\u3ci\u3eIn Vitro\u3c/i\u3e Gas Production Technique to Predict DMD of Ensiled Forage Ruminant Based Diets

The in vitro gas production technique was used as a tool to develop an improved prediction model of dry matter digestibility of ensiled forage based diets. Eleven diets were tested through conventional experiments of in vivo dry matter digestibility (DMD). The same diets were evaluated by the in vitro gas production technique using a gas pressure transducer . The parameters of the model y = A - B Qt Z√t were calculated with data from the accumulated gas curves, i.e. y=cumulative gas production (ml), Q=e-b, Z=e-c, B=ebT+c√T , being A the value for gas pool size (ml), plus lag time, minimum lag time, time for 50% gas production and time for 95% gas production. A stepwise linear regression procedure was used to obtain a model with the best fit. The higher adjusted R2 (0.85) was obtained for a model with: 1. accumulated gas, 2. lag time, 3. Q, 4. B, 5. time for 50% gas production and 6. minimum lag time were included in the model

Performance of Dairy Goats to Alfalfa Silage Based Diets Supplemented with Different Sources of Carbohydrates

Lactating Saanen dairy goats fed alfalfa silage (AS) based diets in four 4x4 Latin Square designed experiment were studied for the effects of supplementation of three different type of carbohydrates (wheat grain, (W); sorghum grain, (SG) and dry citrus pulp, (DCP)) on milk yield, composition and chewing activities. Sixteen does (45± 10 DIM and 2.016 kg ± 0.48 4% FCM) housed indoors in individual pens in a four 4x4 experiment were fed four diets 1) AS (33.9%DM, 19.9%CP, 44.01%NDF); 2) ASW (52.4%DM, 19.8%CP, 33.7%NDF); 3) ASSG (50.9%DM, 17.9%CP, 37%NDF), 4) ASDCP (52.5%DM, 16.12%CP, 39.1%NDF) with forage-to-concentrate ratios of 100:0 or 65:35, 67:33 and 64:36 respectively. Intake of AS DM (2.78%BW) was different (P\u3c 0.05) from the other treatments (average 3.53 ±0.07 %BW). Chewing efficiency (min/g NDF per kg BW 0.75) decrease (P\u3c 0.05) as a result of AS substitution or concentrate supplementation without effect (P\u3e 0.05) of carbohydrate type or dietary level of NDF. Milk, 4%FCM and fat-protein-corrected milk yield was affected (P\u3c 0.05) by concentrate supplementation. Either milk protein content (g/l) or yield (g/day) were not affected by treatments. Body weight changes appeared related to concentrate supplementation. Supplementation increase total DM intake, decrease forage DM intake and chewing efficiency and increase producing performance without changing milk composition

Effect of condensed tannins in the methanogenic potential and in vitro digestion efficiency of ryegrass

Los rumiantes son capaces de degradar y fermentar los componentes de la pared celular de forrajeras. En el retículo-rumen, la fermentación microbiana particiona la energía bruta del sustrato en ácidos grasos volátiles, biomasa microbiana (BM) y gases de desecho (e.g. metano, CH4). Estos últimos son eliminados y representan, no solo contaminación ambiental por su efecto invernadero; sino también una pérdida de la energía disponible en el alimento. Numerosas especies vegetales poseen metabolitos secundarios, tales como los taninos condensados (TC), que, aunque tienen propiedades antimicrobianas y astringentes, su uso racional podría generar un mejor aprovechamiento de los forrajes con potenciales efectos mitigadores del CH4 entérico. En este contexto, se evaluó el efecto de cuatro dosis de TC de Quebracho (Schinopsis balansae, 0, 1,5, 3,0 y 4,5 mg TC cada 100 mg de sustrato; correspondientes a los tratamientos Ctrl, TC1, TC2 y TC3) mediante la técnica de producción de gas in vitro (PGiv), en presencia o ausencia de polietilenglicol (inhibidor específico de los TC), para determinar el impacto en la fermentación ruminal del raigrás (Lolium perenne). La digestibilidad disminuyó en TC3, mientras que la PGiv aumentó asociada a las mayores tasas iniciales. No hubo efecto de los TC sobre la producción de CH4, tampoco en la síntesis de BM. Por otro lado, el agregado de TC disminuyó la concentración de ácido propiónico, aumentado la relación acético: propiónico. Se concluye que los TC de Quebracho a las dosis estudiadas, no produjeron un efecto mitigador del CH4, además de modificar los parámetros de fermentación, sobre todo con una inclusión de 4,5 mg de TC/100 mg de sustrato incubado.Ruminants are capable of degrading and fermenting the forage cell wall components. In reticulo-rumen, the microbial fermentation partition gross energy of the substrate into volatile fatty acids, microbial biomass (MB) and waste gases (e.g. methane, CH4). These gases are eliminated and they represent, not only environmental pollution due to its greenhouse effect, but they also represent loss of the energy available in the forage. Numerous plant species have secondary compounds, such as condensed tannins (CT), although they have antimicrobial and astringent properties, their rational use could generate a better use of forages with potential mitigating effects of enteric CH4. In this context, it was evaluated the effect of four doses of Quebracho (Schinopsis balansae, 0, 1.5, 3.0 and 4.5 mg of CT per 100 mg of substrate, correspond to treatments Ctrl, TC1, TC2 and TC3) using the in vitro gas production technique (ivGP), in the presence or absence of polyethylene glycol (specific inhibitor of CT), to determine the impact on ruminal fermentation of ryegrass (Lolium perenne). The digestibility decreased in TC3, while the ivGP increased asociated with the higher initial rates. There was no effect of the CT on the CH4 production, neither in the synthesis of MB. On the other hand, the addition of CT decreased propionic acid concentration, increasing the acetic: propionic ratio. It is concluded that the CT of Quebracho, at the doses studied, did not produce a CH4 mitigating effect, in addition to modifying the fermentation parameters, especially with an inclusion of 4.5 mg of CT/ 100 mg of incubated substrate.Fil: Cantet, Juan Manuel. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Neumann Reiter, A. M.. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal; ArgentinaFil: Colombatto, Dario. 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; ArgentinaFil: Wawrzkiewicz, Marisa. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal; ArgentinaFil: Jaurena, Gustavo. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal; Argentin

Comparison of Varion resins selectivity towards palladium(II) ions in hydrochloric acid solutions with sodium chloride addition

Ion exchange is Ion exchange is found more and more signifi cant importance in metal processing, and hydrometallurgy in general, not only for the removal of impurities but also for the reconcentration process of metal ions. The ion exchange method (dynamic method) was applied in the preconcentration of palladium(II) ions from the chloride solutions with sodium chloride addition. Varion resins such as the strongly basic anion exchange resins: Varion ADM and Varion ATM and the weakly basic anion exchange resin Varion ADAM were taken into account during the sorption process. The selectivity series were obtained based on the breakthrough curves of palladium(II) ions determined by means of dynamic method. Moreover, the distribution coefficients: weight and bed as well as the working anion exchange capacities were calculated. From the Varion resins — Varion ADAM is the most promising in the preconcentration of Pd(II)

Usuwanie toksycznych jonów metali ciężkich oraz metalobarwników z roztworów wodnych z wykorzystaniem jonitu oraz tlenku mineralnego

The aim of the study was to compare the removal efficiency of toxic heavy metal ions: chromium(VI), nickel(II) and copper(II) as well as metal-complex dyes from aqueous solution using Lewatite VPOC 1065 and AdsorbsiaTM As500. The point of zero charge (pHPZC) of both sorbents and the influence of the initial concentration on the sorption process of Ni(II), Cu(II), Cr(VI), C.I. Acid Red 183 (AR183), C.I. Reactive Blue 21 (RB21) and nickel(II) phthalocyanine-tetrasulfonic acid tetrasodium salt (NiPc-TSATSS) were studied to determine the maximum sorption capacity. Kinetic studies were also carried out for the most effective sorbent-sorbate systems. The concentration effect of both hydrochloric acid and auxiliaries on the removal yield was also taken into account. As was found, Lewatit VPOC 1065 can be successfully applied for the treatment of textile wastewaters containing metal complex dyes and heavy metal ions. The highest sorption capacity, qe = 816.1 mg/g, was found for C.I. Acid Red 183.Wśród zanieczyszczeń środowiska na szczególną uwagę zasługują metale ciężkie oraz metalobarwniki, które emitowane są do środowiska z różnych gałęzi przemysłu. Z uwagi na ich negatywny wpływ na organizmy żywe niezwykle istotnym jest ich usuwanie z wód i ścieków z wykorzystaniem różnych metod, wśród których adsorpcja odgrywa istotną rolę. Celem pracy było porównanie efektywności usuwania toksycznych jonów metali ciężkich: Cr(VI), Ni(II), Cu(II) oraz metalobarwników :C.I. Acid Red 183, C.I. Reactive Blue 21, soli tetrasodowej kompleksu nikluikwasu ftalocyjanino-tetrasulfonowego z roztworów wodnych z wykorzystaniem jonitu Lewatit VPOC 1065 oraz tlenku AdsorbsiaTM As500. Wyznaczono pHPZC obu sorbentów oraz zbadano wpływ stężenia początkowego na proces sorpcji badanych sorbatów oraz kinetykę procesu sorpcji dla najbardziej efektywnego układu sorbent-sorbat. W badaniach uwzględniono także wpływ stężenia kwasu chlorowodorowego oraz wpływ substancji pomocniczych na proces sorpcji