京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第20427号 / 農博第2212号 / 新制||農||1048(附属図書館) / 学位論文||H29||N5048(農学部図書室) / 京都大学大学院農学研究科応用生物科学専攻 / (主査)准教授 谷口 幸雄, 教授 今井 裕, 教授 廣岡 博之 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

Dietary inclusion of sufficient lysine is very critical for optimizing pig’s growth performance. The objectives of this project were to study the effects of dietary lysine at different concentrations on (1) the growth performance and carcass characteristics, (2) the muscle gene expression profile and the possible alterations to the metabolic and signaling pathways, (3) the muscle fatty acid profile, and (4) the plasma concentrations of growth-related hormones of late-stage finishing pigs. Nine crossbred barrows were assigned to 3 dietary treatments (lysine-deficient, equate, and -excess diets) according to a completely randomized experimental design. During the 5-week feeding trial, pigs were allowed ad libitum access to experimental diets and water. All pigs and experimental diets were weighed individually each week during feeding trial to determine growth performance. After harvest, the carcass characteristics were determined and muscle samples were collected from longissimus dorsi for mRNA and fatty acid profiling, while the jugular vein blood was collected at the end of four weeks for analyses of three growth-related hormones. While the average daily gain showed a quadratic relationship, the dressing percentage and total lean cut weight both increased linearly with dietary lysine concentrations. Results of muscle gene expression data showed that dietary lysine deficiency may lead to decreased protein synthesis, increased protein degradation and lipid accumulation, while dietary lysine excess may lead to decreased protein degradation and increased lipid biosynthesis. Fatty acid (FA) composition data showed that different dietary lysine concentrations altered the intramuscular fat (IMF) content and FA composition, especially the unsaturated FAs. In particular, dietary lysine deficiency increased the IMF content and the proportion of mono-unsaturated FAs. Hormone analyses showed that the plasma concentrations of insulin and growth hormone were not affected by dietary lysine, whereas the concentration of insulin-like growth factor 1 was decreased by either dietary lysine deficiency or excess. Collectively, lysine may function as a signaling molecule to regulate the expression of genes related to protein turnover and lipid metabolism in the muscle of finishing pigs, causing differences in growth performance, carcass characteristics, and FA composition. IGF-1 may be a controlling growth factor that is sensitive to dietary lysine.

The objective of this study was to determine the effects of feeding endophyte-infected tall fescue seed to Angus steers on average daily gain, carcass characteristics, ergovaline concentration, lipid oxidation, hepatic enzyme activity, metmyoglobin reductase activity, and mitochondrial lipid composition. Animals were blocked into light, medium, and heavy body weight groups and were randomly assigned to either a KY31 seed treatment (6796 ppb ergovaline; 20 MUg/kg BW; E+; n = 6) or a KY32 control (< 100 ppb; E-; n = 6). There was a 2-way treatment × time interaction effect on ADG (P < 0.001). The E+ steers gained 0.56 kg/d less than the E- steers from d 0 to 14 (P < 0.001) until d 56 (ADG difference = 0.27 kg/d; P = 0.007) but both group had similar ADG from d 70 till the end of the feeding period 2 (ADG = 0.53 kg/d; P > 0.070). No difference in carcass characteristics were found between the E+ and E- steers by at the time of ultrasonography (P >= 0.120) or at harvest (P >= 0.199). In both period 1 and 2, there was a 2-way treatment × time interaction for ergovaline concentration in blood (P = 0.002 and 0.022, respectively). Infected tall fescue seed did not change d-3 hepatic enzyme activity in both feeding periods (P = 0.149 to 0.645). In period 1, thiobarbituric acid reactive substances, primarily consisting of malondialdehyde (MDA), were greater in blood serum of E+ steers than E- steers (6.56 MUM vs. 2.56 MUM; P = 0.048). An overall increase in MDA from d 0 (2.39 MUM) to d 3 (7.59 MUM) was also observed (P = 0.049). There was no effect of endophyte infected tall fescue seed on metmyoglobin reductase in longissimus thoracis (4.82 MUM/min/g in E- muscle vs. 3.93 MUM/min/g in E+ muscle; P = 0.484. There was no treatment effect on mitochondrial lipid composition (P >= 0.094), including phospholipids and fatty acids.

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No description available.

The objective of the present thesis was to study the effect of the selection for growth rate on the carcass and meat quality of line R, which is a line of rabbits selected for growth rate between the 4th and 9th week of age. This line is usually used in breeding schemes, where males from line R are mated with crossbreed females from two lines selected for litter size. When the line R was in the 7th generation of selection some embryos were recovered and vitrified. The selection of the line continued and the embryos were devitrified after some generations. The offspring of the rabbits obtained from the embryos formed the control group (Group C). This group was contemporary compared with the selected group (Group S), formed with rabbits from the present generation of selection. With groups S and C, two experiments were developed. The first experiment consisted in the study of the effect of selection for growth rate on the relative growth of offal, organs, tissues, carcass linear measurements and weight of several parts of the carcass. Group C was contemporary compared with Group S, formed with animals from the 18th generation of selection. A total of 313 animals from both groups and sexes were slaughtered at 4, 9, 13, 20, and 40 weeks old. Organs, tissues and retail cuts were weighed and several carcass linear measurements were recorded. Huxley's allometric equations relating the traits to liveweight by a parameter related to the scale (b) and an allometric coefficient (k) were fitted. Butterfield's quadratic equations relating the degree of maturity of the traits and the degree of maturity of the liveweight by an allometric coefficient (q) were also fitted. Values obtained for k and q coefficients led to similar patterns of growth in most of the traits studied. Full gastrointestinal tract and organs such as liver, kidneys, and thoracic viscera were early maturing (k<1 or q>1) whereas the chilled and reference carcass where late maturing (k>1 or q<1). The re / Pascual Amorós, MDLD. (2007). Effect of selection for growth rate on carcass composition and meat quality in rabbits [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/1938

En esta tesis se aborda el estudio de la grasa intramuscular como característica determinante de la calidad de la carne para ser utilizado en programas genéticos. El conejo se plantea no sólo por su interés como especie ganadera sino como modelo en otras especies. Este estudio se divide en tres experimentos, cada uno de ellos representa cada uno de los tres objetivos específicos de esta tesis: 1. Estudiar la variabilidad genética entre líneas de conejo de factores ligados directamente a la deposición de grasa tanto en músculo como en tejido adiposo, como son las enzimas que participan en la síntesis y degradación de la grasa y en la composición en ácidos grasos. 2. Puesta a punto de una calibración NIRS para estimar grasa intramuscular y la evaluación de su uso en programas de selección en conejo. 3. Selección divergente por grasa intramuscular. Estudio de las posibilidades de éxito de la selección por grasa intramuscular y conocer las relaciones genéticas entre caracteres examinando la respuesta correlacionada. Supone el inicio de una nueva línea de investigación en metabolismo lipídico, que puede servir tanto a la producción de conejo como animal de carne como al uso del conejo como modelo experimental. Es la primera vez que se propone un experimento de selección divergente por grasa intramuscular. Este experimento permitirá conocer mejor las relaciones genéticas entre la grasa intramuscular, la grasa de la canal, así como las relaciones con otros caracteres productivos. El conocimiento de estas relaciones genéticas va a ser fundamental para futuros programas de mejora genética en todas las especies ganaderas. / Zomeño, C. (2013). ANÁLISIS GENÉTICO DE LA GRASA INTRAMUSCULAR EN CONEJO-GENETIC ANALISYS OF INTRAMUSCULAR FAT IN RABBITS [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/31121

The taphonomy and paleoecology of a well-preserved mosasaur (DSM 10716) are reported from Oktibbeha County, Mississippi. The mosasaur was recovered from the Prairie Bluff Chalk, the exact stratigraphic position and age confirmed using established foraminiferal zonation for the Late Cretaceous of the U. S. Gulf Coastal Plain. A species identification of Mosasaurus cf. hoffmanni Mantell is given using shape and structure of the quadrate and jugal, as well as tooth counts for the dentary, maxilla, and pterygoid. DSM 10716 exhibits well-preserved trace fossils including feeding traces and the remains of encrusting bivalves. The associated fossils are probed for similar phenomena to modern whale falls and other ancient carcass falls. Based on associated fossils present on DSM 10716, evidence for a mobile scavenger stage, a possible enrichment opportunist stage, and a reef stage is established. No chemosynthetic organisms were detected to suggest the existence of a sulfophilic stage.

Master of Science / Department of Animal Sciences and Industry / Terry A. Houser / Two experiments were conducted to determine the effects of dried distillers grains with solubles (DDGS) on pork loin and fat quality. In the first experiment, 1,160 barrows (PIC) were used in a 70-d study to determine the influence of DDGS and glycerol on pork loin and fat quality attributes. Barrows were fed a corn-soybean meal based diet with the addition of selected levels of DDGS (0 or 20%) and glycerol (0, 2.5, or 5%) feed stuffs. Loins from the two heaviest pigs in each pen were removed for evaluation of pork loin and fat quality. Experiment two was a pilot study, in which eight non-pregnant sows were fed either 0 or 50% DDGS with a corn soybean meal based diet for 92-d. In the first experiment, there were no DDGS x glycerol interactions for purge loss %, instrumental color (L*a*b*), visual color, marbling score, drip loss %, visual color, pH, Warner-Bratzler shear force (WBSF), cook loss %, myofibrillar tenderness, juiciness, pork flavor intensity, connective tissue amount, and overall tenderness. There was a DDGS x glycerol interaction (P<0.03) for off-flavor intensity. Pigs fed diets with 20% DDGS had higher WBSF values, lower myofibrillar tenderness, lower overall tenderness scores, lower connective tissue scores, and had more off-flavors (P<0.05). Loin fatty acid analysis revealed an increase in palmitoleic, linoleic, and eicosadienoic acids (P<0.05) and iodine value (P<0.03) for pigs fed 20% DDGS. In the second experiment, there were no differences (P>0.64) in BW or backfat change for sows fed either 0 or 50% DDGS. No differences (P>0.23) in lipid oxidation from lean trimmings as measured by 2-thiobarbituric acid reactive substances (TBARS) assay were reported either initially or after 5 d of retail display for sows fed either 0 or 50% DDGS. As expected, lipid oxidation increased (P<0.003) as measured by TBARS assay for both treatments from d 1 to 5. Jowl fatty acid analysis revealed an increase in linoleic acid (P<0.01), total polyunsaturated fatty acids (P<0.01), and the ratio of polyunsaturated fatty acids to saturated fatty acids (P<0.03) for sows fed 50% DDGS.

Master of Science / Department of Animal Sciences and Industry / James S. Drouillard / A trial was conducted replacing portions of steam-flaked corn with either dry-rolled corn or dried distiller’s grains with solubles to evaluate effects on performance, carcass characteristics, carcass composition, meat color stability, and meat sensory attributes. Seven hundred crossbred yearling heifers (302 ± 65 kg initial BW) were used in a randomized complete block experiment with a 2 x 2 factorial arrangement of treatments. All diets contained steam-flaked corn (SFC), and factors consisted of the levels of dry-rolled corn (DRC; 0 or 25%) and dried corn distiller’s grains with solubles (DDGS; 0 or 25%). Results revealed no interactions between DRC and DDGS in terms of effects on feedlot performance, and only minor interactive effects were observed for carcass characteristics and meat quality attributes. Feedlot performance and carcass characteristics were not affected by the addition of DRC or DDGS (P > 0.05). Carcass composition and meat quality attributes were measured to determine if fat content of carcasses was altered by feeding DDGS. Diet had no significant effects, as carcasses from the four treatments contained similar amounts of separable portions of muscle, adipose, and bone; and similar percentages of protein, moisture, and ether extract. Compositions of both adipose and muscle tissue were evaluated to assess differences in fatty acid profile. Minimal effects were noted on the fatty acid profiles of the muscle and adipose tissue from cattle fed DDGS or DRC. Feeding cattle DDGS decreased alpha tocopherol (vitamin E) content of meat (P < 0.05). Meat quality attributes were largely unaffected by addition of DRC or DDGS to the diet, as retail color display life, lipid oxidation, sensory attributes, and heterocyclic amine concentrations were not different among treatments. Overall, DRC or DDGS can replace portions of SFC without negatively altering feedlot performance, carcass characteristics, meat composition, or meat quality attributes.