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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Effects of Corn Silage Hybrids and Dietary Nonforage Fiber Sources on Productive Performance in Early Lactating Dairy Cows Fed High Forage Diets

Holt, Michael Shane 01 May 2010 (has links)
This experiment was conducted to determine the effects of corn silage hybrids and nonforage fiber sources (NFFS) in high forage diets formulated with high dietary proportion of alfalfa hay (AH) and corn silage (CS) on ruminal fermentation and productive performance by early lactating dairy cows. Eight multiparous Holstein cows (4 ruminally fistulated) averaging 36 ± 6.2 d in milk were used in a duplicated 4 × 4 Latin square design experiment with a 2 × 2 factorial arrangement of treatments. Cows were fed 1 of 4 dietary treatments during each of the four 21-d periods. Treatments were: 1) conventional corn silage (CCS)-based diet without NFFS, 2) CCS-based diet with NFFS, 3) brown midrib corn silage (BMRCS)-based diet without NFFS, and 4) BMRCS-based diet with NFFS. Diets were isonitrogenous and isocaloric. Sources of NFFS consisted of ground soyhulls and pelleted beet pulp to replace a portion of AH and CS in the diets. In vitro 30-h NDF degradability was greater for BRMCS than CCS (42.3 vs. 31.2%). Neither CS hybrids nor NFFS affected intake of DM and nutrients. Digestibility of N, NDF, and ADF tended to be greater for cows consuming CCS-based diets. Milk yield was not influenced by CS hybrids and NFFS. However, a tendency for an interaction between CS hybrids and NFFS occurred with increasing milk yield due to feeding NFFS with the BMRCS-based diets. Yields of milk fat and 3.5% FCM decreased when feeding the BMRCS-based diet, and there was a tendency for an interaction between CS hybrids and NFFS by further decreased milk fat concentration because of feeding NFFS with BMRCS-based diet. Although feed efficiency (milk/DM intake) was not affected by corn silage hybrids and NFFS, there was an interaction between CS hybrids and NFFS because feed efficiency increased when NFFS was fed only with BMRCS-based diet. Total VFA production and individual molar proportion were not affected by diets. Dietary treatments did not influence ruminal pH profiles except that duration (h/d) of pH < 5.8 decreased when NFFS was fed in CCS-based diet but not in a BMRCS-based diet, causing a tendency for an interaction between CS hybrids and NFFS. Overall measurements in our study reveal that high forage NDF concentration (20% DM on average) may eliminate potentially positive effects of BMRCS. In the high forage diets, NFFS exerted limited effects on productive performance when they replaced AH and CS. Although the high quality AH provided adequate NDF (38.3% DM) for optimal rumen fermentative function, the low NDF concentration of the AH and the overall forage particle size reduced physically effective fiber and milk fat concentration.
262

Silage Corn Hybrid Response to Row Width and Plant Density in the Intermountain West

Pieper, Mark A. 01 August 2018 (has links)
Corn (Zea mays L.) hectarage has increased rapidly in Utah and Idaho in recent years due to expansion of the dairy industry, but little is known about corn production practices that optimize yield and quality of silage corn in semi-arid irrigated cropping systems. The objective of this study was to determine the dry matter yield and quality effects of corn hybrids grown in different plant densities and row widths in the Intermountain West. Field experiments were conducted under irrigation in 2015 and 2016 at locations near North Logan, Utah and Jerome, Idaho. The experimental design was a randomized complete block in a split-split plot arrangement with four replications. The whole plot treatment was hybrid (DKC 49-29, DKC 56-54, and DKC 61-88), the sub-plot treatment was row width (76 and 51-cm), and the sub-sub plot treatment was plant density (61,776 to 123,552 plants ha-1 at intervals of 12,355 plants ha-1). The 51-cm row width resulted in forage dry matter yield increases of 4-7% over corn in 76-cm rows. Hybrids differed in response to row width, with no difference detected for the 99-RM hybrid but a significant yield increase for the 106- and 111-RM hybrids by planting in narrow rows. Yield increased quadratically as plant population increased from 61,776 to 123,552 plants ha-1 for all hybrids. The only forage nutritive value that was influenced by row spacing was crude protein (CP), where the 76-cm row spacing showed a 4.5% advantage over the 51-cm row width. Starch increased approximately 3% from the lowest to highest plant densities tested. Net returns showed possible positive increases when comparing row width adjustments. Silage corn yield and quality in the Intermountain West appears to be optimized in 51-cm rows at a plant population between 86,487 and 98,842 plants ha-1.
263

Studies on Utilization of Food and Agricultural By-products as Total Mixed Ration Silage for Dairy Cows / 食品製造副産物および農業副産物を利用した乳牛用混合飼料サイレージの利用に関する研究

Srita Yani 25 November 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第18659号 / 農博第2088号 / 新制||農||1027(附属図書館) / 学位論文||H26||N4882(農学部図書室) / 31573 / 京都大学大学院農学研究科応用生物科学専攻 / (主査)教授 廣岡 博之, 教授 松井 徹, 教授 久米 新一 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM
264

Effects of inoculation on alfalfa silage quality and its feeding on the performance of dairy cattle

Rizk, Charbel January 2004 (has links)
No description available.
265

Barley silage harvested at boot and soft dough stages for lactating cows

Acosta, Yamandu Martin 01 August 2012 (has links)
Barley (Hordeum vulgare, L.) harvested at boot (5/7/88) and soft dough (6/6/88) stages of maturity was ensiled for nutritive comparisons. Boot stage was wilted and soft dough was direct cut at 15 (SD-Lo) and 25 cm (SD-Hi) above ground. Yields (kg DM/ha) were 3690, 8750 and 6287 for boot, SD-Lo and SD-Hi respectively. Digestibilities (%) of DM, CP and ADF were 74.7, 74.5 and 70.8 for boot; 61.9, 50.4 and 44.7 for SD-Lo; and 62.3, 47.2 and 49.7 for SD-Hi, respectively. Calculated TDN was 71.2, 62.0 and 62.8 for boot, SD-Lo and SD-Hi, respectively. Thirty-six lactating Holstein cows were fed boot silage at 75 and 60% of diet DM, SD-Lo fed at 75 and 60 and SD-Hi fed at 75 and 60, respectively. Milk yields (kg/d) were greatest for high concentrate diets and averaged 25.7, 28.3, 24.8, 26.3, 25.7 and 26.9, respectively. There were no differences among diets for DM intake or 4% FCM. Boot silage had a greater In Situ rumen degradability of DM, CP, ADF and NDF (68.6, 89.3, 44.2 and 45.1% respectively) than SD-Lo (57.8, 76.9, 20.9 and 24.2%) and SD-Hi (62.5, 80.0, 22.8 and 26.4%). Predictability of ruminal degradability of complete diets from weighted averages of single ingredients determined separately was low. In Situ incubation of single ingredients resulted in underestimation of DM and overestimation of CP degradability compared with complete diet incubation. / Master of Science
266

Effects of potassium, magnesium, and sulfur fertilization on corn grain and silage yields in a high nutrient soil

Badra, Abdo January 1990 (has links)
No description available.
267

Community Decision Making Aids for Improved Pasture Resources in the Madiama Commune of Mali

El Hadj, Meriem 08 December 2004 (has links)
The lack of forage resources in the Sahelian region of Mali is a major constraint to food production and food sufficiency. Madiama commune is located in northern Mali, in the Niger Delta region. Three separate experiments were conducted to investigate ways to improve pasture resources and productivity. The first experiment (2003) was designed to investigate the influence of sheep grazing tethered at two different residual heights on botanical composition, forage biomass and animal performance. Young sheep weighing approximately 18-24 kg were tethered for a certain period of time depending on residual canopy height. Two treatments 3 or 6 cm residual height were each replicated 4 times. Animals were rotated based on canopy height and each tethered animal followed an 8 paddock rotation. Measurements included forage biomass, plant diversity, animal performance, and botanical composition. The forage species found on these pastures were primarily Schoenfeldia gracilis, Panicum laetum, Setaria palludefusca, Eragrostis turgida, Eragrostis tremula, Zornia glauchidiata, Tephrosia pedicellata, and Cynodon spp. Accumulated seasonal forage biomass increased while forage quality declined as the growing season progressed. Treatment had only a slight effect on animal weight gains (1 to 3kg season-1). These results suggest that residual height may not affect livestock gain. The second experiment was designed to investigate the potential of Cassia tora (C. tora) which is an invasive weed in the region as a supplemental feed for livestock. Cassia tora was harvested within the Madiama commune and ensiled with or without additives (water and or honey/sugar) for 60 or 90 days. Harvest occurred at the vegetative stage in year 1 and mature growth stage in year 2. Prior to placing the chopped material in the bags for ensiling, sub-samples of fresh C. tora were obtained for dry matter (DM) and chemical analysis (NDF, ADF, CP, IVDMD and TDN). In year 1, the ensiled material/fresh material across treatments and locations had NDF varying from 48 to 56 %/ 56 to 57%, ADF from 34 to 41 %/40 to 42%, CP from 9 to 10 %/9 to 23%, and IVDMD from 53 to 64 %/52 to 54%. In year 2, CP averaged twice as much as year 1 with significantly less fiber probably due to the fact that harvest occurred at the vegetative stage. Addition of water or sugar/honey improved the nutritive values of the ensiled material. These results suggest that C. tora can be a reliable feed source during the dry season. A greenhouse experiment was conducted using various P sources (Tilemsi phosphate rock (TPR), North Carolina phosphate rock (NCPR), Aluminum phosphate (AlP), Iron phosphate (FeP), and Triple superphosphate (TSP) and rates (0, 20, 40, 60, and 80 mg P kg-1 soil). Plants were grown for 10 wks, harvested and separated into above and below ground plant parts. The root and plant material were dried, ground and analyzed for elemental P. The result showed variable P solubility and uptake by the plant. Overall, addition of P resulted in an increase in above ground biomass as well as root mass compared with the untreated control. Field and greenhouse experiments showed that in the Sahel region of Africa where feed resources are scarce 8 out of 12 months a year, anything we can do to increase pasture resources and animal productivity while maintaining a healthy ecosystem, could improve the quality of life in the community. / Ph. D.
268

The Effects of European corn borer on whole-plant yieldand root knot nematode fitness in corn

Tiwari, Siddharth 07 May 2007 (has links)
Field studies were conducted over two growing seasons to evaluate the effect of different levels of third instar European corn borer, Ostrinia nubilalis Hübner (Lepidoptera: Crambidae), on whole-plant dry matter in corn grown for silage. Mean (± SEM) whole-plant dry matter was significantly greater by 18.8% in uninfested control plants than in plants with an infestation level of 6 larvae/plant in 2004. Whole-plant dry matter in 2005 was significantly greater by 10.5% in control plants than in plants with an infestation level of 5 larvae/plant. Economic injury levels were calculated for each year using regression equations between whole-plant dry matter and European corn borer infestation level. Plant growth stage and infestation level had no effect on percent acid detergent fiber, neutral detergent fiber, and crude protein values for either year. Greenhouse studies were conducted to examine the relationship between aboveground herbivory by European corn borer and belowground herbivory by root knot nematode, Meloidogyne incognita Chitwood (Tylenchida: Heteroderidae), in corn. Two experiments were conducted to measure belowground herbivory by M. incognita in juvenile penetrations and eggs/root system. In the first experiment, the main effects interaction was not significant for either M. incognita juvenile penetrations or eggs/root system. Overall mean juvenile penetrations/root system across all three growth stages, at infestation levels of 1 and 3 larvae/plant were significantly less than in the non-infested control. In addition, overall mean eggs/root system at an infestation level of 3 larvae/plant were significantly less than in the control. In the second experiment, the main effects interaction was significant for both juvenile penetrations and eggs/root system. At the 8 and 10 leaf growth stages, juvenile penetrations/root system at infestation levels of 1 and 3 larvae/plant were significantly less than in the control. In addition, eggs/root system at an infestation level of 3 larvae/plant were significantly less than in the control, at all growth stages. In the reciprocal study, which examined the effect of different M. incognita inoculation levels on European corn borer stalk tunneling, no significant effect of inoculation level on European corn borer stalk tunneling was found. / Ph. D.
269

Fermentation characteristics and nutritional value of stored and fresh dairy cattle waste ensiled with crop residues

Abazinge, Michael D. A. January 1983 (has links)
A small silo study was conducted to determine the optimum combination of slurry and fresh dairy waste and crop residues to achieve good ensiling. Slurry waste that had been accumulated in slurry storage tanks and dairy waste scraped from the barn were ensiled with ground corn stover, with and without the addition of 5% molasses, to achieve two dry matter levels of 30 and 35%. Fermentation, as measured by pH, lactic acid and disappearance of soluble carbohydrates, occurred in all silage mixtures. Lactic acid levels indicated that a more desirable fermentation had occurred in the waste silages containing molasses. Total and fecal coliforms and salmonella, shigella and proteus organisms were either destroyed or essentially eliminated following ensiling. A large silo study was conducted with the mixtures containing molasses. The fresh waste was diluted with water to achieve the same dry matter levels as the slurry waste. The mixtures for the 30 and 40% dry matter levels were 71:39 and 64:36 cattle waste to wheat straw, wet basis. Active fermentation occurred in all silages and pH was lower and lactic acid levels were much higher than they were in the small silo. In a metabolism trial conducted with lambs, the following diets were fed: 1) 50% orchardgrass hay, 38.3% ground corn, 11.4% soybean meal and .3% limestone (basal diet); 2) 50% basal and 50% ground wheat straw ensiled at 50% dry matter (negative control); 3) 50% basal and 50% 71:29 slurry-wheat straw silage; 4) 50% basal and 50% 64:36 slurry-wheat straw silage; 5) 50% basal and 50% 71:29 fresh waste-wheat straw silage and 50% basal and 50% 64:36 fresh waste-wheat straw silage (proportions of basal and silages were on a dry basis). Apparent dry matter digestibility was higher (P < .01) for the basal diet than for the silage diets and was higher for the waste containing silages (P < .05) than for the wheat straw silage diet. Dry matter digestibility of the waste-containing silages, calculated by difference, was not different, but was higher (P < .01) than for the ensiled wheat straw alone. Nitrogen digestibility was higher (P < .05) for the waste containing silages, compared to the wheat straw silage but lower (P < .05) than the basal ration. All lambs were in positive nitrogen balance, with the lambs fed the 71:39 slurry waste silage slightly higher than for those fed the other diets. The lambs fed the basal and wheat straw silages had similar nitrogen retention. Ruminal ammonia levels were highest (P < .05) for the lambs fed the basal and lowest for those fed the wheat straw silage diet. There were no significant differences (P < .05) among the waste-containing silages. The palatability trial with lambs was conducted using 50% basal and 50% of the silages, dry basis. Dry matter intake was highest (P < .05) for the basal diet. Dry matter intake among the silage diets was lowest (P < .05) for the slurry waste silage diets. Among the waste-containing silage diets, dry matter intake tended to be higher for the fresh waste silages, compared to the slurry waste silages of similar dry matter. / M.S.
270

Methods of preserving and enhancing fermentation and nutritional value of caged layer waste-wheat straw silages fed to sheep

Ayangbile, Gbemiga A. January 1986 (has links)
Three experiments were conducted with fresh caged layer waste collected within 24 h after excretion. The waste was stored uncovered for 42 d in polyethylene lined 210 liter metal drums. In the first experiment, waste was treated with no additive, 1 and 1.5% formaldehyde, 1.5 and 2% sodium metabisulfite and 1. 5 and 2% propionic/formic acid (1: 1, w/w). In the second experiment, the additives used were: none, 1% formaldehyde, 1.5% sodium metabisulfite, 1.5% propionic/formic (1: 1, w/w), 10% dry sugar cane molasses and 10% dry molasses plus 2% sodium chloride (salt). In this experiment, the wastes were ensiled with wheat straw (60:40, wet basis) in 4-liter cardboard containers double lined with polyethylene with the following additives: control, 10% dry molasses, silage inoculant or 10% dry molasses plus inoculant. In the third study, the preservatives were: untreated, 1% formaldehyde, 10% dry molasses or 10% dry molasses and 2% salt. After 42 d, treated wastes and straw (60:40) were ensiled with 10% dry molasses in 210 liter metal drums doubled lined with polyethylene. A metabolism trial was conducted with 30 crossbred wethers fed a basal diet alone or with silages containing the wastes which had been treated with the preservatives (1:1, dry basis). In all studies, putrefaction, maggot infestation and dark color were observed for untreated waste. The tops of the wastes treated with sodium metabisulfite and formaldehyde were covered with mold. Formaldehyde-treated waste maintained a stable pH, and water-soluble carbohydrate level. The higher level of propionic/formic acid was effective against visible deterioration. The pH of the silages containing molasses-treated waste was lower than for silages containing control or chemically-treated wastes. Adding molasses at ensiling reduced pH and increased lactic acid. Digestibilities of organic matter, crude protein and neutral detergent fiber were lower (P<.05) for the diet containing silage made from untreated waste, compared to diets containing silage made from treated waste. In all studies, putrefaction, maggot infestation and dark color were observed for untreated waste. The tops of the wastes treated with sodium metabisulfite and formaldehyde were covered with mold. Formaldehyde treated waste maintained a stable pH, and water-soluble carbohydrate level. The higher level of propionic/formic acid was effective against visible deterioration. The pH of the the silages containing molasses-treated waste was lower than for silages containing control or chemically-treated wastes. Adding molasses at ensiling reduced pH and increased lactic acid. Digestibilities of organic matter, crude protein and neutral detergent fiber were lower (P<.05) for the diet containing silage made from untreated waste, compared to diets containing silage made from treated waste. / Master of Science

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