivamente, la tecnología de promoción aumenta la producción y calidad invernal del pastizal natural.Fil: Danelon, Jose Luis. Universidad de Buenos Aires. Facultad de Agronomía; ArgentinaFil: Magaz, Santiago Horacio. Universidad de Buenos Aires. Facultad de Agronomía; ArgentinaFil: Magaz, Hernan Miguel. Universidad de Buenos Aires. Facultad de Agronomía; ArgentinaFil: Colombatto, Dario. Universidad de Buenos Aires. Facultad de Agronomía; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Calculating economic values for milk components in a pasture-based-dairy-system: the case of Argentina

Economic values (EV) of milk components (P: protein, F: fat and V: volume ) were obtained for a dairy system based on pasture, where a large proportion of milk is sold to industry. The EV’s were calculated using a profit function with a restriction in total feed supply. Economic value of protein (EVP) had the largest absolute and relative standardized values. Economic value of volume (EVV) was always small and negative. Multiple regression analyses of EV’s showed all EV’ s to be affected (P<.01) by the ratio of price of protein to price of fat ($P:$F) and level of production. The effects of $P:$F were linear and quadratic, whereas those of level of production were linear. Prediction equations obtained in the study can be used to calculate EV’s for different pricing systems and levels of milk production under grazing systems in Argentina

Comparison of enhanced, tame Italian ryegrass (Lolium multiflorum L.), long established and naturally reseeded, versus an annual ryegrass crop in the flood plain of Río Salado, Argentina: Winter forage production under grazing

Effective operation of grazing production systems requires controlling forage availability at the farm level. A nine-year-old stand of enhanced native ryegrass (Lolium multiflorum L.) (RGE) and an annual crop of Italian ryegrass (Lolium multiflorum L. cv Tama) (RGT) were monitored to test the hypotheses that: (1) herbage biomass in such pastures can be assessed by Ration Calculation methodology as accurately as by more exhaustive procedures, and (2) enhancement increases quantity and quality of the winter forage supply. Enhancement includes fertilization with NH4NO3 and (NH4)2HPO4, and weed control with Glyphosate. The Ration Calculation method estimates available herbage dry matter assuming that «one herbage ration» is equal to one cow equivalent (CE), consisting of 10 kg DM day-1 with 77.57 MJ of ME. Herbage samples were taken from each paddock, representing harvestable biomass. Grazing harvest efficiency and herbage DM intake (HDMI) were estimated through the difference between initial (IHA) and final (FHA) herbage available (kg DM ha-1), before and after grazing, corrected for losses due to grazing. Eight grazing cycles of RGE produced annually 16 041 kg DM/ha, (2 001 ± 79.3 rations/ha) while ration calculation estimated 9 775 kg DM/ha. The RGT allowed seven annual grazing cycles, yielded 12 269 kg DM/ha or 1 144 ± 87.1 rations/ha compared to 8 688 kg DM/ha estimated by calculating rations. The latter method did not accurately assess the enhanced cumulative herbage DM produced. Enhancement technology improved production and quality of tame ryegrass in winter

Technical Note: Comparison of three analytical procedures to estimate the acid detergent fiber concentration in feeds of widespread use in Argentina

El objetivo de este trabajo fue comparar la determinación del contenido de fibra insoluble en detergente ácido (FDA) en alimentos muy utilizados en Argentina, mediante tres procedimientos analíticos diferentes.Los procedimientos comparados fueron dos involucrando la técnica de las bolsas filtrantes ANKOM (FBT) consistentes en el tratamiento directo de las muestras con solución detergente ácido (D-ADF), y en el tratamiento secuencial primero con detergente neutro seguido de detergente ácido todo sobre la misma muestra (S-ADF). El tercer procedimiento fue la técnica tradicional de Van Soest utilizando crisoles de capa filtrante (VS-FDA). Los materiales analizados, elegidos debido a su gran difusión para la alimentación del ganado fueron: Harina de soja, granos de maíz y semillas de girasol, pasto fresco de agropiro alargado (Thinopyrum ponticum), alfalfa (Medicago sativa), pasto guinea (Panicum maximum), cebada (Hordeum vulgare), pasto llorón (Eragrostis curvula Nees) y raigrass annual (Lolium multiflorum), y ensilajes de maíz y de pasturas perennes consociadas. Por cada procedimiento y alimento se practicaron cuatro corridas analíticas. Los análisis estadísticos mostraron que los resultados de S-ADF difirieron tanto de VS-FDA como de D-FDA. Se encontraron altas correlaciones lineales (R2 > 0.99) entre VS-ADF y D-ADF con S-ADF. Sin embargo, las diferencias encontradas entre los procedimientos para algunos de los alimentos indican que la metodología utilizada para evaluar el contenido ADF deberá ser claramente identificada al reportar resultadosThe objective of this study was to compare the values of acid detergent fiber (ADF) content in feeds widely used in Argentina obtained using three different analytical procedures. Two of these involved use of the ANKOM® filter bag technique: direct treatment of the feed samples with acid detergent solution (D-ADF) in one case or sequential treatments with neutral detergent followed by acid detergent solution (S-ADF) in the other. The third procedure was the traditional Van Soest using filtering glass crucibles (VS-ADF). Materials analyzed, chosen because of their extensive use for cattle feeding in Argentina, were: soybean meal, whole corn grain, whole sunflower seed, fresh forages of tall wheatgrass (Thinopyrum ponticum), alfalfa (Medicago sativa), guinea grass (Panicum maximum), barley grass (Hordeum vulgare), weeping lovegrass (Eragrostis curvula) and Italian ryegrass (Lolium multiflorum), and silages of corn and mixed legume-grass forages. Four runs were performed for each procedure and feed. Statistical comparisons showed that S-ADF results differed (P< 0.001) from those of both VS-ADF and D-ADF. High linear relationships (R2 > 0.99) were found between both VS-ADF and D-ADF values and those of S-ADF. However, between-procedure differences found for some of the feeds analyzed indicate that the methodology used for ADF determination should be clearly identified when reporting results

Supplementation of alfalfa silage with different energy-rich concentrates in diets for lactating dairy goats

Lactating Saanen does were fed diets based on ad libitum alfalfa silage (SA) to study the effects of including fixed amounts of three different energy-rich concentrates: wheat grain (T), sorghum grain (S), and dehydrated citrus pulp (PC), in a 4 x 4 Latin Square with four replicates. Sixteen does (45 ± 10 d postpartum and producing 2.016 ± 0.58 kg/d of 4% fat corrected milk, FCM) housed in individual pens under roof, received the following diets: 1) SA (33.9% DM, 19.9% CP, 44% NDF); 2) SAT (52.4% DM, 19.8% CP, 33.7% NDF); 3) SAS (50.9% DM, 17.9% CP, 37% NDF); and 4) SAPC (52.5% DM, 16.1% CP, 39.1% NDF), resulting in respective forage-to-concentrate ratios (F:C) of 100:0. 65:35, 67:33, and 64:36. Daily DM intake from silage was greater for SA than for the other three treatments combined (2.55 vs. 2.33% of body weight, BW) whereas total DM intake (g/kg BW0.75) was lower (74.9 vs. 95.4). Yields of FCM or fat-protein-corrected milk were affected positively by concentrate supplementation, but milk protein concentration (g/L) or yield (g/d) were not. Chewing efficiency (min/g NDF consumed per kg BW0.75) improved from 20.4 to 15.0 (P <0.05) as a result of F:C decrease from 100:0 to 65:35, independent of the type of concentrate supplementation. Results suggest that the daily feeding routine (four offerings of alfalfa silage and two of concentrates) had greater impact on animal performance than the physical-chemical properties of dietary concentrates. In this study levels of 20 to 27% ADF and 33 to 44%NDF in diets for Saanen goats proved to be adequate to maintain normal rumen function and productive performance

Crianza artificial de terneros de tambo utilizando sustitutos lácteos de distinto contenido energético

El objetivo de este trabajo fue evaluar la respuesta productiva de terneros machos alimentados con 3 dietas líquidas diferentes más un alimento balanceado comercial. Los sustitutos lácteos utilizados fueron: 1) sustituto convencional, de composición similar a los comúnmente encontrados en el mercado (20% PB y 15% EE), y 2) otro con mayor contenido de grasa (20% PB y 20% EE). Como testigo se alimentó un grupo con leche proveniente del tambo. Se evaluó el tiempo al desleche, ganancia diaria de peso vivo (GDPV), consumo de materia seca (CMS) y nutrientes, y eficiencia de conversión. Se utilizaron 21 terneros machos de raza Holando-Argentino provenientes de una explotación comercial del Partido de Luján (7 por tratamiento), los cuales fueron criados en sistema de estaca durante 60 días. Se realizaron mediciones del consumo de alimento sólido y líquido diariamente, y aumento de peso cada 21 días. Los resultados obtenidos muestran que no hubo diferencias significativas entre tratamientos para ninguna de las variables analizadas, excepto en la eficiencia de conversión (kg MS/kg ganancia de peso total) y en la GDPV entre los días 3 y 24, la cual fue mayor para el tratamiento testigo leche en ambos casos. Se concluye que a pesar de que los sustitutos lácteos analizados no logran equiparar la GDPV y la conversión con respecto al grupo testigo durante los primeros 24 días, todos los tratamientos presentaron un comportamiento productivo similar en la totalidad de la crianza.The aim of this study was to evaluate the growth performance of male calves fed 3 different liquid diets plus a commercial feed. Milk replacers used were: 1) conventional milk replacer, similar to those commonly found in the market (20 % CP and 15 % EE), and 2) one with higher fat content (20 % CP and 20 % EE). The control group was fed with whole milk. We evaluated time to weaning, daily live weight gain (DLWG), dry matter intake (DMI) nutrients intake, and conversion efficiency. We used 21 Holstein male calves from a dairy farm in Luján (Buenos Aires, Argentina) (7 per treatment) reared outside with bucket system. Weight gain measurements were made every 21 days, solid and liquid feed intakes were measured daily. The results show no significant differences between treatments for any of the variables analyzed, except the conversion efficiency (kg DM/ kg total weight gain) and daily weight gain between days 3 and 24, which was higher for control group in both cases. We conclude that although milk replacers evaluated fail to equate conversion and DLWG compared with the control group during the first 24 days, all treatments had a similar performance overall.Fil: Juliano, Nicolas. Universidad de Buenos Aires. Facultad de Agronomia. Departamento de Producción Animal. Cátedra de Producción Lechera; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Danelon, Jose Luis. Universidad de Buenos Aires. Facultad de Agronomia. Departamento de Producción Animal. Cátedra de Nutrición Animal; ArgentinaFil: Fattore, Gisel Lorena. Eurotec Nutrition Argentina; ArgentinaFil: Cantet, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Agronomia. Departamento de Producción Animal. Cátedra de Nutrición Animal; ArgentinaFil: Martinez, R.. Universidad de Buenos Aires. Facultad de Agronomia. Departamento de Producción Animal. Cátedra de Nutrición Animal; ArgentinaFil: Miccoli, Florencia Estefania. Universidad de Buenos Aires. Facultad de Agronomia. Departamento de Producción Animal. Cátedra de Nutrición Animal; ArgentinaFil: Palladino, Rafael Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Unidad Ejecutora de Investigaciones en Producción Animal. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias. Unidad Ejecutora de Investigaciones en Producción Animal; Argentin

An alkaloid extract obtained from Phlegmariurus Saururus induces neuroprotection after status epilepticus

Background The brain is exposed to many excitotoxic insults that can lead to neuronal damage. Among these, Epilepsy is a neurological disease that affects a large percentage of world population and is commonly associated with cognitive disorders and excitotoxic neuronal death. Most experimental strategies are focused on preventing Status Epilepticus (SE), but once it has already occurred, the key question is whether it is possible to save neurons. Purpose The aim of this study was to determine if a purified alkaloid extract (AE) obtained from Phlegmariurus saururus, a genus of Lycophyte plants (sometimes known as firmossesor fir club mosses) could induce neuroprotection following SE. Methods In vitro and in vivo techniques were applied for this purpose. Protein levels were measured by western blotting procedures. Neuronal death analysis was performed by calcein-ethidium staining and the presence of the NeuN protein as a marker for presence or absence of cells (in vitro experiments) and by Fluoro Jade B staining for the in vivo experiments. Results The effect of AE in the hippocampal neurons culture was the first determination, where we found an increase in neuronal survival and in the level of pErk and TrkB activation, 24 h after the addition of AE. In a well-established in vitro model of SE, we found that 24 h after being added to the hippocampal neuron-astrocyte co-culture, the AE induces a significant increase in neuronal survival. In addition to this, in the in vivo Li-pilocarpine model of SE, the AE induced a remarkable neuroprotection in areas such as the entorhinal cortex and hippocampal CA1 area. Conclusion These results make the AE an excellent candidate for potential clinical use in neurological disorders where memory impairment and neuronal death occurs.Fil: Danelon, Víctor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Montroull, Laura Ester. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; ArgentinaFil: Vallejo, Mariana Guadalupe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Cabrera, Jose Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Agnese, Alicia Mariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Ortega, María Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Masco, Daniel Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Biológicas y Tecnológicas. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Investigaciones Biológicas y Tecnológicas; Argentin