Corn Silage Ratio Research Articles

Feeding control of anaerobic co-digestion of waste activated sludge and corn silage performed by rule-based PID control with ADM1

Anaerobic co-digestion (AcoD) of corn silage (CS) and waste activated sludge (WAS) co-substrates, compared with anaerobic digestion (AD) of mono-substrate WAS, was simulated under mesophilic conditions with the adapted IWA Anaerobic Digestion Model No. 1 (ADM1), and a rule-based PID control system for control of the AcoD of CS and WAS, through control of their ratios in the feed, was developed, implemented with the model as a test platform. Tests on AcoD of co-substrates were conducted at the COD mass-based feeding ratios of CS to WAS 1:2.5, 1:2.0 and 1:1.2. The maximal biogas production was 0.94 m3/kgVS·d at the feeding ratio 1:1.2. The ADM1 was adapted, and the high-sensitivity kinetic parameters were calibrated and optimised using the data from the tests of steady state mono-digestion of WAS and AcoD of CS and WAS. The simulated data of biogas and methane production, methane content, VFA and pH agreed well with the test data. The rule-based PID control was developed with an additional expert system, in which the lower level controller operated the level of VFA/TIC and the upper level controller manipulated the setpoints of methane production. The feeding ratio of CS to WAS was used as a manipulated variable. With the constraint boundaries, the test on the control system showed that it could keep methane production stable to the setpoint and maximise methane production while resisting the disturbances to AcoD by adjusting the feeding ratios of CS to WAS.

Anaerobic digestion of cattle manure, corn silage and sugar beet pulp mixtures after thermal pretreatment and kinetic modeling study

In this study, biogas production was investigated from cattle manure (CM), corn silage (CS) and sugar beet pulp (SBP) mixtures under mesophilic conditions. In anaerobic digestion (AD), CM, CS and SBP were mixed in different ratios and the optimum mixture ratio was determined as 2:1:1, w/w/w respectively. In this mixture, biogas production was 180.5 mL/g TS. After the optimum mixing ratios of CM, CS and SBP were determined, thermal pretreatments were applied to this mixture ratio. Thermal pretreatments were performed at 100, 120, 150 and 180 °C with 10, 20, 30, 60 and 120 min for each temperature. Considering biogas production after thermal pretreatment, the best thermal pretreatment time was determined as 60 min for all pretreatment temperatures. The highest biogas yield was 362.1 mL/g TS in the reactor which is pretreated at 180 °C for 60 min. After thermal pretreatment at 180 °C for 60 min, the SCOD value in the reactor increased by 124.6% compared to the control. This reactor produced 100.6% higher biogas production compared to the control. In addition, the solubilization of cellulose, hemicellulose and lignin in this reactor was 38.2%, 32.9% and 23.2%, respectively. Cumulative biogas production (CBP) fitted to modified Gompertz and modified Bertalanffy models.

Performance, digestion, nitrogen balance, and emission of manure ammonia, enteric methane, and carbon dioxide in lactating cows fed diets with varying alfalfa silage-to-corn silage ratios

Two trials were conducted simultaneously to study the effects of varying alfalfa silage (AS) to corn silage (CS) ratio in diets formulated to avoid excess protein or starch on lactating dairy cow performance, digestibility, ruminal parameters, N balance, manure production and composition, and gaseous emissions [carbon dioxide (CO2), methane (CH4), and ammonia-N (NH3-N)]. In trial 1 all measurements, except gas emissions, were conducted on 8 rumen-cannulated cows in replicated 4×4 Latin squares. In trial 2, performance and emissions were measured on 16 cows randomly assigned to 1 of 4 air-flow controlled chambers in a 4×4 Latin square. Dietary treatments were fed as total mixed rations with forage-to-concentrate ratio of 55:45 [dietary dry matter (DM) basis] and AS:CS ratios of 20:80, 40:60, 60:40, and 80:20 (forage DM basis). Measurements were conducted the last 3d of each 21-d period. Treatments did not affect DM intake, DM digestibility, and milk/DM intake. However, responses were quadratic for fat-and-protein-corrected milk, fat, and protein production, which reached predicted maxima for AS:CS ratio of 50:50, 49:51, and 34:66, respectively. Nitrogen use efficiency (milk N/N intake) decreased from 31 to 24g/100g as AS:CS ratio increased from 20:80 to 80:20. Treatments did not alter NH3-N/milk-N but tended to have a quadratic effect on daily NH3-N emission. Treatments had a quadratic effect on daily CH4 emission, which was high compared with current literature; they influenced CH4 emission per unit of neutral detergent fiber (NDF) intake and tended to influence CO2/NDF intake. Ruminal acetate-to-propionate ratio and total-tract NDF digestibility increased linearly with increasing AS:CS ratio. In addition, as AS:CS ratio increased from 20:80 to 80:20, NDF digested increased linearly from 2.16 to 3.24kg/d, but CH4/digested NDF decreased linearly from 270 to 190g/kg. These 2 counterbalancing effects likely contributed to the observed quadratic response in daily CH4 emission, which may have been influenced also by increasing starch with increasing CS in the diet as reflected by the increased ruminal propionate molar proportion. Overall, production performances were greatest for the intermediate AS:CS ratios (40:60 and 60:40), but daily excretion of urine, manure, fecal N, urinary urea N, and urinary N decreased with increasing proportion of CS in the diet, whereas daily CH4 emission was reduced for the 2 extreme AS:CS ratios (20:80 and 80:20). However, the proportion of AS and CS in the diet did not affect CH4/fat-and-protein corrected milk.

Changes in Milk Production and Metabolic Parameters by Feeding Lactating Cows Based on Different Ratios of Corn Silage: Alfalfa Hay with Addition of Extruded Soybeans

The objective of this study was to investigate the effects of different ratios of corn silage (CS): alfalfa hay (AH), and extruded soybeans (ESB) on milk yield, milk composition, blood metabolites, and fatty acids in milk fat and plasma. Ninety multiparous Holstein cows were arranged in a randomized block design experiment which lasted 14 weeks. Treatments were arranged as a 3×3 factorial with 0%, 5% or 10% ESB (dry matter basis) and three forage treatments: i) 30% CS, 10% AH and 10% Leymus chinense hay (LC); ii) 20% corn silage, 20% alfalfa hay and 10% LC; iii) 10% CS, 30% AH and 10% LC. Cows were allowed to consume a total mixed ration ad libitum. There was no change of dry matter intake when cows were fed the experimental diets. As more AH was added to the diets, milk yield, milk protein content and yield, and trans9, cis11-conjugated linoleic acids (CLA) concentrations in milk fat and plasma increased. When ESB were supplemented to the diets, milk yield, and trans9, cis11-CLA concentration in milk fat and plasma increased. When 10% ESB was added to the diet containing 30% AH the trans9, cis11-CLA content (1.46 g/100 g of total fatty acids) in milk was the highest among all treatments. These results suggests that AH could replace part of a CS diet and be a good forage source of diet for dairy cows to improve milk yield and milk composition. Meanwhile, ESB could be included in the diet with high AH to improve

The effect of dietary ratios of corn silage and alfalfa hay on carbohydrate digestion and retention time of feed particles in the gastrointestinal tract of steers

Four Holstein steers fitted with duodenal cannula were used in a 4 x 4 Latin square design to investigate the effect of the combination of corn silage (CS) and alfalfa hay (AH) in different ratios on the ruminal and intestinal digestion of carbohydrates and feed particle passage rate. Steers were fed mixed diets containing both CS and AH in ratios of 80:20, 60:40, 40:60 and 20:80 on a dry matter basis at 95% of ad libitum feed intake. The increase of AH proportion in diets increased dry matter intake and ruminal digestion of dry matter, non-fiber carbohydrate, neutral and acid detergent fiber linearly. Ruminal digestibility of neutral detergent fiber showed a quadratic response, and total digestibility increased linearly with increasing AH proportion. Digestibility of acid detergent fiber in the rumen was not affected by the dietary treatments, but the total tract digestibility increased as the AH proportion increased. Mean retention time of feed particles in total compartment increased when the AH proportion increased from 20% to 60%, but decreased with further increase of the AH proportion. These results indicate that moderate combinations of CS and AH have an associative effect on ruminal fiber digestion, modifying particle movement in the rumen.

Effect of Varying Dietary Ratios of Alfalfa Silage to Corn Silage on Production and Nitrogen Utilization in Lactating Dairy Cows

Twenty-eight (8 ruminally cannulated) lactating, multiparous Holstein cows were blocked by DIM and randomly assigned to 7 replicated 4×4 Latin squares (28-d periods) to investigate the effects of different dietary ratios of alfalfa silage (AS) to corn silage (CS) on production, N utilization, apparent digestibility, and ruminal metabolism. The 4 diets contained (dry matter basis): A) 51% AS, 43% rolled high-moisture shelled corn (HMSC), and 3% solvent soybean meal (SSBM); B) 37% AS, 13% CS, 39% HMSC, and 7% SSBM; C) 24% AS, 27% CS, 35% HMSC, and 12% SSBM; and D) 10% AS, 40% CS, 31% HMSC, and 16% SSBM. Dietary crude protein contents were 17.2, 16.9, 16.6, and 16.2% for diets A, B, C, and D. All 4 diets were high in energy, averaging 49% nonfiber carbohydrates and 24% neutral detergent fiber. Intake of dry matter, yield of milk, 3.5% fat-corrected milk and fat, milk fat content, and apparent digestibility of neutral detergent fiber and acid detergent fiber all decreased linearly when CS replaced AS. Effects on fiber digestion and milk fat may have been due to increasing fluctuation in ruminal pH and time the pH remained <6.0 when CS replaced AS. Milk protein content increased linearly with increasing CS, but there were no differences in protein yield. There were linear increases in apparent N efficiency and decreases in N excreted in urine and feces when CS replaced AS. Production was depressed on the diet highest in CS. Quadratic analysis indicated that milk and protein yields were maximal at dietary AS:CS ratios of, respectively, 37:13 and 31:19. No diet minimized N excretion without negatively affecting production. Diet C, with an AS:CS ratio of 24:27, was the best compromise between improved N efficiency and sustained production. Because CS is complementary with AS, it is recommended that CS be fed in AS-based diets to maintain milk yield while improving N utilization.

Digesta Passage Measured by Markers in Dairy Cows Fed Two Ratios of Corn Silage:Grain with 0 or 1.2% Sodium Bicarbonate

Four multiparous Holstein cows in midlactation fitted with rumen cannulae were in a 4×4 Latin square experiment to examine effects of two ratios of corn silage:grain (50:50 or 75:25) and sodium bicarbonate (0 or 1.2% of ration dry matter) on rate of passage of digesta. Marker techniques and mathematical equations were compared. Markers for liquid phase were polyethylene glycol and cobaltethylendiaminetetraacetic acid and for particulate phase were lanthanum, samarium, cerium, and chromium-mordanted fiber. A single compartment model was used to measure rate of passage of liquid from concentration of the two markers in ruminal fluid samples. Two two-compartment mathematical models were used to calculate rates of passage of liquid, grain, and fiber from fecal marker concentration. Ruminal liquid volume, rate of flow, and fractional rate of passage were not affected by sodium bicarbonate but increased with greater silage feeding. Ruminal grain and fiber passage were increased when more corn silage was fed. Effects of sodium bicarbonate on ruminal grain and fiber passage were variable, although fiber passage tended to be slowed. Overall, liquid passage exceeded grain passage, which exceeded fiber passage from the rumen. In the total tract, retention time of liquid, grain, and fiber was less when diets contained 75% corn silage. The effect of sodium bicarbonate on retention time of liquid, grain, and fiber in the total tract was variable. Markers and mathematical calculations caused differences in estimates of rate of passage and interpretation of results.

Effects of 1.2% Sodium Bicarbonate with Two Ratios of Corn Silage:Grain on Milk Production, Rumen Fermentation, and Nutrient Digestion by Lactating Dairy Cows

Four multiparous Holstein cows in mid lactation fitted with rumen cannulae were in a 4 × 4 Latin square experiment to study the effects of sodium bicarbonate and ratio of corn silage:grain on milk production and composition, feed intake, rumen fermentation, and nutrient utilization. Cows were fed diets of 50:50 or 75: 25 corn silage:grain with 0 or 1.2% sodium bicarbonate. Experimental periods were 21 days with 15 days for adaptation to diet and 6 days for data collection.Milk fat percent and 4% fat-corrected milk production (kg/day) were higher for cows fed diets containing 1.2% sodium bicarbonate (3.69 and 23.1 versus 3.03 and 19.3). Sodium bicarbonate and ratio of corn silage:grain had no effect on dry matter intake. Rumen pH was higher 1 and 3h postfeeding with added sodium bicarbonate (5.64 versus 5.83). Sodium bicarbonate increased total volatile fatty acids (91 versus 105 mm/liter), increased molar proportions of acetate, butyrate, and isovalerate, and decreased propionate and valerate. Dry matter, organic matter, and neutral-detergent fiber digestibilities were higher for cows fed diets composed of 50% grain compared with diets with 25% grain. Acid-detergent fiber digestibility was increased by sodium bicarbonate (47.7 versus 52.9%). Protein digestibility and nitrogen utilization were not affected by added sodium bicarbonate or the ratio of forage:grain. In summary, sodium bicarbonate added at 1.2% of the total dry matter to diets containing 50:50 and 75:25 corn silage:grain increased milk fat percent, fat-corrected milk production, rumen acetate:propionate, and utilization of acid detergent fiber.

Effect of feeding system on performance and carcass characteristics of yearling steers, steer calves and heifer calves.

Three types of cattle (Angus x Hereford yearling steers, Charolais x British breed steer calves and Hereford heifer calves) were evaluated for their response to different feeding systems utilizing high moisture corn, corn silage and soybean meal as major feed ingredients. Feeding ing systems for steers included: A = 85% concentrate; B = 40% concentrate; C = two phase, with switch from all corn silage to 85% concentrate in the middle of the feeding period; D = same as C except switch occurred late in the feeding period; E = all corn silage continuously. Heifer diets consisted of the following ratios of corn silage to concentrate: low energy = 89:11; medium energy = 67:33; and high energy = 100 fed at a moderate (10.9% for low energy and medium energy, and 11.7% for high energy) and high (13.8%) crude protein level. Treatments within each experiment were terminated at approximately the same final weight. Increasing percentage corn added to the total diet increased ADG in most comparisons. Adjusted to a constant carcass weight, increasing dietary energy increased fat thickness and reduced percentage retail product with no effect on quality grade in yearling steers and heifer calves. In Charolais cross-steer calves, increasing energy level increased quality grade with no effect on yield grade or percentage retail product. Energetic efficiency slightly favored system C in yearling steers while steer calves maximized efficiency on A. Hereford heifers were the most energetically efficient on medium energy diets.