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1.
Trop Anim Health Prod ; 53(2): 256, 2021 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-33839954

RESUMEN

Small-scale dairy systems (SSDS) are important source of livelihood and socio-economic wellbeing for the rearers in general. The reduction of methane emissions with the inclusion of sunflower seed or seed-meal in rations for dairy cows has been reported in several studies. However, studies pertaining to the use of sunflower silage in dairy cattle feeding are lacking. The present study was conducted to assess the productive, economic, and environmental effects of the inclusion of graded levels of sunflower silage at 0%, 20%, 40%, and 60% (SFSL) along with maize silage (MZSL) on a dry matter basis. The silage was provided to eight Holstein cows in two 4×4 Latin-squares with 14-day periods. The study encompassed the productive performance of the cows, composition of feeds, besides the feeding costs, and enteric methane emissions estimated. The study indicated that inclusion of SFSL in the diet enhanced (P<0.001) the FCM by 3.5% and milk-fat content. SFSL increased feeding costs, but income/feeding costs ratios did not differ across the treatments. The higher inclusion of SFSL reduced methane emissions/kg of DM intake, / kg of milk, and in energy lost as methane. The inclusion of sunflower silage in feeding strategies for cows may be a viable alternative by increasing their milk yields and milk fat content and reducing methane emissions without affecting the income/feeding costs ratios.


Asunto(s)
Bovinos/fisiología , Helianthus , Ensilaje , Animales , Dieta/veterinaria , Femenino , Lactancia , Metano/metabolismo , México , Leche , Rumen , Ensilaje/análisis , Ensilaje/economía , Zea mays
2.
J Dairy Sci ; 103(4): 3804-3815, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32037178

RESUMEN

Dairy farms have been under pressure to reduce negative environmental impacts while remaining profitable during times with volatile milk and commodity prices. Double cropping has been promoted to reduce negative environmental impacts and increase total dry matter yield per hectare. Three dairy farms that double cropped winter annuals and corn were selected from northern and western Pennsylvania. Data were collected from recorded crop and dairy records and financial data for 2016 and 2017. Farms ranged in size from 336 to 511 ha with 233 to 663 cows. Data were used to set parameters for the Integrated Farm System Model, which was then used to simulate 8 scenarios for each farm: current operation; 0, 50, and 100% of corn hectares double cropped; 30% feed price increase with and without double cropping; and 30% feed price decrease with and without double cropping at the farm's current level of double cropping. A 20-yr time period, using weather data that was representative of the actual farms, was used in the Integrated Farm System Model simulation to produce both financial and environmental outputs. Double cropping winter annuals and corn silage increased dry matter yield per hectare by 19%, when comparing 0 to 100% of the corn area double cropped. With all corn land double cropped, net return to management per hundredweight (45.36 kg) of milk increased by 1.8%, N leached per hectare per year decreased by an average of 4.5%, and phosphorus loss was reduced by an average of 9.2% across farms. When feed prices increased by 30%, double cropping increased net return over feed cost and net return to management by 1.6 and 2.2%, respectively, across farms. When feed prices decreased by 30%, double cropping decreased net return over feed cost and net return to management by smaller amounts of 0.13% and 0.11%, respectively, across farms. Modeling indicated that double cropping winter annuals with corn silage can have both environmental and economic benefits when winter-annual silage yields are enough to cover expenses.


Asunto(s)
Agricultura/métodos , Alimentación Animal/economía , Bovinos/fisiología , Ambiente , Granjas/economía , Zea mays/crecimiento & desarrollo , Agricultura/economía , Animales , Industria Lechera/economía , Femenino , Lactancia/fisiología , Leche/economía , Leche/metabolismo , Modelos Biológicos , Pennsylvania , Fósforo , Estaciones del Año , Ensilaje/economía
3.
J Dairy Sci ; 99(1): 634-43, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26506548

RESUMEN

Heifer rearing is one of the largest production expenses for dairy cattle operations, which is one reason milking operations outsource heifer rearing to custom developers. The cost of harvested feedstuffs is a major expense in heifer rearing. A possible way to lower feed costs is to graze dairy heifers, but little research exists on this topic in the mid-south United States. The objectives of this research were to determine the cost of feeding bred dairy heifers grazing native warm-season grasses (NWSG), with and without legumes, and compare the cost of grazing with the cost of rearing heifers using 3 traditional rations. The 3 rations were corn silage with soybean meal, corn silage with dry distillers grain, and a wet distillers grain-based ration. Bred Holstein heifers between 15- and 20-mo-old continuously grazed switchgrass (SG), SG with red clover (SG+RC), a big bluestem and Indiangrass mixture (BBIG), and BBIG with red clover (BBIG+RC) in Tennessee during the summer months. Total grazing days were calculated for each NWSG to determine the average cost/animal per grazing day. The average daily gain (ADG) was calculated for each NWSG to develop 3 harvested feed rations that would result in the same ADG over the same number of grazing day as each NWSG treatment. The average cost/animal per grazing day was lowest for SG ($0.48/animal/grazing d) and highest for BBIG+RC ($1.10/animal/grazing d). For both BBIG and SG, legumes increased the average cost/animal per grazing day because grazing days did not increase enough to account for the additional cost of the legumes. No difference was observed in ADG for heifers grazing BBIG (0.85 kg/d) and BBIG+RC (0.94 kg/d), and no difference was observed in ADG for heifers grazing SG (0.71 kg/d) and SG+RC (0.70 kg/d). However, the ADG for heifers grazing SG and SG+RC was lower than the ADG for heifers grazing either BBIG or BBIG+RC. The average cost/animal per grazing day was lower for all NWSG treatments than the average cost/animal per day for all comparable feed rations at a low, average, and high yardage fee. Results of this study suggest that SG was the most cost-effective NWSG alternative to harvested feeds for bred dairy heifer rearing.


Asunto(s)
Bovinos/fisiología , Industria Lechera/economía , Ensilaje/economía , Animales , Cruzamiento , Costos y Análisis de Costo , Fabaceae , Femenino , Panicum , Tennessee , Trifolium , Zea mays
4.
J Sci Food Agric ; 96(13): 4584-93, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26909546

RESUMEN

BACKGROUND: Intensive grazing by cattle on wet pasture can have a negative effect on soil physical quality and future pasture production. On a North Otago dairy farm in New Zealand, experimental plots were monitored for four years to assess whether preventing cow grazing of wet pastures during the milking season would improve soil structure and pasture production compared with unrestricted access to pastures. The DairyNZ Whole Farm Model was used to scale up results to a farm system level and ascertain the cost benefit of deferred grazing management. RESULTS: Soils under deferred grazing management had significantly higher total porosity, yet no significant improvement in macroporosity (values ranging between 0.112 and 0.146 m(3) m(-3) ). Annual pasture production did not differ between the control and deferred grazing treatments, averaging 17.0 ± 3.8 and 17.9 ± 4.1 t DM ha(-1) year(-1) respectively (P > 0.05). Furthermore, whole farm modelling indicated that farm operating profit was reduced by NZ$1683 ha(-1) year(-1) (four-year average) under deferred grazing management. CONCLUSION: Deferring dairy cow grazing from wet Pallic soils in North Otago was effective in improving soil structure (measured as total soil porosity), yet did not lead to a significant increase in pasture production. Whole farm modelling indicated no economic benefit of removing cows from wet soils during the milking season. © 2016 Society of Chemical Industry.


Asunto(s)
Industria Lechera/métodos , Herbivoria , Leche/metabolismo , Modelos Económicos , Ensilaje , Suelo/química , Agua/análisis , Alimentación Animal/economía , Animales , Bovinos , Conservación de los Recursos Naturales/economía , Análisis Costo-Beneficio , Costos y Análisis de Costo , Industria Lechera/economía , Femenino , Lactancia , Leche/economía , Nueva Zelanda , Porosidad , Estaciones del Año , Ensilaje/economía
5.
Commun Agric Appl Biol Sci ; 80(1): 23-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26630751

RESUMEN

Recently, biogas plant managers in Flanders face increased financial uncertainty. Between 2011 and 2012, 20% of the Flemish biogas plants went bankrupt. Difficulties in obtaining feedstock at stable and affordable prices is one reason why the biogas sector struggles. In literature, contracting is often proposed as a way to decrease the volatility of the feedstock costs. However, these studies generally do not consider the context in which the biogas plant manager needs to buy the feedstock. Yet, this context could be of specific importance when biogas plant managers are in competition with other users of the same biomass type. Silage maize is an example of such a feedstock, as it is both used by dairy farmers and biogas plant managers. Using a combination of qualitative research and agent-based modelling, we investigated the effect of specific characteristics of the silage maize market on the acquisition of local silage maize by biogas plant managers. This paper details the institutional arrangements of the silage maize market in Flanders and the results of a scenario analysis, simulating three different scenarios. As shown by the results, the time of entry into the market, as well as the different institutional arrangements used by the biogas plant managers as opposed to dairy farmers could explain the difficulties in obtaining a stable supply of local silage maize by biogas plants. Our findings can help to develop mitigation strategies addressing these difficulties.


Asunto(s)
Biocombustibles/economía , Reactores Biológicos , Modelos Teóricos , Ensilaje/economía , Zea mays , Bélgica
6.
J Sci Food Agric ; 92(3): 481-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21987231

RESUMEN

BACKGROUND: The concept of a designer biochar that targets the improvement of a specific soil property imposes the need for production processes to generate biochars with both high consistency and quality. These important production parameters can be affected by variations in process temperature that must be taken into account when controlling the pyrolysis of agricultural residues such as manures and other feedstocks. RESULTS: A novel stochastic state-space temperature regulator was developed to accurately match biochar batch production to a defined temperature input schedule. This was accomplished by describing the system's state-space with five temperature variables--four directly measured and one change in temperature. Relationships were derived between the observed state and the desired, controlled state. When testing the unit at two different temperatures, the actual pyrolytic temperature was within 3 °C of the control with no overshoot. CONCLUSION: This state-space regulator simultaneously controlled the indirect heat source and sample temperature by employing difficult-to-measure variables such as temperature stability in the description of the pyrolysis system's state-space. These attributes make a state-space controller an optimum control scheme for the production of a predictable, repeatable designer biochar.


Asunto(s)
Carbón Orgánico/química , Fertilizantes/análisis , Modelos Químicos , Algoritmos , Alimentación Animal/análisis , Alimentación Animal/economía , Crianza de Animales Domésticos/economía , Carbón Orgánico/análisis , Carbón Orgánico/economía , Fenómenos Químicos , Simulación por Computador , Fertilizantes/economía , Calefacción/instrumentación , Calor , Residuos Industriales/análisis , Residuos Industriales/economía , Cinética , Estiércol/análisis , Nitrógeno/química , Control de Calidad , Reproducibilidad de los Resultados , Ensilaje/análisis , Ensilaje/economía , Procesos Estocásticos , Estados Unidos
7.
J Dairy Sci ; 94(6): 3184-201, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21605788

RESUMEN

The objective of these experiments was to compare 4 total mixed rations fed to USDA-certified organic dairy cows in New England. Forty-eight Jersey cows from the University of New Hampshire (UNH) and 64 Holstein cows from the University of Maine (UMaine) were assigned to a 2 × 2 factorial arrangement of treatments testing the main effects of corn silage versus grass silage as the forage base and commodity concentrates versus a complete pelleted concentrate mixture. Treatment diets were fed as a total mixed ration for 8 wk during the winter and spring months of 2007, 2008, and 2009. Milk yield, component, and quality data were recorded and used to calculate the value of the milk produced for each cow. The dry matter intake (DMI) was recorded and used to calculate the average cost per cow per day of each diet. Income over feed costs were calculated for each diet using milk value and feed cost data. Feed cost and income over feed cost data were resampled using bootstrap methodology to examine potential patterns. Milk yield, milk fat and true protein concentrations, and SCC were similar among treatments. Cows at UNH fed corn silage tended to have higher DMI and lower milk urea nitrogen than did cows fed grass silage, whereas cows fed pellets had higher DMI than cows fed commodities. Cows at UNH fed commodities tended to have higher body condition scores than those fed pellets. Cows at UMaine fed commodities tended to have higher DMI than did cows fed pellets, and cows fed corn silage had lower milk urea nitrogen than did cows fed grass silage. Body weights and body condition scores were not different for cows at UMaine. Feed costs were significantly higher for corn silage diets and diets at UNH containing pellets, but not at UMaine. The calculated value of the milk and income over feed costs did not differ among treatments at either university. Bootstrap replications indicated that the corn silage with commodities diet generally had the highest feed cost at both UNH and UMaine, whereas grass silage diets containing commodities generally had the lowest cost. In contrast, the grass silage with commodities diets had the highest income over feed cost in the majority of the replications at both UNH and UMaine replications, whereas the corn silage with commodities diets had the lowest rank. Similar results were observed when forage prices were increased or decreased by 5, 10, and 25% above or below the actual feed price. Feeding a grass silage-based diet supplemented with commodity concentrates may have an economic advantage for dairy producers in New England operating under an organic system of production.


Asunto(s)
Industria Lechera/economía , Industria Lechera/métodos , Dieta/veterinaria , Leche/economía , Ensilaje/economía , Animales , Bovinos , Dieta/economía , Grasas de la Dieta/análisis , Suplementos Dietéticos/economía , Ingestión de Alimentos , Femenino , Lactancia , Maine , Leche/química , Leche/citología , Leche/metabolismo , Proteínas de la Leche/análisis , New England , New Hampshire , Poaceae , Estaciones del Año , Zea mays/economía
8.
Trop Anim Health Prod ; 43(5): 947-54, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21327716

RESUMEN

The objective was to determine the effect of including silages of annual ryegrass (Lolium multiflorum) intercropped with winter vetch (Vicia villosa) (ARG-VV) or with common vetch (Vicia sativa) (ARG-VS) compared with maize silage (MS) on milk yield and milk composition of dairy cows grazing cultivated perennial ryegrass-white clover pastures with supplemented concentrate during the dry season. Six Holstein dairy cows with a mean yield of 19.0 kg/cow/day at the beginning of the experiment were randomly assigned to a 3 × 3 repeated Latin square. Treatments were: 8 h/day intensive grazing, 3.6 kg of dry matter (DM) per cow per day of concentrate plus MS, and ARG-VV or ARG-VS ad libitum at a stocking rate of 3.0 cows/ha for three experimental periods of 3 weeks each. Milk yield (MY) and milk composition, live weight and body condition score as well as silage and concentrate intakes were recorded during the third week of each experimental period, and pasture intake was estimated indirectly from utilised metabolisable energy. Economic analysis was obtained by preparing partial budgets. There were no statistical differences (P > 0.10) in MY, milk fat or protein content nor for live weight, but there was significant difference (P < 0.10) in body condition score. There were non-statistical differences in silage DM intake (P < 0.11); however, significant differences (P < 0.10) were obtained for estimated grazed herbage intake whilst no differences for total DM intake. Slightly higher economic returns (10%) were obtained with ARG-VS over MS, and this was 7% higher than ARG-VV. It is concluded that ARG-VS could be an option for complementing grazing for small-scale dairy production systems in the dry season as it is comparable to MS in animal performance and slightly better in economic terms.


Asunto(s)
Bovinos/fisiología , Industria Lechera/métodos , Dieta/veterinaria , Leche/química , Ensilaje/análisis , Crianza de Animales Domésticos , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Industria Lechera/economía , Femenino , Lactancia , Lolium/química , México , Leche/metabolismo , Distribución Aleatoria , Ensilaje/economía , Vicia/química , Vicia sativa/química , Zea mays/química
9.
Trop Anim Health Prod ; 42(5): 1027-9, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20043240

RESUMEN

Silage, which is anaerobically fermented green fodder, is valued throughout the world as a source of animal feed during lean months. Several farms in India use carbohydrate sources like jaggery or molasses at 2% for preparation of silage, and this increases cost of production. The present study was undertaken to assess the effect of jaggery on quality and intake of maize silage, with an objective to find out whether additional carbohydrate source is essential in preparation of silage using green maize. Three silage types, one without jaggery (A), the second with 1% jaggery (B), and the third with 2% jaggery (C) were prepared in cylindrical bins under similar conditions. They were compared for colour, pH, lactic acid bacteria count, lactic acid content, proximate composition and silage intake by sheep. Silage type C with 2% jaggery was significantly different from the other two types with values of 3.98 and 805.66 g for pH and mean silage intake, respectively. Even though the values of pH and dry matter intake for all three silage types were within normal levels, silage type C was significantly superior in terms of fermentation and palatability. The method of preparation followed could be ideal for small holder farmers requiring less quantity of silage.


Asunto(s)
Ingestión de Alimentos , Extractos Vegetales/farmacología , Ovinos/fisiología , Ensilaje/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Ácido Láctico/química , Lactobacillus , Extractos Vegetales/química , Extractos Vegetales/economía , Ensilaje/economía , Zea mays
10.
Anim Sci J ; 88(1): 99-106, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27147561

RESUMEN

To improve the silage quality and reduce the silage additive cost, the present experiment was designed to evaluate the potential of applying the fermented juice of epiphytic lactic acid bacteria (FJLB) as an additive in alfalfa silage. The effects of FJLB on the fermentation quality, carbohydrate and protein fractions, and aerobic stability of alfalfa silage wilted under five different conditions were investigated and compared with commercial lactic acid bacteria (CLAB) and the control. The FJLB application decreased the pH value, the volatile fatty acids and non-protein nitrogen content, and the loss of sugar by 9.9%, 22.9%, 19.6% and 9.6%, respectively; it increased the lactic acid concentration by 29.5% and the aerobic stability by 17 h in comparison to the control. The FJLB application also decreased the pH value (4.44 vs. 4.66) and volatile fatty acid content (38.32 vs. 44.82) and increased the lactic acid concentration (68.99 vs. 63.29) in comparison to the CLAB-treated silage. However, the FJLB treatment had lower aerobic stability (254 h vs. 274 h) than the CLAB treatment. The FJLB application improved silage quality in comparison to the control; in addition, its effect as a fermentation stimulant may be comparable to or even better than CLAB.


Asunto(s)
Carbohidratos de la Dieta/análisis , Proteínas en la Dieta/análisis , Aditivos Alimentarios/economía , Calidad de los Alimentos , Lactobacillus , Medicago sativa , Ensilaje/análisis , Ensilaje/economía , Aerobiosis , Ácidos Grasos Volátiles/análisis , Fermentación , Concentración de Iones de Hidrógeno , Ácido Láctico/análisis
11.
Bioresour Technol ; 76(3): 207-12, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11198171

RESUMEN

A crude enzyme preparation, obtained by solid substrate fermentation (SSF) with a Gliocladium spp. and added at the 5% level to wilted or non-wilted alfalfa, improved the fermentation characteristics and stability of alfalfa silages as effectively as commercial preparations, Novo-Nordisk Celluclast 1.5 L and Viscozyme 120 L, applied at the 0.025% level. The effective dose of the crude enzyme costs about one-fourth of the cost of the commercial enzymes.


Asunto(s)
Gliocladium/enzimología , Gliocladium/metabolismo , Medicago sativa/metabolismo , Ensilaje , Metabolismo de los Hidratos de Carbono , Fibras de la Dieta/metabolismo , Fermentación , Ácido Láctico/metabolismo , Medicago sativa/microbiología , Ensilaje/economía , Ensilaje/microbiología
12.
J Anim Sci ; 56(3): 525-8, 1983 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-6682420

RESUMEN

Source of supplemental N was evaluated in three corn silage-based complete mixed diets (CMD) fed to lactating dairy cows. Diets were formulated to be isonitrogenous and contained 60% corn silage and 40% concentrate on a dry matter basis. Diets were: CMD-A, ammoniated corn silage (ammonia provided 16% of total N) plus concentrate; CMD-U, untreated corn silage and concentrate (16% of total N from urea) and CMD-S, untreated corn silage plus concentrate with soybean meal. Ammoniation at 1.0% of dry weight increased crude protein content of silage from 8.5 to 12.7%. Daily means for cows fed CMD-A, CMD-U and CMD-S were: 24.2, 24.3 and 24.5 kg of fat-corrected milk; 3.17, 3.10 and 3.15% milk protein; 3.41, 3.67 and 3.63% milk fat and 3.02, 2.99 and 3.02 kg intake of total dry matter/100 kg body weight. Differences were not significant except for reduced milk fat percentage for cows fed the ammoniated corn silage diet. Both anhydrous ammonia and urea at 16% of total dietary N were found to be practical and economical substitutes for part of the supplemental soy protein. When compared to CMD with all soybean protein, greater savings in feed costs resulted from inclusion of ammoniated corn silage than with inclusion of urea.


Asunto(s)
Amoníaco/administración & dosificación , Alimentación Animal , Bovinos/metabolismo , Ensilaje , Urea/administración & dosificación , Zea mays , Alimentación Animal/economía , Animales , Femenino , Lactancia , Leche/metabolismo , Embarazo , Ensilaje/economía
13.
J Anim Sci ; 72(7): 1849-56, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7928765

RESUMEN

Sixty Romanov x Dorset (RVDP) and sixty Romanov x Suffolk (RVSU) male lambs were used in a 2 x 5 factorial arrangement of treatments including two breed crosses and five diets to determine the effect of breed crosses on performance and to compare growth and carcass characteristics of lambs. Diets consisted of an all-silage diet, silage supplemented with 100 g of fish meal.animal-1.d-1, or silage supplemented daily with concentrate at either 200 g or 400 g per animal, or ad libitum intake. Lambs were fed from an initial weight of 23 kg to a slaughter weight of 45 kg. There was no interaction (P > .10) between diet and breed for any parameter measured. Silage DMI was decreased (P < .05) by supplementation, but total DMI was similar among diets. The ADG was increased by fish meal and concentrate supplementation, with higher (P < .05) ADG observed with ad libitum access to concentrate. Lambs that had ad libitum access to concentrate had an improved gain:feed and required less time to reach market weight but had more carcass fat than lambs fed other diets. Lambs fed only silage had a higher percentage of carcass with poorer muscling than others. The highest percentage of carcasses with excellent to good muscling, normal fat covering, and grades A1 and A2 was obtained with fish meal supplementation. Lambs from the RVSU-crossbreed had better ADG than RVDP lambs but carcass quality of RVDP lambs was better than that of RVSU lambs.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Cruzamientos Genéticos , Productos Pesqueros , Carne/normas , Ovinos/crecimiento & desarrollo , Ensilaje , Tejido Adiposo/crecimiento & desarrollo , Animales , Costos y Análisis de Costo , Dieta , Ingestión de Alimentos , Alimentos Fortificados/economía , Análisis de los Mínimos Cuadrados , Masculino , Desarrollo de Músculos , Músculo Esquelético/crecimiento & desarrollo , Distribución Aleatoria , Ovinos/genética , Ensilaje/economía , Aumento de Peso
14.
Bioresour Technol ; 102(2): 2086-92, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20801018

RESUMEN

Landscape management grass is generally harvested late, resulting in unfavorable composition for many utilization purposes. This study explores various technical concepts of biogas production and their economic viability. The Lower Oder Valley National Park is taken here as an example. This National Park in North-East Germany comprises large grassland areas with conservation-related restrictions on management. The concepts of biogas production and use considered are: (1) decentralized digestion and use of biogas at five autonomous combined heat and power (CHP) units, (2) decentralized digestion and delivery of the biogas to a centralized CHP unit, (3) decentralized digestion, upgrading of the biogas and feeding into the natural gas grid, and (4) one central biogas plant with centralized CHP unit. Annual costs and revenues of biogas production were calculated for each alternative. Biogas production from landscape management grass meets the conservational demands of late cutting periods and under certain circumstances shows a profit.


Asunto(s)
Biocombustibles/análisis , Biocombustibles/economía , Biotecnología/economía , Biotecnología/métodos , Poaceae/metabolismo , Alemania Oriental , Metano/análisis , Ensilaje/economía , Transportes/economía
15.
Bioresour Technol ; 100(4): 1595-607, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18951018

RESUMEN

Sweet sorghum has been identified as a possible ethanol feedstock because of its biomass yield and high concentration of readily fermentable sugars. It has found limited use, however, because of poor post-harvest storage characteristics and short harvest window in cooler climates. Previous research (Bennett, A.S., Anex, R.P., 2008. Farm-gate production costs of sweet sorghum as a bioethanol feedstock. Transactions of the ASABE 51(2), 603-613) indicates that fermentable carbohydrates (FC) can be produced at less expense from sweet sorghum than from corn grain. Previous research, however, did not include costs associated with off-farm transportation, storage, or capital costs associated with milling and energy recovery equipment that are required to provide FC suitable for biological conversion. This study includes these additional costs and reevaluates sweet sorghum as a biocommodity feedstock. A total of eight harvest-transport-processing options are modeled, including 4-row self-propelled and 2-row tractor-pulled forage harvesters, two different modes of in-field transport, fresh processing, on-farm ensilage and at-plant ensilage. Monte Carlo simulation and sensitivity analysis are used to account for system variability and compare scenarios. Transportation costs are found to be significant ranging from $33 to $71 Mg (-1) FC, with highest costs associated with at-plant ensilage scenarios. Economies of scale benefit larger milling equipment and boiler systems reducing FC costs by more than 50% when increasing annual plant capacity from 37.9 to 379 million liters. Ensiled storage of high moisture sweet sorghum in bunkers can lead to significant losses of FC (>20%) and result in systems with net FC costs well above those of corn-derived FC. Despite relatively high transport costs, seasonal, fresh processed sweet sorghum is found to produce FC at costs competitive with corn grain derived FC.


Asunto(s)
Agricultura/economía , Agricultura/métodos , Fuentes de Energía Bioeléctrica/economía , Etanol/síntesis química , Etanol/economía , Sorghum/metabolismo , Transportes/economía , Carbohidratos/química , Simulación por Computador , Fermentación , Medio Oeste de Estados Unidos , Método de Montecarlo , Ensilaje/economía
16.
J Dairy Sci ; 75(6): 1507-16, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1323581

RESUMEN

A net carbohydrate and protein system was used to develop model diets for lactating dairy cattle with various protein solubilities in the alfalfa silage component of the diet. The objective was to determine the level to which alfalfa silage could be used to replace supplemental protein sources as the silage protein solubility decreased and to estimate the value of silage treatments needed to reduce protein solubility. Four cow groups were considered: early lactation multiparous cows, primiparous cows, midlactation cows, and late lactation cows. Diets were balanced for metabolizable protein, metabolizable energy, and ammonia and peptides for rumen bacteria; limits on DMI and effective NDF were enforced. Lower protein solubility was predicted to increase the yield of bacteria per unit of alfalfa silage DM and the yield of metabolizable protein per unit of alfalfa silage CP. Because of reduced protein supplements, diet costs were decreased. The savings per unit of silage in these rations increased as alfalfa silage protein solubility decreased. For example, with a reduction in solubility from 61 to 51% of CP, the savings ranged from $2.96 to $3.26/tonne of silage across the four cow groups. The value of acid treatment of silage needed to effect these reductions exhibited diminishing returns as application rate increased and appeared to be most cost effective when used on high quality alfalfa fed to high producing cows with application rates less than 2 kg/tonne. Management practices that reduce silage temperatures were predicted to save $.50 to $1.50/tonne of silage when the diets were balanced to account for protein degradability.


Asunto(s)
Bovinos/fisiología , Proteínas en la Dieta/metabolismo , Lactancia/fisiología , Rumen/fisiología , Ensilaje , Animales , Bacterias/metabolismo , Análisis Costo-Beneficio , Costos y Análisis de Costo , Fibras de la Dieta/administración & dosificación , Digestión , Femenino , Fermentación , Manipulación de Alimentos/economía , Medicago sativa , Rumen/microbiología , Ensilaje/economía , Solubilidad
17.
J Dairy Sci ; 84(1): 177-82, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11210031

RESUMEN

A 2-yr study was conducted to determine the chemical composition and digestibility of silages made from forage sorghum, pearl millet, and tropical corn managed to optimize forage quality. Silages were ensiled in upright concrete silos lined with plastic and fed to heifers to determine in vivo apparent digestibility. Samples were collected before and after ensiling to determine ensiling characteristics and forage quality. After ensiling, tropical corn had the greatest dry matter (DM), the lowest crude protein, and the greatest water-soluble concentrations. Tropical corn silage had a pH of 3.96. The pH of forage sorghum silage was 4.09, and pearl millet had a pH of 4.50. Pearl millet had the lowest concentration of preensiled water-soluble carbohydrate, which likely caused the high pH in the silage. There were no differences among the forages in DM loss during ensiling in yr 2. Heifers fed pearl millet silage consumed more DM, but digestible DM intake was not different among the three groups of heifers. The results of this experiment indicate that pearl millet would be less desirable as a crop intended solely for silage production. Both forage sorghum and tropical corn could be grown specifically for ensiling based on DM digestibility. The decision on which crop to use should be based on factors such as production costs, forage yields, and local growing conditions rather than silage quality.


Asunto(s)
Alimentación Animal , Bovinos/fisiología , Digestión , Ingestión de Alimentos , Ensilaje/análisis , Animales , Femenino , Manipulación de Alimentos , Concentración de Iones de Hidrógeno , Lolium , Panicum , Proteínas , Estaciones del Año , Ensilaje/economía , Solubilidad , Zea mays
18.
Crit Rev Food Sci Nutr ; 16(4): 383-419, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-7047081

RESUMEN

Based on a review of various production principles of fish silage, this paper discusses the prospects of introduction of this method, as an alternative to fish meal, to utilize low value fish and waste products, particularly in developing countries. The paper covers the biochemistry, microbiology, and nutritional aspects of fish silage, as well as production technology and economy.


Asunto(s)
Alimentación Animal , Productos Pesqueros , Productos Pesqueros/efectos adversos , Tecnología de Alimentos/métodos , Ensilaje , Alimentación Animal/normas , Animales , Fermentación , Productos Pesqueros/análisis , Productos Pesqueros/economía , Peces , Microbiología de Alimentos , Conservación de Alimentos/normas , Concentración de Iones de Hidrógeno , Valor Nutritivo , Aves de Corral , Ensilaje/análisis , Ensilaje/economía , Ensilaje/normas , Porcinos
20.
Braz. j. vet. res. anim. sci ; 32(4): 224-8, 1995. tab
Artículo en Portugués | LILACS | ID: lil-240104

RESUMEN

Doze vacas das raças Holandesas e Pardo Suíço produzindo 23 kg/dia em média foram utilizadas em delineamento tipo "switch-back" para avaliar os seguintes volumosos fornecidos à vontade e com quantidades fixas de farelo de soja ajustados para atender mantença mais produçäo diária dos primeiros 8 kg de leite: A) silagem de milho + 1,50 kg de farelo de soja; B) 50 por cento de silagem de milho + 50 por cento de cana-de-açúcar + 2,25 kg de farelo de soja; C) cana-de-açúcar + 3,00 kg de farelo de soja. As médias diárias de produçäo de leite, corrigidas à matéria graxa nos tratamentos foram: A = 19,63 kg e 3,57 por cento, B) 18,94 kg e 3,50 por cento, C) 18,07 kg e 3,46 por cento, respectivamente, e näo apresentaram diferenças significativas (P>0,05). O consumo da matéria seca e de nutrientes digestíveis totais pelos animais diminuíram com o aumento de cana-de-açúcar nas dietas e atendidas as exigências das vacas em termos de MS, PB e NDT, foi possível substituir a silagem de milho por cana-de-açúcar, garantindo-se produçöes de leite semelhantes, em torno de 18,0 kg/animal/dia


Asunto(s)
Animales , Femenino , Bovinos , Leche/economía , Alimentación Animal/economía , Ensilaje/economía , Glycine max , Zea mays/economía
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