No description available.

No description available.

No description available.

No description available.

A metabolism trial and a feedlot finishing trial were conducted with silage made from corn (Zea mays L.) forage grown by conventional and sustainable methods. For the metabolism trial, 24 wether lambs were allotted to four diets: 1) conventional corn silage supplemented with urea, 2) conventional corn silage supplemented with soybean meal (SBM), 3) sustainable corn silage supplemented with urea, and 4) sustainable corn silage supplemented with broiler litter. Apparent DM digestibilities were 65.9, 69.3, 63.8, 66.2%, for the respective diets. Apparent digestibilities of NDF, ADF, and cellulose were lower (P < .05) for the urea-supplemented diets than the SBM and broiler litter supplemented diets. Sheep fed sustainable silage supplemented with broiler litter had the highest (P < .05) fecal N excretion, due to at least partly to the highest (P < .05) N intake. Total N excretion was similar (P > .05) among sheep fed all diets. Sheep fed conventional and sustainable silages supplemented with urea were in negative N balance (-1.04, and -.38, respectively). Sheep fed the conventional silage supplemented with SBM and sustainable silage supplemented with broiler litter had similar (P > .05) positive N retention. Conventional and sustainable silages were fed to feedlot steers and supplemented with either SBM or broiler litter. Conventional steers had a higher (P < .05) live weight (421 kg) upon entering the feedlot than the steers fed the sustainable diet (390 kg). Difference in ADG did not become apparent until the second-to-last 28-d period, at which time the conventional steers had a higher (P < .05) ADG than the steers fed the sustainable diet. Cattle fed the sustainable diet tended to consume more feed (P > .05) and had lower gain/feed (P < .05) than those fed the conventional diet. At slaughter, cattle fed the conventional diet were heavier (P < .05), (596 vs 541kg). Carcass maturity, marbling, backfat, percent kidney, pelvic and heart (KPH) fat, and quality grade were similar (P > .05) for the cattle fed the two diets. Carcass weight, ribeye muscle area, yield grade and dressing percentage were higher for the cattle fed the conventional diet, reflecting higher liveweight than cattle fed the sustainable diet. / Master of Science

The extraction of fifteen (15) polymer additives with supercritical carbon dioxide which are used as antioxidants, uv stabilizers, process lubes, flame retardants and antistats from eight formulations of polystyrene is demonstrated and compared to traditional dissolution/precipitation extractions. The purpose of the study was twofold: 1) the development of a high performance liquid chromatography (HPLC) method(s) for the additives and 2) the determination of the viability of supercritical fluid extraction (SFE) for the additives from polystyrene. Separation of some of the additives was achieved using reversed phase liquid chromatography. Nine of the additives were assayed in this manner while, the remaining six additives could not be assayed using reversed phase liquid chromatography. In order to develop an extraction method for the additives, the effects of static extraction time, CO2 density, and temperature were first investigated. These preliminary extractions revealed that a static extraction period which afforded an opportunity for the polymer to swell combined with a high CO2 density and extraction temperature above the glass transition (Tg) yielded quantitative recoveries of the additives. Triplicate extractions of the various polystyrene formulations matched additive recoveries obtained by the traditional dissolution/precipitation method. / Master of Science

The following study was conducted to investigate the antibacterial and feed additive potential of medicinal plants. Ethanol extracts of different medicinal plants including Curcuma longa (Turmeric), Zingiber officinale (Ginger), Piper nigrum (Black Pepper), Cinnamomum cassia (Cinnamon), Thymus vulgaris (Thyme), Laurus nobilis (Bay leaf), and Syzgium aromaticum (Clove) were tested using the disc diffusion method for their antimicrobial activity against the common poultry pathogens E. coli, S. typhimurium, E. faecium, and E. faecalis. Cinnamon extract (CE), at 130 mg/disk, exhibited antibacterial activity against E. coli, S. typhimurium, and E. faecalis. Thyme extract (TE), at 30 mg/disk, exhibited antibacterial activity against E. coli, E. faecium, and E. faecalis while the remaining medicinal plants extracts showed no activity. The minimum inhibitory concentration (MIC) of the cinnamon and thyme ranged from 31.25 to 250 mg/ml by the dilution method. From this in vitro antibacterial study, cinnamon and thyme were selected for a 21-d feeding trial in broilers to study their influence on feed consumption, body weight gain, and feed conversion. There were 6 dietary treatments groups: 1) negative control (NC) containing no plant extracts or antibiotic, 2) positive control (PC) containing BMD (bacitracin) at 50g/ton of feed, 3) Diet 1 plus low level of cinnamon extract (LCE) at 290 gm/100 kg of feed, 4) Diet 1 plus high level of cinnamon extract (HCE) at 580 gm/ 100 kg of feed, 5) Diet 1 plus low level of thyme extract (LTE) at 290 gm/100kg of feed, and 6) Diet 6 plus high level of thyme extract (HTE) at 580 gm/100 kg of feed. No significant changes in body weight gain were observed with the cinnamon extracts compared to the NC or PC at 7, 14, or 21 d. The HTE reduced body weight gain compare to the NC and PC at 7, 14, and 21 d (P < 0.02). No difference in feed efficiency was observed with any of the treatments except LCE which reduced feed efficiency compared to other treatments. No difference in feed consumption was found among any of the treatments. These results suggest that cinnamon and thyme have antibacterial activity in vitro, and thyme has an activity that reduces body weight. Since cinnamon caused no significant change in body weight gain compared to positive or negative controls, it warrants further study as a substitute for antibiotics in the diet. / Master of Science

Specimens from 27 batches of concrete with water to cementitious (cement plus silica fume) ratio of 0.25 to 0.32, with and without entrained air, were tested for freeze-thaw durability in accordance with ASTM C666, procedure A (freezing and thawing in water). In addition, another set of similar specimens were moist cured for 28 days instead of 14 days and tested in accordance with ASTM C666 , Procedure A to determine the effect of curing time on the freeze-thaw durability of high strength concrete. Results show that non air-entrained high strength concrete with water cementitious ratio of less than 0.30, regardless of the length of curing time, is frost resistant. Non-air-entrained concrete with water-cement ratio of 0.32 is also durable if silica fume is not used. / Ph. D.

Pour une fonction additive f et une fonction multiplicative g , soit E ( f, g ; x ) := # { n ≤ x : f ( n ) = g ( n ) } . Dans cette thèse, nous améliorons le résultat de De Koninck, Doyon et Letendre relatif à l’ordre de grandeur de E ( ω, g ; x ) et E (Ω , g ; x ) . Nous obtenons aussi des résultats généralisant l’inégalité d’Hardy-Ramanujan et le théorème de Landau. De plus, nous appliquons la méthode de Selberg-Delange de façon à obtenir une formule relative à la fréquence des fonctions ω ( n ) et Ω( n ) en progression arithmétique. Finalement, nous trouvons une condition suffisante pour qu’une fonction arithmétique quel- conque possède une fonction de répartition et obtenons une version quantitative du théorème d’Erdős-Wintner. / For an additive function f and a multiplicative function g , let E ( f, g ; x ) := # { n ≤ x : f ( n ) = g ( n ) } . In this thesis, we improve the result of De Koninck, Doyon and Letendre regarding the order of magnitude of E ( ω, g ; x ) and E (Ω , g ; x ) . We also obtain results which generalise the Hardy-Ramanujan inequalities and the Landau theorem. Moreover, we use the Selberg-Delange method in order to obtain a formula on the frequency of the fonctions ω ( n ) and Ω( n ) in arithmetic progression. Finaly, we find a sufficient condition for an arithmetical function to possess a distribution function and obtain a quantitative version of the Erdős-Wintner theorem.

O objetivo desse trabalho foi descobrir melhores estratégias de controle de perdas em silagens de cana-de-açúcar, utilizando combinações de aditivos químicos e microbianos ou estratégias de vedações. No primeiro experimento o intuito foi estudar estratégias de controle de clostrídios em silagens de cana-de-açúcar aditivadas com cal virgem. Os tratamentos foram: 1) controle; 2) 1,5% cal virgem (Cal); 3) 1,5% cal virgem + 5×105 ufc/g Lactobacillus plantarum Ma 18/5U (Cal+LP); 4) 1.5% cal virgem + 5×105 ufc/g Lactobacillus buchneri 40788 (Cal+LB); 5) 1,5% cal virgem + 0,07% nitrito de sódio (Cal+Nitrito); 6) 1,5% cal virgem + 0,15% benzoato de sódio (Cal+Benzoato). Como silos experimentais foram utilizados baldes plásticos com capacidade de 20 L. A cal não foi eficiente em diminuir perdas em relação ao controle (20,6% e 19,1%, respectivamente) já as combinações cal+Benzoato, cal+Nitrito, cal+LB e cal+LP, diminuíram perdas, apresentando os valores de 11,2%, 14,1%, 14,1% e 13,9%, respectivamente. A estabilidade aeróbia das silagens tratadas com cal (172 h), cal+Benzoato (155 h) e cal+Nitrito (223 h), foram maiores em comparação às tratadas com cal+LB (49 h), cal+LP (48,4 h) e controle (51,9 h). A silagem controle apresentou menores contagens de clostrídios (3,26 log ufc/g) e os tratamentos Cal e Cal+LB apresentaram as contagens mais altas (6,74 log ufc/g e 5,96 log ufc/g, respectivamente), enquanto Cal+nitrito (5,24 log ufc/g), Cal+LP (4,63 log ufc/g) e Cal+benzoato (4,41 log ufc/g) apresentaram contagens intermediárias. Nenhum tratamento imposto foi capaz de controlar o crescimento de clostrídios estimulado pela cal virgem. No segundo ensaio o objetivo foi comparar filmes plásticos na vedação de silagens de cana-de-açúcar. Os tratamentos impostos foram: 1) filme de poliamida 45?m, recoberta com manta de polietileno para proteção contra raios ultravioleta e danos físicos (PA45+M); 2) filme de polietileno coextrusado com poliamida, dupla face, 125?m (PA125); 3) filme de polietileno, dupla face, 200?m (DF). Três silos tipo trincheira foram preenchidos simultaneamente e durante o abastecimento a cana-de-açúcar picada foi tratada com benzoato de sódio na dose 0,15% da matéria natural. Decorridos 90 dias de armazenamento, os silos foram abertos e as silagens utilizadas como ingredientes para alimentação de vacas em lactação. Quinze vacas Holandesas (615 kg PV) foram alocadas aleatoriamente em três Quadrados Latinos 3x3, com períodos de 18 dias. O consumo de matéria seca (CMS). Amostras de leite foram coletadas para análises de proteína, gordura, lactose, caseína, ácidos graxos livres, sólidos totais, Nuréico e contagem de células somáticas. O óxido de cromo foi utilizado como marcador externo para estimar a produção fecal. As diferentes estratégias de vedação não influenciaram a qualidade das silagens e, consequentemente, não afetaram o CMS 19,9 kg/dia, a produção 25,1 kg/dia e a composição do leite (gordura 3,5%, proteína 3,3%, lactose 4,4%), das vacas. As diferentes estratégias de vedação utilizadas não influenciam a qualidade das silagens de cana-de-açúcar e o desempenho de vacas leiteiras e se mostraram efetivas para vedação de silos horizontais. No presente estudo, tanto a utilização de aditivos como a adoção de estratégias de vedação não foram efetivas em controlar perdas em silagens de cana-de-açúcar. / The aim of this study was to discover the best strategies to control losses in sugarcane silages, using combinations of chemical and microbial additives or covering strategies. In the first trial the aim was to compare strategies to prevent clostridium grow in sugarcane silages added with lime. Treatments were Control: no additives; L: 1.5% lime; L + LP: 1.5% lime + Lactobacillus plantarum Ma 18/5U (5×105 cfu/g fresh forage); L + LB: 1.5% lime + Lactobacillus buchneri 40788 (5×105 cfu/g fresh forage); L + N: 1.5% lime + 0.07% sodium nitrite; L + B: 1.5% lime + 0.15% sodium benzoate. As experimental silos were used plastic buckets with a capacity of 20 L. Mini bags were prepared with the following treatments 1) control, 2) 1.5 % of lime and 3) 1.5 % of lime + 5 × 105 cfu/g of L. plantarum, in order to analyze the pH drop at the onset of fermentation. The lime was not effective in decreasing losses compared to control silages (20.6% and 19.1%, respectively) however the treatments lime+Benzoate, lime+nitrite, lime+LP and lime+LB, decreased losses, showing lower values: 11.2%, 14.1%, 14.1% and 13.9%, respectively. The aerobic stability of silages treated with lime (172 h), lime+Benzoate (155 h) and lime+Nitrite (223 h) were higher compared to those treated with lime+LB (49 h), lime+LP (48.4 h) and control (51.9 h). The control treatment showed the lowest counts of clostridia (3.26 log cfu/g) and treatment with lime and lime+LB had the highest counts (6.74 log cfu/g and 5.96 log cfu/g, respectively), while lime+nitrite (5.24 log cfu/g), lime+LP (4.63 log cfu/g) and lime+benzoate (4.41 log cfu/g) showed intermediate counts of clostridia. None of additives combined with lime were able to provide butyric acid free silages. In the second trial the aim was to compare plastic films for sealing sugarcane silages. Treatments were: 1) polyamide film 45?m plus a protection against physical damage and ultraviolet light (PA45 + P), 2) polyethylene film coextruded with polyamide, black-on--white, 125?m (PA125), 3) polyethylene film, blackon- white 200?m (BW). Three trench silos were filled out simultaneously with chopped sugarcane treated with 0.15% of sodium benzoate (as fed basis). After 90 days of storage, the silos were opened and silages fed to lactating cows as total mixed rations. . Fifteen Holstein cows (615 kg BW) were randomly allocated into 3x3 Latin square with periods of 18 days. Dry matter intake, diet apparent digestibility, milk yield and milk composition were evaluated on days 14 to 18 in each period. Chromium oxide was used as external marker to estimate fecal excretion. Sealing strategies had no influence on silage quality and cows performance. Dry matter intake (19.9 kg /day), milk yield (25.1 kg/day), and milk composition (fat 3.5%, 3.3% protein, and 4.4% lactose) were quite similar across treatments. The different sealing strategies do not affect sugarcane silage quality and dairy cows performance and proven effective for sealing horizontal silos. In the present study, neither additives nor covering strategies were effective in reducing losses in sugarcane silages.