京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第21342号 / 医博第4400号 / 新制||医||1031(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 長船 健二, 教授 羽賀 博典, 教授 妹尾 浩 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Wild pigs are known to be an agricultural pest, but few studies have been done to quantify wild pig damage to corn and the landscape characteristics that are conducive to this damage. In the Mississippi Alluvial Valley, only 15 of the 125 sampled corn fields were damaged (12%). Using yield estimates, input costs and hectares of crop lost, this study concluded that wild pigs cause US$1,753 of damage per hectare. The proportion of corn that was planted within selected buffer scales consistently had a negative effect on whether a field would be damaged. The proportion of soybean planted within the buffer, and the proportion of disturbance had negative impacts on whether a field would be damaged. At multiple buffer scales, the proportion of shrub/scrub, adjacent crops and forest had negative effects on the amount of damage seen in a damaged field.

The active site of porcine kidney microsomal aminopeptidase was investigated using single, multiple and EDTA inactivation kinetic studies. Good inhibitors invariably contained a zinc-coordinating group such as the mercapto moiety, which proved to be the best ligand for aminopeptidase. Due to the potency of β -mercaptoethylamine, derivatives of this compound were examined for aminopeptidase inhibition. (S)-2-amino-4-methyl-l-pentanethiol (L-leucinthiol) exhibited the largest potency and specificity towards aminopeptidase when compared against carboxypeptidase A and thermolysin, two similar zinc-peptidases. The presence of a zinc-coordination subsite, two hydrophobic pocket subsites and a second amine-binding subsite (distinct from that responsible for substrate recognition) were discerned and the binding modes of amino acid hydroxamates and mercaptoamines compared using Yonetani-Theorell inhibition kinetics. Aminopeptidase does not show virtually any stereoselectivity between L-and D-leucine hydroxamate while greater than a 1,000-fold preference is seen for L-leucinthiol over the D isomer. Also, the amino group of mercaptoamines is crucial to the binding of these inhibitors whereas that of the hydroxamate compounds does not seen to contribute much to their binding. The differences in binding between hydroxamates and mercaptoamines are postulated to be a consequence of the product analogue nature of the former and transition state analogue character of the latter. L-leucine hydroxamate is proposed to bind in a backwards orientation while the D isomer binds in the normal substrate-like position. Similarly, L-leucinthiol is proposed to bind in the same fashion as substrate. Design of future inhibitors should endeavour to: (1) lower the pᵏₐ of the α-amino group, (2) include an extended chain structure capable of binding to additional hydrophobic pockets, (3) incorporate a second amine moiety into the structure to interact with the second amine-binding subsite and (4) replace the mercapto group with a more potent zinc ligand such as the selenol group. / Thesis / Master of Science (MSc)

The objective of this study was to evaluate developmental regulation of the expression of nutrient transporter and brushborder hydrolase genes in the small intestine of piglets. Seventy piglets from seven sows were killed at birth (d 0), during suckling (d 1, 3, 7, 14, 21) and postweaning (d 22, 24, 28, 35), and intestinal segments (duodenum, jejunum and ileum) were collected. The mRNA abundance was determined by Northern blot using specific cDNA probes for three disaccharidases (lactase-phlorizin hydrolase, LPH, sucrase-isomaltase, SI, and maltase-glucoamylase, MGA), three peptide hydrolases (aminopeptidase A, APA, aminopeptidase N, APN, and dipeptidyl peptidase IV, DPP IV), two sugar transporters (Na+-dependent glucose transporter 1, SGLT1, and facilitated glucose transporter 5, GLUT5), a peptide transporter (H+-dependent peptide transporter 1, PepT1), four amino acid transporters (excitatory amino acid carrier 1, EAAC1, Na+-dependent neutral amino acid transporter, ATB0, the light chain of a heterodimeric transport system b0,+ involved in the heteroexchange of cationic and neutral amino acids, b0,+AT, and Na+-independent large branched and aromatic neutral amino acid transporter 2, LAT2), and two iron transporters (divalent metal ion transporter 1, DMT1, and iron-regulated transporter 1, IREG1). Protein expression was quantified by Western blot using specific antibodies for LPH, SI, SGLT1, and PepT1. During suckling, the abundance of LPH, APA, APN, DPP IV, b0,+AT mRNA increased quadratically (P < 0.001) with age from birth to d 7 or 14 then remained unchanged or slightly declined with age to d 21. The mRNA abundance of SI increased and LAT2 decreased linearly (P < 0.001) with age, and the abundance of MGA and GLUT5 mRNA remained unchanged with age. There was an age x intestinal segment interaction (P < 0.001) for the abundance of EAAC1 and ATB0 mRNA. The abundance of EAAC1 mRNA increased from d 0 through 14 and remained stable to d 21 in the ileum, and it was low and slightly increased with age through d 21 in the duodenum and jejunum. The abundance of ATB0 mRNA generally increased from d 0 to 21 in the duodenum and ileum, and increased from d 0 to 7 and then decreased to d 21 in the jejunum. The abundance of SGLT1 and PepT1 mRNA was substantial at birth and transiently declined to d 1. The abundance of SGLT1 mRNA generally increased from d 1 to 21, and PepT1 mRNA abundance increased to d 3 and then plateaued through d 21. Postweaning, the mRNA abundance of all of these carbohydrate and protein assimilation related genes increased during the first day (3 d for ATB0) after weaning then declined to the levels at weaning in the jejunum and ileum, followed by a subsequent change pattern that varied among genes. During suckling, the mRNA abundance of LPH, SGLT1, and APA was greater in the duodenum and jejunum than the ileum (P < 0.001). The PepT1 and APN mRNA was evenly distributed among intestinal segments, and the expression of MGA, DPP IV, EAAC1, b0,+AT, ATB0, and LAT2 mRNA was generally greater in the jejunum and ileum than the duodenum or greatest in the ileum. Postweaning, the mRNA abundance of all of these carbohydrate and protein assimilation related genes examined was generally greater in the jejunum and ileum than the duodenum or highest in the ileum. From d 0 through 35, DMT1 and IREG1 mRNA was predominantly (P < 0.05) distributed in the duodenum, where the abundance of DMT1 and IREG1 mRNA increased with age during suckling, and then rapidly decreased after weaning. The protein expression of LPH and SI exhibited a similar developmental pattern as that for the mRNA abundance. Unlike the developmental regulation of their respective mRNA abundance, the protein expression of SGLT1 exhibited a general decline from suckling to postweaning. The protein expression of PepT1 gradually decreased with age from birth to d 35 in the duodenum, and initially declined from birth to the lowest value then slightly increased with age through d 21, followed by an increase to d 35 in the jejunum and ileum. In conclusion, the gene expression of these brushborder hydrolases and nutrient transporters was not only differentially regulated by age but also differentially distributed along the small intestine of piglets at early stages of life. These differences in ontogenetic regulation and the distribution may be related to the luminal substrate concentration as well as the nutrient categories, and the developmental regulation of these genes may occur not only at the transcriptional level but also at the posttranscriptional level. / Ph. D.

This study was conducted to investigate the efficacy of phytase for improving the nutrient utilization for pigs and poultry. Two experiments, one with broilers and one with pigs, were conducted to compare the efficiency of transgenic microbial (Natuphosà ) and plant (Phytaseedà ) phytase for enhancing the utilization of phytate P in corn-soybean diets fed to young broilers and pigs, and to evaluate the safety of Phytaseedà phytase. Three levels of the two sources of phytase (250, 500 and 2,500 U/kg of diet) were added to a corn-soybean meal basal diet containing 0.21 and 0.26% nonphytate P, respectively, for broilers and pigs. Forty birds and thirty pigs (8 broilers and 6 pigs, one per cage, from the diet without added phytase and the diets with 500 or 2,500 U/kg phytase from both sources) were randomly selected for gross necropsy and histologic evaluation of liver, kidney and bone tissues. Adding both sources of phytase to the basal diet resulted in similar increases of BW, BW gain, feed intake, gain:feed, apparent digestibilities (retention) of DM, P and Ca, and bone measurements. Phosphorus excretion decreased as phytase addition increased. No significant abnormalities were seen in any of the broilers and pigs necropsied. In a study with pigs (n=120 and 80, respectively for grower and finisher), the effects of supplemental microbial phytase on crude protein and amino acid utilization of low protein plant-based diets was investigated. During the grower period (32 to 67 kg), diets 1, 2 and 3 contained 14, 13 and 12% crude protein and no added phytase, respectively, and diets 4 and 5 contained 12% crude protein with either 250 or 500 U of phytase/kg of diet, respectively. During the finisher period (67 to 109 kg), diets 1, 2 and 3 contained 12, 11 and 10% crude protein with no added phytase, respectively, and diets 4 and 5 contained 10% crude protein with either 250 or 500 U of phytase/kg of diet, respectively. At the end of grower phase, two pigs (1 barrow and 1 gilt) were removed from each pen; 12 of the barrows that were removed from diets 1, 3 and 5 were put in metabolism cages for total collection, and the remaining four pigs in each pen continued on test for the finisher phase. At the end of finisher phase, 12 barrows from diet 1, 3, and 5 were put in metabolism cages for total collection. Ileal contents were taken (slaughter technique) from the remaining barrows and the barrows used in metabolism cages. Daily gain increased as protein and phytase levels was added to the lowest protein level. Fecal P and Ca digestibilities improved with added phytase. Phytase addition to basal diet linearly increased ash weight in the grower phase. With the exception of proline and glycine, the digestibilities of the other amino acids were linearly increased with phytase and CP level. Nitrogen excretion was estimated to be reduced by 4.6% when phytase was added to pig diets at a level of 500 U/kg. In a study with cecectomized roosters, the main effects and interaction of phytase and non-startch polysaccharide enzymes on the nutrient utilization of barley, canola meal, rice bran and soybean meal, and canola-barley (36:64) and soybean meal-barley (27.3:72.7) were evaluated. Phytase supplementation to basal diets increased the utilization of energy, N, total amino acid and most of amino acids in barley, canola meal, and canola-barley and numerically increased energy and N utilization in rice brain, soybean meal and soybean-barley. The magnitudes of improvements in the digestibilities of lysine, arginine, cysteine, serine, and threonine were higher compared with the other amino acids. The true utilization of energy and N, and the digestibilities of total amino acid and of glycine, isoleucine, and histidine in barley quadratically increased with Ronozyme™ B. Phytase addition increased Ca retention in barley, canola and soybean meal, and the soybean meal-barley blend, and increased P retention in barley and soybean meal-barley. Addition of Ronozyme™ B to barley linearly decreased Ca retention and quadratically increased P retention. In summary, the efficiency of phytase in Phytaseed is equal to that of Natuphos for enhancing the utilization of phytate P in corn-soybean diets, and microbial phytase is effective in improving the utilization of N and amino acid in pigs and N, amino acid, and energy in poultry. / Ph. D.

Intrauterine growth restriction causes impaired growth and development of mammalian fetus, and leads to long-term negative effect on postnatal growth. Among domestic animals, pigs exhibit the most severe naturally occurring IUGR and reduced postnatal muscle growth. The objectives of this research project were to: 1) determine muscle stem cell characteristics in IUGR pigs; 2) determine how intrauterine growth restriction alters protein deposition in skeletal muscle; 3) investigate whether branched-chain amino acids (BCAA) are able to enhance protein synthesis in intrauterine growth restricted (IUGR) pig muscle. Newborn piglets were considered normal body weight (NBWT) or IUGR when birth weight was within ± 0.5 SD and -2 SD of litter average respectively. Muscle satellite cell numbers, believed to be the major nuclei source for postnatal muscle growth, were lower in newborn IUGR pigs which could result in reduced muscle hypertrophy potential. In addition, cultures derived from IUGR muscle satellite cells had a lower fusion percentage. Fewer satellite cells and impaired differentiation ability may contributor to impaired muscle growth in these pigs. Protein synthesis rate was significantly lower in IUGR pig hindquarter in the first hour after feeding, but BCAA supplementation had no effect on protein synthesis in IUGR pigs. Further, eukaryotic translation initiation factor 4E (eIF4E) expression is down regulated in IUGR pig muscle. These results suggest that impaired translation initiation may provide a plausible explanation for the lower protein synthesis rates observed in IUGR pigs. Overall, reduced muscle stem cell number and changes in their activity, as well as impaired translation initiation may be important explanations for compromised postnatal muscle growth in intrauterine growth restricted pigs. / Ph. D.

Distillers dried grains with solubles (DDGS) is a byproduct of distillation. Its increased availability has led to research into overcoming the nutritional limitations of its high non-starch polysaccharide (NSP) content for use in monogastric animal feed. The purpose of this study was to examine the effects of two factors (the inclusion of DDGS and/or inclusion of a carbohydrase mixture) on the richness and abundance of swine gastrointestinal bacteria. The carbohydrase mixture was expected to aid digestion, leading to increased nutritional availability for the host while simultaneously shifting dominant communities within the gut microbiome. Ileal cannulated pigs (n = 8, BW = 64.3 +/-0.5 kg) were allotted to 4 dietary treatments in a replicated 4 x 4 Latin square design. Treatments resulted in changes to bacterial richness, and diets containing DDGS increased the 16S rDNA abundance of members of Bacteroides (P < 0.0001), Ruminococcus (P < 0.0001), the Clostridium coccoides group (P <0.0001), and the Clostridium leptum subgroup (P = 0.005). Significant interactions between diet and carbohydrases were determined for total bacteria in the ileal digesta (P = 0.01) and feces (P = 0.02), Bacteroides (P = 0.003), and the Clostrdium leptum subgroup (P = 0.03). The DDGS diet with the inclusion of the carbohydrases was able to maintain, or increase the abundance of fiber degrading bacteria while theoretically increasing nutrition for the host. / Master of Science in Life Sciences

Master of Science / Department of Animal Sciences and Industry / Joel DeRouchey / Seven experiments using a total of 2,997 nursery and finishing pigs were used to determine the effects of: 1) dietary wheat middlings (midds), dried distillers grains with solubles (DDGS), and NE diet formulation on nursery pig growth performance; 2) corn particle size, complete diet grinding, and diet form on finishing pig growth performance, and carcass characteristics, and 3) particle size, complete diet grinding, and diet form on nursery pig growth. Experiments 1-4 evaluated dietary wheat middlings at levels of up to 20% of the diet for 7 to 23 kg pigs. Increasing dietary midds decreased growth performance but mainly when 10% of more was added. Balancing diets containing 10 or 20% midds on a NE basis had no significant effects on performance compared with not adjusting for NE of the diet. In Exp. 5, the effects of decreasing particle size, complete diet grinding, and diet form were evaluated on finishing pig growth performance, and carcass characteristics. Diet form × portion ground interactions existed for ADG, ADFI, and HCW as grinding the complete diet in meal form was detrimental to performance but advantageous to performance when diets were fed in pelleted form. Reducing the particle size of corn improved G:F and caloric efficiencies. Pelleting the diet improved ADG, G:F, caloric efficiencies, HCW, and loin depth. Experiment 6 evaluated varying particle sizes, diet form, and complete diet grinding on nursery pig growth performance. Pigs fed pelleted diets had improved ADG, G:F, and caloric efficiencies. Fine grinding corn or the complete diet with high by-products diet decreased ADG, ADFI, G:F, and final BW. Experiment 7 evaluated varying particle sizes of corn and DDGS, diet form, and complete diet grinding on nursery pig growth performance. Pigs fed finely ground corn had decreased ADFI when the diet was fed in pellet form and more severe reductions in ADFI when diets were fed in meal form resulting in a diet form × corn particle size interaction. Pigs fed pelleted diets had decreased ADG, ADFI, G:F and final BW, but improved caloric efficiencies. Finely grinding corn decreased ADG, and feeding DDGS decreased ADG, ADFI, and NE caloric efficiency.

[pt] Neste trabalho apresenta-se a avaliação do desempenho de ferramentas de inspeção em linha (ILI) ou pig instrumentado na medição de defeitos causados por corrosão e estudam-se diferentes métodos para o cálculo da confiabilidade estrutural ou cálculo da probabilidade de falha (POF) de um duto corroído, baseada na análise do relatório do pig. O relatório de inspeção do pig é avaliado através de comparações de seus resultados com as medições dos defeitos feitas por ferramentas de referência (medições em campo). Os erros associados a cada sistema de medição podem ser encontrados a partir de métodos estatísticos como os métodos da raiz do erro quadrático médio, dos estimadores de Grubbs, de Thompson e de Jaech. As medições das duas ferramentas são também avaliadas através de testes estatísticos para a linha de tendência e o coeficiente de correlação linear (r). O número mínimo de medições de campo necessárias para verificar o desempenho do pig no dimensionamento dos defeitos de corrosão é determinado pela implementação de um teste baseado na análise seqüencial. Uma vez que o relatório do pig é avaliado e aceito, a POF de um duto corroído é calculada usando os métodos analíticos de primeira ordem (FORM) e propagação de incertezas, e o método de simulação de Monte Carlo. A POF do duto é calculada em função de modelos de pressão de falha onde suas variáveis são definidas como funções de probabilidade (fdp). No caso das dimensões do defeito, a fdp e seus parâmetros estatísticos são obtidos a partir da exatidão do pig. A comparação entre a POF calculada e a POF admissível permite determinar quando será necessário fazer uma nova re-inspeção. Quando a POF calculada atinge um valor maior que a POF admissível, antes de se completar um tempo desejado para a próxima inspeção, o procedimento desenvolvido permite decidir qual o número de reparos que deverá ser feito para que este tempo seja alcançado. / [en] This work presents: i) the assessment of in line inspection (ILI) tools performance in the measurement of defects caused by corrosion; ii) differents methods to calculate structural reliability and probability of failure (POF) of corroded pipeline based in the ILI report. The inspection report of the ILI (or instrumented pig) is compared with the the geometry of defects measured by a reference tool (field measurements) and the erros associated to each measurement system are analyzed and assessed from statistical methods. The statistical analysis emploies methods such as the root mean square error/diffrential, and the Grubbs s, Thompson s and Jaech s estimators. The measurements taken by both tools (pig and field) are compared and analyzed through statistical tests that consider the tendency line and the coefficient of linear correlation (r). The minimum number of field measurements necessary to verify the performance of the ILI in sizing of corrosion defects is determined by the implementation of a test based on the sequential analysis. POF of a pipeline is calculated using three different methods: i) first order reliability methods (FORM); ii) propagation of uncertainties and iii) the method Monte Carlo. The POF of the pipeline is calculated as a function of different failure models whose variables (such as pressure, geometric and material parameters) are defined by their probability functions (pdf). The pdf and statistical parameters of the defect dimensions are determined from the accuracy of the pig measurements. The comparison between calculated and acceptable POF allows the determination of next reinspection period. When the calculated POF exceeds the acceptable POF before completing the amount of time desired for the next inspection, the developed procedure allows to know the number of repairs that must be made to reach the desired time when the next ILI will be carried out.

No description available.