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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.
431

The evaluation of sorghum dried distiller's grains with solubles in nursery pig diets, on finishing pig performance and meat quality, and on lactating sow performance.

Sotak, Kelly Marie January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Robert Goodband / Five experiments were conducted to determine the effects of sorghum dried distiller’s grains with solubles (DDGS) on nursery pig performance, finishing pig performance and meat quality, and lactating sow and litter performance. Experiment 1 established a nutrient database and evaluated the quality and consistency of five ethanol plants in the Western Plains region. Each sample was analyzed for AA, DM, CP, crude fiber, crude fat, ash, NDF, ADF, Ca, P, trace minerals, GE, and starch. In addition, DE, ME, and NE were calculated. Experiments 2 and 3 evaluated the effects of sorghum DDGS on nursery pig performance. In Exp. 2, pigs fed sorghum- or corn-based diets performed similarly; however, as sorghum DDGS increased ADG decreased (linear, P < 0.01). A DDGS×grain source interaction (quadratic, P = 0.03) was observed for G:F. In corn-based diets, G:F was identical for pigs fed 0 to 30% DDGS, but worsened in pigs fed 45% DDGS. In sorghum-based diets, G:F was best for those fed 0% DDGS, but worsened at higher levels. In Exp. 3, pigs fed corn- or sorghum-based diets performed similarly; however, pigs fed DDGS gained less (P < 0.03) than those fed basal diets. Experiment 4 evaluated the effects of sorghum DDGS in sorghum- or corn-based diets on finishing pig growth performance, carcass characteristics, and fat quality. Increasing sorghum DDGS reduced (linear; P < 0.01) ADG and increased (linear; P < 0.01) backfat IV. Pigs fed the sorghum-based diet with 30% sorghum DDGS had decreased backfat IV (P < 0.01) than those fed the sorghum-based diet with corn DDGS. Experiment 5 evaluated the effects of sorghum DDGS on lactating sow and litter performance. Overall, ADFI increased in corn-based diets when DDGS were added, but decreased in sorghum-based diets resulting in a tendency (P < 0.08) for a DDGS × grain source interaction. Pig weaning weights were lower (P < 0.06) for sows fed diets containing DDGS compared with those fed the basal diets. Adding sorghum DDGS reduced pig performance, and sow lactation performance; therefore, its inclusion in swine diets needs to be evaluated on an income over feed cost basis.
432

Influence of management factors on reproduction in beef cattle: 1. Effects of melengestrol acetate and growth promoting implants on oocyte quality and subsequent in vitro embryo development 2. Exposure of prepubertal beef bulls to cycling females to enhance sexual development

Miller, Natalie Ann January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Karol E. Fike / This thesis involves two separate studies that evaluate the effects of different beef cattle management practices on reproduction. The objective of the first study was to determine if feedlot heifers administered melengestrol acetate (MGA) and growth promoting implants could serve as viable oocyte donors for in vitro embryo production. Ovaries from heifers administered MGA and growth promotants (MGA-Implant) and ovaries from heifers not administered either substance (Control) were collected from heifers post-slaughter. Oocytes were harvested and in vitro maturation, in vitro fertilization (IVF), and in vitro culture were completed. Treatment and time interacted to affect the number of oocytes aspirated per ovary (P = 0.07) and the number of zygotes per ovary (P = 0.07). Fertilization (P = 0.90) and cleavage rates (P = 0.80) did not differ between treatments. Blastocyst rates (P = 0.30) and the number of embryos per ovary (P = 0.50) did not differ between treatments. We concluded that beef feedlot heifers fed MGA and implanted with growth promotants seem to be a viable source of oocytes for in vitro embryo production. In the second study, we hypothesized that continuous fenceline exposure of prepubertal beef bulls to cycling beef females would hasten the onset of puberty as well as increase the percentage of bulls passing their initial breeding soundness examination (BSE). Bulls were either exposed to estrous females (exposed) or were not exposed (control). Monthly scrotal circumference (SC) measurements, blood samples, semen evaluations, and bull behavior assessments were conducted. Age at puberty (P = 0.40), SC at puberty (P = 0.50), and weight at puberty (P = 0.30) did not differ between treatments. A similar (P = 0.50) percentage of bulls passed their initial BSE at 363 ± 21.5 d of age (exposed: 87.8%; control: 74.2%). Treatment, month, and stage of the estrous cycle of cows interacted to affect the number of mount attempts (P = 0.05) and the number of flehmen responses (P < 0.001). In conclusion, bulls given continuous fenceline exposure to cycling beef females were neither younger at puberty nor did a greater percentage pass their initial BSE.
433

Estimation of genetic parameters for udder quality in Hereford cattle

Bradford, Heather Lynn January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Daniel W. Moser / Udder quality is an important trait for beef producers because udders impact cow longevity and calf performance. The objective of this study was to estimate the genetic parameters for udder quality in Hereford cattle. The Beef Improvement Federation recommends collecting subjective scores on udder suspension and teat size. Prior to these guidelines, the American Hereford Association (AHA) recorded an overall score, which combines all udder characteristics into a single score. In all cases, scores ranged from 1 to 9 with a score of 9 considered ideal. Records on 78,556 animals and a 3-generation pedigree with 196,540 animals were obtained from the AHA, Kansas City, MO. These records contained repeated observations for overall score (n=126,753), suspension (n=61,758), and teat size (n=61,765). Data were modeled using a multiple trait animal mixed model with random effects of additive genetic and permanent environment and with fixed effects of age and contemporary group (herd-year-season). Variances were estimated with ASREML 3.0. Heritability estimates (standard errors) of overall score, suspension, and teat size were 0.32 (0.01), 0.31 (0.01), and 0.28 (0.01), respectively. These results showed udder quality was moderately heritable, agreeing with previous research. The phenotypic correlation (standard error) between teat size and suspension was 0.64 (0.003). Of the records for suspension and teat size, 57% had the same score for both traits. The genetic correlations (standard errors) between teat size and suspension, overall score and teat size, and overall score and suspension were 0.83 (0.01), 0.72 (0.02), and 0.70 (0.02), respectively. The genetic correlations between traits were extremely strong. In addition, producer education is important to ensure the scoring systems are used correctly.
434

Development and Characterization of Microsatellite Markers for the Grain Amaranths (Amaranthus spp. L.)

Mallory, Melanie Ann 13 July 2007 (has links)
The grain amaranths (Amaranthus hypochondriacus L., A. cruentus L., and A. caudatus L.) are important pseudocereals native to the Americas that have received increased attention for their nutritional content, specifically their balance of amino acids. The objective of this project was to produce and characterize a set of highly informative, reproducible microsatellite markers for the grain amaranths. A total of 1457 clones were sequenced from three genomic libraries enriched for the microsatellite motifs AAC, AAT and AC. Of these, 353 (24%) contained unique microsatellites. An additional 29 microsatellite loci were identified among 728 BAC-end sequences of a newly developed amaranth BAC library. Flanking primers were designed for 319 of the microsatellite loci and all were screened on a panel of diverse amaranths, including grain and weedy Amaranthus species. A total of 179 (56%) microsatellites were polymorphic across accessions from the three grain amaranths. Among these polymorphic microsatellite loci, a total of 731 alleles were identified with average of four alleles per locus. Heterozygosity values ranged from 0.14 to 0.83 with a mean value of 0.62. Thirty-seven (21%) of the markers were polymorphic between the parents of a segregating population and were shown to be inherited in a normal Mendelian fashion based on chi-squared analysis, demonstrating the utility of these markers for linkage mapping of the amaranth genome. Phylogenetic analysis using the marker data showed A. hybridus accessions in two of the three major grain amaranth clades, suggesting the polyphyletic evolution of the three cultivated species from different A. hybridus ancestors. The microsatellite markers reported here will be useful for further evaluating the relationships among the grain amaranths and their relatives and are an ideal resource for use in marker-assisted breeding programs, germplasm analysis and varietal identification. The transferability of these markers to A. hybridus, A. powellii, and A. retroflexus as reported here suggests that the markers may be useful to other species with the genus Amaranthus, including economically important weeds, vegetable amaranths, and ornamentals.
435

Local Distribution in a Population of Uinta Ground Squirrels

Walker, Robert Edgar 01 May 1968 (has links)
In an attempt to describe, explain, and show the demographic significance of annual variations in the nesting distribution of Uinta ground squirrels, a study was conducted during the summers of 1964 through 1967 in northern Utah. Procedures included both trapping and direct observation. It was found that females tended to nest in open, previously inhabited, grassy areas. Males resided throughout a variety of habitats. This typical nesting distribution was established initially in the summer by juveniles shortly after they first appeared aboveground. The extent to which the distribution was maintained the following spring depended largely upon the number of female s which emerged from hibernation and the pattern in which they emerged. The number of females which appeared depended upon the previous year's breeding density and productivity. The pattern of emergence appeared to be a function of an inherent pattern of physiological arousal from hibernation and the prevailing weather conditions. The number and sequence of emergence of females in the early spring affected breeding and social organization in a manner which limited the number of females which retained residences in the study area. This determined the actual breeding density. In addition, emergence influenced the production of offspring by altering both the breeding density and the number of non-productive females in the population. The adaptive significance of the system and its applicability to other species are discussed.
436

Effects of Cache Valley Particulate Matter on Human Lung Cells

Watterson, Todd L. 01 May 2012 (has links)
During wintertime temperature inversion episodes the concentrations of particulate air pollution, also defined as particulate matter (PM), in Utah’s Cache Valley have often been highest in the nation, with concentrations surpassing more populated and industrial areas. This has attracted much local and national attention to the area and its pollution. The Cache Valley has recently been declared to be in non-attainment of provisions of Federal law bringing to bear Federal regulatory attention as well. While there is epidemiological evidence indicating that PM is detrimental to public health, there is much less information indicating by which biological and molecular mechanisms PM can exert harm. This study was undertaken to better understand the mechanisms by which ambient PM collected in the Cache Valley can be harmful to human lung cells. Cache Valley PM was found to be mildly cytotoxic only at concentrations that were much greater than physiologically achievable, and such concentrations were difficult to obtain with the limited amounts of captured ambient PM. The limited cytotoxicity was despite apparent PM-induced pro-apoptotic signaling such as caspase-3 upregulation, and activation of caspase-12 and calpain. Cache Valley PM was found to be stressful to cells, triggering endoplasmic reticulum stress and the unfolded protein response. Cache Valley PM was also found to be inflammogenic leading to activation of pro-inflammatory transcription factors, increases in the release of pro-inflammatory cytokines and chemokines, as well as the upregulation of the activating receptors of these cytokines. The proinflammatory effects and absence of apoptosis, despite pro-apoptotic signaling of the Cache Valley PM on human lung cells appeared to stem from increased activation of the central pro-growth protein Akt with subsequent inactivation of the tumor suppressor P-TEN. These findings have indicated novel mechanisms of PM-related cellular stress and inflammation contributing needed information on what may be underlying mechanisms of PM associcated illnesses.
437

Ambient Temperature, Calf Intakes, and Weight Gains on Preweaned Dairy Calves

Holt, Sheldon D 01 May 2014 (has links)
There has been little research conducted on the physiological response of calves to temperatures outside thermal neutrality and its effects on intake and weight gain. The effects of ambient temperature on Holstein dairy calves intakes and weight gain were evaluated over a 12-month period. Ambient temperature was monitored using a weather station located 1.3 kilometers from the Utah State University Caine Dairy. Calf health was monitored daily using the University of Wisconsin-Madison School of Veterinary Medicine scoring criteria. Calves were fed whole milk and free choice calf starter. Weight gain, hip height, starter intake, and weather data (temperature, wind speed, relative humidity, precipitation, and barometric pressure) were averaged for 7-day intervals beginning at birth through 13 weeks of age. A regression model was developed including starter intake, milk intake, hip and wither height, calf heath scores, and weather data with weight gain as the dependent variable for each of the 4 seasons of the year. The fall season (September, October, and November) had a negative impact on calf intake and weight gain (averaging 20 pounds (9.1 kilograms) less at 2 months) than other seasons. Calves raised in the winter months also ate significantly more starter, but had the same weight gain as other seasons. Environmental stress factors impact animal welfare and animal productivity, which in turn impacts the economics of the dairy operation and should also be used in determining husbandry practices.
438

Use of Soybean Meal, Raw Soybeans, & Heat-Treated Soybeans as Protein Supplements with & without Niacin for Dairy Cows in Early Lactation

Aguilar, Daniel 01 December 1987 (has links)
Twenty three cows with an average of 2.7 lactations were used to measure the effects of different protein sources (soybean meal, soybeans, and heat-treated soybean) and supplementation with niacin on milk production, milk components (protein, fat, somatic cell counts), 4% fat corrected milk, solid corrected milk, dry matter intake, body weight changes, and rumen volatile fatty acids (acetate, propionate, butyrate). Diets affected performance of cows. The results indicate, in general, that feeding heat-treated soybean and soybean meal to lactating dairy cows in early lactation resulted in greater milk production, milk protein, dry matter intake and less loss of body weight than these parameters in cows fed soybean. Cows fed heat-treated soybeans had greater protein percentage in the milk and milk protein yield than cows fed soybean meal; however, there was tendency for higher fat tests early in lactation when cows were fed soybean. Also the results indicated that niacin supplementation improved milk production and dry matter intake, but did not influence milk composition.
439

Effect of Rations on Some Selected Blood Constituents of Dairy Heifers

Akanbi, Kamil 01 May 1985 (has links)
The study was conducted using nine Holstein heifers with weights ranging from 700 to 990 pounds (lb). The design was a 3 X 3 Latin Square. The three rations consisted of 26.5 lb of corn silage supplemented with 3 ounces of sodium bicarbonate, 26.5 lb of corn silage, and 26.5 lb of soybean and milo haylage per head per day. The rations were offered on a rotational basis for three experimental periods consisting of three weeks each. Blood samples were taken at weekly intervals during each period; plasma concentrations of glucose, ammonia, beta-hydroxybutyrate and volatile fatty acids were determined. There was no significant dietary effect on the mean group concentrations of the measured blood parameters. Also, there was no dietary effect on the performance of the animals. The correlations relative to diets showed some variations. The correlations varied in value and relationship. Mean values observed for some of the blood parameters measured indicated that the animals received adequate nutrients.
440

Seasonal Abundance & Diversity of Fishes at Three Stations on the Middle Fork of Drake's Creek, Warren & Allen Counties, Kentucky

Bell, David 01 August 1977 (has links)
A total of 7,485 fish, representing 49 species, 25 genera, and 11 families, were electroshocked from three stations on the Middle Fork of Drake's Creek during the period January, 1972 through January, 1973. Community structure was influenced by seasonal changes in both numbers of species and numbers of individuals. The number of species per collection was at its highest, at all stations, during the month of September. The total number of species and individuals collected at each station progressively increased toward the upstream areas. Eleven of the forty-nine species collected during the course of the study provided 91.8% of the total number collected. Diversity (D) values were used to compare average diversities for each of the monthly samples at each station. Monthly diversity values tended to fluctuate erratically, with the greatest stability being observed at the "mid-stream" study area. Individual species' contribution to diversity were computed using "information units" expressed as a percentage of the total diversity to find dominant species at each station and during each season. Species were categorized, according to frequency of occurrence, into permanent residents, seasonal residents, and transients. Monthly contributions to diversity, expressed in per cent, were used to compare dominant species of each category at each station. Transient species were observed to be most prominent in the lower stream reaches during the period June through September. Attempts were made to detect movement of stream fishes by mark-and-recapture techniques. The recapture of marked fish represented a return of 10.9%, as 16 of 146 marked fish were recaptured. The home range concept of some stream fishes was supported in some instances; however, streams were found to be open systems which do not lend themselves readily to mark-and recapture studies.

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