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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.
11

Yield responses, mineral levels of forages and soil in old arable land planted to four legume pasture species in Lushington communal area, South Africa

Gulwa, Unathi January 2017 (has links)
This study was conducted in the old arable land located in Lushington communal area in the Eastern Cape province of South Africa. The objectives of the study were to assess the effect of legume introduction on biomass yield, forage and soil mineral levels of the arable lands planted to four leguminous pastures in four seasons. Planting was done in March and October 2008 in Lushington. All legumes were subjected to grow under rain fed conditions. Trifolium vesiculosum (arrowleaf clover), Lespedeza cuneata (sericea lespedeza), Trifolium repens (white clover) and Lotus corniculatus (birdsfoot trefoil) are the four forage legume species that were sampled for the purposes of this study. The four legume species persisted out of the fourteen species that were initially tested for adaptability and persistence in the environmental conditions of Lushington communal area. The legumes, grasses and soils from these legume plots were sampled to determine the effect of legume introduction on the forage yield, mineral contents of the companion grasses and soils over four seasons. Plant and soil samples were collected once in spring (November) 2013, summer (February), autumn (March) and winter (May) 2014 for biomass production, macro and micronutrients determination. Results indicated that legume inclusion and season affected (P < 0.05) the total dry matter (TDM) yield production. Plots with Lespedeza cuneata had the highest TDM (1843 kg/ha) and control plots had the least dry matter production (1091 kg/ha). Summer season provided the highest (P < 0.05) TDM compared to the other seasons. Both legume and grass quality was also affected (P < 0.05) by legume inclusion in different seasons. Accordingly, grasses harvested from Trifolium repens plot showed higher CP level (10.90 percent) than those harvested from other plots whereas the lowest grass CP content (6.90 percent) was measured in the control treatment. L. cuneate had the highest (P < 0.05) CP level (11.00 percent) and T. repens had the least CP (6.63 percent) level. Grasses harvested in autumn had the highest (P < 0.05) CP level (12.50 percent) and those harvested in winter had the least CP level (4.60 percent). Similarly, all legume pastures harvested in spring had superior (P < 0.05) CP (10.80 percent) levels and those harvested in winter had the least CP (3.50 percent) level. Legume inclusion had an effect (P < 0.05) on both grass and legume macro nutrient contents. Trifolium repens plot had the highest grass K (1.07 percent), Ca (1.50 percent) and Mg (1.83 percent), whereas there were lower K (0.12 percent), Ca (1.25 percent) and Mg (1.08 percent) contents in grasses harvested from the control and T. vesiculosum plots, respectively. In legumes, macro nutrient concentrations: K (0.68 percent), Ca (1.75 percent) were superior in the T. vesiculosum plot in comparison to other plots. Season also affected (P < 0.05) both grass and legume macro nutrient content. There was higher K (0.90 percent), Ca (1.30 percent) and Mg (0.94 percent) content in grasses harvested in autumn whereas there were lower levels in winter harvests. In legumes, superior K (0.74 percent) and Mg (1.87 percent) content were attained during spring while the least were measured in winter (0.07 percent) and autumn (0.75 percent), respectively. Likewise, both legume inclusion and season had an significant effect (P < 0.05) on the forages micronutrient levels. During spring, there was superior soil P content (36.28 mg/kg) while during autumn; there was less P (22.58 mg/kg) content. The highest SOC level (1.49 percent) was measured in the T. repens plot whereas the lowest SOC (1.15 percent) was attained in the control plot. The results of this study showed that grass legume mixtures produced forages with high nutrient content and herbage yield. Legume planting in the old arable lands has a potential to improve soil quality parameters such as soil P and SOC content.
12

The Effects of Injectable Trace Mineral Supplements in Donor Cows at the Initiation of a Superovulation Protocol on Embryo Outcomes and Pregnancy Rates in Recipient Females

Silva, Felipe January 2018 (has links)
Concentrations of trace minerals within the body are known to impact reproductive processes. Thus, the current study analyzed the effects of using an injectable trace mineral supplement containing selenium, zinc, copper, and manganese during a superovulation protocol on embryo outcomes in donor beef cows and further effects on pregnancy rate in recipient females. We hypothesized that an injectable trace mineral (TM) supplement provided to cows fed to meet known nutrient requirements would increase TM status and influence superovulation, embryo characteristics, and enhance pregnancy rates. Our findings indicate that the injectable TM increased concentration of Se within the liver. However, superovulatory response, embryo production, quality grade, and developmental stage were not influenced by TM status. In addition, embryo treatment did not influence pregnancy rate, gestation length, or calf body weight.
13

Effect of restricted growth rate and elevated levels of minerals and vitamins on feet and leg characteristics, soundness scores and metacarpal and metatarsal characteristics of growing boars

Lepine, Allan J. January 1982 (has links)
The effects of dietary energy level (ad libitum vs 75% of ad libitum) and mineral-vitamin intake (100 vs 150% NRC recommendations) on foot and leg development, incidence and severity of foot lesions, soundness scores and metacarpal and metatarsal characteristics of growing boars was studied. Boars assigned to the dietary treatments at 5 wk of age were serially necropsied beginning at 120 d of age. Foot and leg characterization was carried out at four periods (35, 122, 209 and 290 d of age) and at necropsy. Bone samples were obtained at necropsy. Toe measurements increased over time with outside toes larger than inside toes. The hind outside toe was consistently larger than the other toes. Mineral-vitamin level had little effect on toe measurements, while ad libitum feeding produced larger feet and legs as compared with limit-fed boars at an equal age. Correction for body weight differences removed the energy level differences and often produced trends favoring the limit-fed boars. Dietary treatment had little effect on the incidence and severity of pad or horn lesions, however, restricting feed intake produced boars more structurally sound in appearance. Bone size increased with age, while bone ether extract decreased and bone ash content increased. As age increased, Ca content of bone ash increased, P level remained unchanged and Mg, Cu, Zn, Fe and Mn levels decreased. Metatarsals were longer and heavier than metacarpals. Percentage of bone ether extract increased with ad libitum feeding while the 150% mineral-vitamin level resulted in increased percentage bone ash. At an equal age, bone size and mechanical characteristics were greater for ad libitum-fed boars, however, weight-correction produced trends favoring limit-fed boars. Greater bone wall thickness and mechanical characteristics resulted from elevated dietary mineral and vitamin levels. Little consistent correlation was apparent between toe area or volume and the incidence of foot lesions or among the incidence of lesions at the various locations on the front or hind feet. / M.S.
14

Avaliação de produtos comerciais para mineralização de bovinos leiteiros e de corte no Brasil / Evaluation of commercial mineral supplements for dairy and beef cattle in Brazil

Diniz, Igor de Oliveira Barata 10 July 2014 (has links)
Made available in DSpace on 2015-03-26T13:55:24Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1753652 bytes, checksum: 23724be0973af46287264619b5b0e719 (MD5) Previous issue date: 2014-07-10 / This is a data survey from the main commercial mineral supplements for dairy and beef cattle currently available in the Brazilian market. 307 products have been listed, from eight of the leading companies operating in Brazil. The products have been listed in six categories: ready-to-use for beef cattle ; ready-to-use for dairy cattle ; units to produce beef cattle concentrate ; units to produce dairy cattle concentrate ; premix , which must be added to NaCl; and protein salts n order to evaluate their minerals, vitamins, ionophores, yeast, urea and crude protein composition, and compare the mineral levels with the Brazilian legislation (IN12, 2004). The ready to use products do not fulfill the legal specifications for phosphorus level in all products. The same happens in some "premix" products in 1:1 dilution with NaCl, when indicated for dairy cattle. This mineral level is 64.9 % higher in products to produce dairy cattle concentrate , when compared with the same kind of products for beef cattle. The P average for protein salts category is 28.5 g/kg and in order to meet the legal specifications, the ingestion must be considered. When it comes to micro minerals the premix category does not comply with the specifications in Cu , Mn , Zn and Se in 1:1 dilution for dairy cattle. The ready to use category meets all minerals specifications for dairy cattle but it does not for beef cattle, only part of the mineral range. Dairy cattle products to produce concentrate have higher viimicrominerals levels than those used for beef cattle, and the protein salts have lower levels compensated by higher ingestion. The legislation does not detail all animal categories. This fact is associated with some other factors as the large territory and massive herd make the Brazilian market gather around the conditions to group an extensive range of products. Therefore, the current legislation itself is not able to mold products for each mineral supplements situation that can occur in all Brazilian production systems. / Foi realizado um levantamento de dados dos principais suplementos minerais voltados para a bovinocultura leiteira e de corte disponíveis atualmente no mercado brasileiro. Foram listados 307 produtos, de oito das principais empresas desse segmento no Brasil. Os produtos foram elencados em seis categorias: produtos prontos para utilização para gado de corte ; produtos prontos para utilização em gado leiteiro ; núcleos para fabricação de concentrado para gado de corte , núcleos para fabricação de concentrados para gado leiteiro; premix ou produtos a serem misturados ao NaCl; e proteinados. Objetivou-se agrupar as composições de minerais, vitaminas, ionóforos, levedura, ureia e proteína bruta, bem como comparar os níveis minerais dos produtos com a legislação pertinente (IN 12, 2004). Os níveis de P não atendem às especificações da legislação em todos os produtos prontos para uso. Na categoria premix , a diluição em 1:1 com o NaCl não atende à totalidade dos produtos quando a indicação é para bovinos leiteiros. Para os núcleos de fabricação de concentrado, os níveis desse mineral são 64,9% mais altos nos produtos destinados à pecuária leiteira do que nos produtos para corte. Nos proteinados, a média do P ficou em 28,5 g/kg, e seu atendimento às especificações do MAPA depende do consumo. Os teores de microminerais na categoria premix não atendem às especificações para os microminerais Cu, Mn, Zn e Se em diluição de 1:1 para bovinos de leite. Nos produtos prontos para uso em bovinos leiteiros, os níveis mínimos de micros atendem às vespecificações do MAPA; já nos produtos para bovinos de corte, esses níveis não são atendidos em todos os micros. Os núcleos para rações também possuem médias mais altas nos produtos para leite, em comparação aos de corte, e os proteinados possuem médias baixas fato compensado por maiores consumos. Observou-se que a legislação não discorre detalhadamente sobre todas as categorias de animais e que outros fatores, como grande extensão territorial e rebanho massivo, criaram situações para que o mercado brasileiro reunisse uma gama muito extensa de produtos. Assim, a legislação atual, por si só, não é capaz de moldar os produtos destinados à mineralização bovina para atender a todas as situações que ocorrem nos diversos sistemas de produção brasileiros.
15

Exigências nutricionais, frequência de alimentação e níveis de cálcio e fósforo para bovinos Holandês x Zebu em confinamento / Nutritional requirements, feeding frequency and levels of calcium and phosphorus for Holstein x Zebu steers in confinement

Zanetti, Diego 22 July 2014 (has links)
Made available in DSpace on 2015-03-26T13:55:25Z (GMT). No. of bitstreams: 1 texto completo.pdf: 840074 bytes, checksum: f585a1e0847e000c0f9ccf71f306abb8 (MD5) Previous issue date: 2014-07-22 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / This work was developed in order to evaluate the feed intake, digestibility and performance of crossbred cattle fed in confinement at different frequencies with diets containing different levels of calcium and phosphorus; determine the nutritional requirements of energy, protein and macro minerals; and evaluate the effects on consumption estimates when reducing the number of samples of leftovers for laboratory analyses by grouping these samples in the total period of the confinement. For that were used 32 1&#8260;2 crossbred Gir x Holstein barrows, with mean 377.46 ± 49.4 kg of initial body weight. Initially, four animals were slaughtered and used as a reference to estimate the initial empty body weight (EBW) of the remaining animals in the experiment. 24 animals were used in a completely randomized factorial 2x3x2 design with two concentrate diet levels (30 and 60%), three frequency (full diet fed in the morning, at 8:00 am; roughage provided in its entirety in the morning and concentrate divided into twice, at 8:00 and at 16:00 hours; and feeding roughage and concentrate divided into two equal portions per day) and diets with or without inorganic sources of calcium and phosphorus. The four other animals were fed daily at maintenance level (1.1% body weight on dry matter). The roughage used was crushed sugar cane. At the end of 84 days all animals were slaughtered and samples from the carcasses and not carcass constituents were taken to determinate composition. Chapter 1: The dry matter (DM) and nutrients were not affected (P> 0.05) by feeding frequencies but were higher (P <0.05) for diets with 60% of concentrate. Supplementation with dicalcium phosphate affected only the consumption of phosphorus that was higher for supplemented diets. There was no effect of feeding frequency, supplementation with dicalcium phosphate or their interactions (P> 0.05) on the digestibility of diets constituents. Higher levels of concentrate provided higher average of daily gains and income from hot and cold carcass. In Chapter 2: The net (NEm) and metabolizable energy (MEm) requirements for maintenance were obtained by relating heat production (CP) and metabolizable energy intake (MEI) while the energy requirements for weight gain (NEg ) and net protein requirements for weight gain were obtained as a function of EBW and empty body weight gain (EBWG). The daily requirements of metabolizable and net energy for maintenance were 86.48 and 126.15 kcal / PCVZ 0.75 respectively. The requirements for net energy gain can be obtained by the equation: NEg = 0.0568 ± 0.0025 × × PCVZ0,75 GPCVZ1,095. The efficiency of use of metabolizable energy for maintenance and gain are 64 and 29.68%, respectively. The metabolizable protein requirement for maintenance is 4.14 g / BW 0.75. The net protein requirements for weight gain can be obtained through the equation PLg = 236.36 ± 30.06 × EBW - 19.84 ± 6.14 × ER. Third chapter: The relationship between the consumption of each mineral and it retention was expressed as a linear equation, and the intercept considered the requirement for maintenance of the mineral. Using the samples of the carcass and no carcass were determined the proportion of each mineral, determining the body content for each mineral expressed as a function of EBW. No variations in daily fecal and urinary excretions of phosphorus according to the supplementation with dicalcium phosphate were found. The absence of dicalcium phosphate supplementation in cattle diets in the finishing phase implies lower retention of calcium and phosphorus in the carcass. The absorption coefficients were 83.34, 77.21, 82.57, 40.27 and 92.25% for calcium, phosphorus, sodium, magnesium and potassium, respectively. The net daily maintenance requirements are 28.18, 10.31, 50.11, 25.86, and 91.67 mg / EBW for calcium, phosphorus, magnesium, sodium and potassium, respectively. Net requirements for calcium, phosphorus, magnesium, sodium and potassium for weight gain can be calculated respectively by the equations: Ca = × EBW (EBW-51.77 × 0.3023); P = EBWG × (30.87 × EBW-3459); EBW = mg × (0.865 × EBW-0.2133); In EBW = × (6.517 × EBW-0.3483); EBW = K × (4.06 × EBW-0.1875). It is concluded that the intake, digestibility of nutrients and performance were not affected by the feeding frequencies adopted or by the levels of calcium and phosphorus added, but were improved with increasing level of concentrate. About the sampling of leftovers, it is recommended to make a single composite sample for 84 days of confinement. The values and equations obtained for the requirements of crossbred Holstein × Zebu differs from that obtained by Br- Corte (2010), emphasizing that the number of animals with similar characteristics like those used are a small part of the database of this system. / O presente trabalho foi desenvolvido com os objetivos de avaliar o consumo, a digestibilidade e o desempenho de bovinos mestiços em confinamento alimentados em diferentes frequências de alimentação com dietas contendo diferentes níveis de cálcio e fósforo; determinar suas exigências nutricionais de energia, proteína e macrominerais; e avaliar o efeito da redução do número de amostras destinadas às análises laboratoriais de sobras pelo agrupamento dessas amostras no período total do confinamento, sobre as estimativas de consumo. Foram utilizados 32 animais mestiços 1&#8260;2 Zebu x Holandês, machos, castrados, com peso corporal médio inicial de 377,46±49,4 kg. Inicialmente, quatro animais foram abatidos e tomados como referência para estimar o peso de corpo vazio (PCVZ) inicial dos animais remanescentes no experimento. 24 animais foram distribuídos em delineamento inteiramente casualizado em esquema fatorial 2x3x2, com dois níveis de concentrado (30 e 60%), três frequências de alimentação (alimentação completa fornecida pela manhã, às 8:00 horas; volumoso fornecido em sua totalidade pela manhã e concentrado dividido em duas vezes, às 8:00 e às 16:00 horas; e alimentação volumosa e concentrada dividida em duas porções iguais ao dia) e dietas contendo ou não fontes inorgânicas de cálcio e fósforo. Os outros quatro animais foram alimentados diariamente ao nível de mantença, (1,1% do peso corporal em matéria seca). O volumoso foi a cana de açúcar triturada. Ao final de 84 dias, todos os animais foram abatidos, e a partir das amostras de carcaça e dos constituintes não carcaça foi determinada a composição corporal. No capítulo 1: Os consumos de matéria seca (MS) e dos nutrientes não foram afetados (P>0,05) pelas frequências de alimentação, mas foram superiores (P<0,05) para as dietas com 60% de concentrado. A suplementação com fosfato bicálcico afetou apenas o consumo de fósforo, superior para as dietas suplementadas. Não houve efeito da frequência de alimentação, nem da suplementação com fosfato bicálcico ou das suas interações (P>0,05) sobre as digestibilidades dos constituintes das dietas. Maiores níveis de concentrado proporcionaram maiores ganhos médios diários e rendimentos de carcaça quente e fria. No capitulo 2: As exigências de energia líquida (ELm) e metabolizável para mantença (EMm) foram obtidas relacionando a produção de calor (PC) e o consumo de energia metabolizável (CEM), enquanto as exigências de energia para ganho de peso (ELg) e as exigências líquidas de proteína para ganho foram obtidas em função do PCVZ e do ganho de peso de corpo vazio (GPCVZ). As exigências diárias de energia líquida e metabolizável para mantença foram de 86,48 e 126,15 kcal/PCVZ 0,75, respectivamente. As exigências de energia líquida para ganho podem ser obtidas pela equação: ELg = 0,0568±0,0025 × PCVZ0,75 × GPCVZ1,095. As eficiências de uso da energia metabolizável para mantença e para ganho são de 64 e 29,68%, respectivamente. As exigências de proteína metabolizável para mantença é de 4,14 g/PC0,75. As exigências liquidas de proteína para ganho de peso podem ser obtidas através da equação PLg = 236,36±30,06 × GPCVZ 19,84±6,14 × ER.. No terceiro capítulo: A relação entre o consumo de cada mineral e sua retenção foi expressa a partir de uma equação linear, sendo o intercepto considerado a exigência de mantença do mineral. Nas amostras de carcaça e não carcaça foram determinados a proporção de cada mineral, determinando- se assim o conteúdo corporal para cada um dos minerais, expressos em função do PCVZ. Não foram encontradas variações nas excreções fecal e urinária diárias de fósforo em função da suplementação com fosfato bicálcico. A ausência suplementação de fosfato bicálcico em dietas para bovinos em fase de terminação implica em menor retenção de cálcio e fósforo na carcaça. Os coeficientes de absorção foram de 83,34, 77,21, 82,57, 40,27 e 92,25% para cálcio, fósforo, magnésio sódio e potássio, respectivamente. As exigências líquidas diárias de mantença são de 28,18, 10,31, 50,11, 25,86, e 91,67 mg/PCVZ para cálcio, fósforo, magnésio, sódio e potássio, respectivamente. As exigências líquidas de cálcio, fósforo, magnésio, sódio e potássio para ganho de peso podem ser calculadas respectivamente pelas equações: Ca = GPCVZ × (51,77 × PCVZ-0,3023) ; P = GPCVZ × (30,87 × PCVZ-3459); Mg = GPCVZ × (0,865 × PCVZ-0,2133) ; Na = GPCVZ × (6,517 × PCVZ-0,3483); K = GPCVZ × (4,06 × PCVZ-0,1875). Conclui-se que o consumo, a digestibilidade dos nutrientes e o desempenho não foram afetados pelas frequências de alimentação adotadas nem pelos níveis de cálcio e fósforo, contudo foram melhorados com o aumento do nível de concentrado. Quanto à amostragem de sobras, recomenda-se fazer uma única amostra composta para 84 dias de confinamento. Os valores e equações obtidos para as exigências de animais mestiços Holandês × Gir diferem das obtidas pelo Br-Corte (2010), ressaltando- se que o número de animais com características semelhantes aos utilizados constituem pequena parte do banco de dados desse sistema.
16

Utilization of phosphorus and other minerals from broiler litter and swine waste

Cooke, Judith A. January 1985 (has links)
Two metabolism trials were conducted with 15 wethers surgically equipped with duodenal and ileal cannulas to study the absorption of P and certain other minerals from swine waste and broiler litter. The effect of source and level of P on rumen cellulytic bacterial populations was also determined. Animals were fed a low P basal diet until serum inorganic P averaged 5.5 mg/dl, then randomly assigned to the following diets: low P basal alone, or supplemented with swine waste, broiler litter, dicalcium phosphate, or soybean meal. Trials consisted of a 7-d preliminary period, a 7-d collection of urine and feces and a 6-d sampling of duodenal and ileal digesta, and feces. Animals fed the waste diets tended to absorb more P than those fed the conventional supplements. Calculated by difference, sheep absorbed more P from swine waste and broiler litter than from dicalcium phosphate and soybean meal (P< .1). Less Ca was absorbed from the waste diets than from the conventionally supplemented diets (P< .05). Expressed as g/d, there was no difference in Mg absorption between waste and conventional diets. Sheep fed waste tended to digest more dry matter and a higher percentage of ADF in the large intestine. Lignin was primarily digested in the large intestine of all sheep. More cellulytic bacteria were isolated from the rumen of sheep fed the supplemented diets (P< .05). Both P intake and P recycling appear to be important influences on cellulytic bacteria in the rumen. Both broiler litter and swine waste appear to be good sources of P and Mg for ruminants. / Ph. D.

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