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Effects of fescue toxicosis and chronic heat stress on murine hepatic gene expression
(University of Missouri--Columbia, 2006)
Fescue toxicosis affects domestic animals grazing fescue pasture infected with the endophytic fungus, Neotyphodium coenophialum. Signs of fescue toxicosis include increased body temperature and respiration rate and decreased ...
The relationship between mitochondria and residual feed intake in feedlot cattle
(University of Missouri--Columbia, 2006)
Residual feed intake (RFI) is a measure of feed efficiency that is not related to an animal's growth rate or body size. Little is known about the factors that affect RFI because, until recently, the measurement of RFI in ...
The effects of elevated temperature on preimplantation-stage porcine embryos
(University of Missouri--Columbia, 2006)
It was the objective of these experiments to more fully characterize the biochemical and developmental responses of in vitro-produced preimplantation stage porcine embryos to elevated temperatures. In vitro fertilized (IVF) ...
Quantitative trait loci mapping and candidate gene analysis for growth and carcass traits on two bovine chromosomes
(University of Missouri--Columbia, 2006)
The first objective of this study was to identify genomic regions on BTA4 and BTA14 which harbor QTL affecting weight and carcass traits in a commercial Angus population. The mapping population consisted of 1,510 purebred ...
Morphologic and histologic comparisons between in vivo and nuclear transfer derived porcine embryos
(University of Missouri--Columbia, 2006)
Nuclear transfer (NT) is an inefficient but invaluable tool. This study examines abnormalities associated with NT porcine embryos at days 10, 12, and 14. Methods: 4 experimental groups were examined: non-pregnant, in vivo ...
The effects of supplemental anionic salts & yeast culture on the production of dairy cattle during the periparturient period
(University of Missouri--Columbia, 2006)
The objective of this thesis was to determine nutritional strategies with the strategic use of feed additives during the periparturient period to reduce the negative energy balance as the dairy cow transitions from late ...
Increasing land and forage utilization by Missouri cow/calf operations using silvopasture practices
(University of Missouri--Columbia, 2006)
Although rotational grazing has improved pasture management significantly in recent years, the need continues to exist for beef producers to increase land utilization and maintain a high level of forage production during ...
Evaluation of the efficacy of high levels of microbial phytase in broilers
(University of Missouri--Columbia, 2006)
Three experiments were conducted to evaluate the efficacy of high levels of microbial phytase in broiler diets. In experiment one (EXP 1), phytase was included in the diets at 0, 250, 500, 10,000, and 20,000 PU/kg diet. ...
Estrus induction and maintenance of cycles in gilts with PG-600 and boar exposure
(University of Missouri--Columbia, 2007)
This study looked at the efficacy of PG-600 and boar exposure to induce and maintain cycles. Gilts received one of four treatments: PG-600, weekday 10 min full physical contact boar exposure (BE), PG-600+BE, and neither ...
The effects of supplemental rumen-protected fat in feedlot rations
(University of Missouri--Columbia, 2007)
[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] Four experiments were conducted to determine the effects of supplemental rumen-protected fat in feedlot rations. The first experiment tested the effects ...
Characterization of apoptosis in the developing bovine fetal ovary: association with germ cell loss
(University of Missouri--Columbia, 2008)
[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] During early bovine fetal development a 170 fold increase in germ cells occurs from d 50 to 110 followed by a rapid decline of germ cells by d 170. To ...
11 [beta]-hydroxysteroid dehydrogenase activity in feline, equine, and ossabaw swine adipose tissue
(University of Missouri--Columbia, 2007)
Enzymatic 11 [beta] HSD1 amplification of glucocorticoid concentrations in adipose tissue has been associated with obesity, diabetes, hypertension, dyslipidemia, and cardiovascular disease in humans and mice. Unfortunately, ...
Studies of ruminant digestion, ecology, and evolution
(University of Missouri--Columbia, 2008)
This thesis examines ruminant digestion, ecology, and evolution, particularly where they can improve livestock production systems. We performed an experiment that estimated ruminal in situ degradation parameter values of ...
Comparison of thermoregulatory mechanisms in heat sensitive and tolerant breeds of Bos taurus cattle
(University of Missouri--Columbia, 2008)
Two Bos taurus breeds with known differences in heat tolerance were tested under controlled conditions to evaluate heat tolerance. Romosinuano (RO) is a tropically adapted breed. Nine Angus (304 [plus or minus] 7 Kg BW; ...
Comparison of controlled internal drug release (CIDR)-based protocols to synchronize estrus and facilitate artificial insemination (AI) in postpartum beef cows
(University of Missouri--Columbia, 2008)
Artificial insemination (AI) and estrous synchronization are reproductive technologies that enable beef producers to efficiently improve herd genetics. The recent development of protocols designed to synchronize estrus and ...
Effects of aflatoxin on hepatic gene expression in a poultry model
(University of Missouri--Columbia, 2008)
To determine the effects of dietary aflatoxin on hepatic gene expression in chicks, seventy five day old-male broiler chicks were assigned to three dietary treatments (0, 1 and 2 mg/kg aflatoxin/kg of feed) from hatch to ...
Genotype by environment interaction estimated by using reaction norms in cattle
(University of Missouri--Columbia, 2008)
The objective of this study was to evaluate GxE by comparing reaction norms among U.S. Angus bulls. Dependent variables were adjusted weights at birth, 205 d weaning, and 365 d yearling. Environments were defined as progeny ...
Endocrine associations with beef carcass quality and yield
(University of Missouri--Columbia, 2007)
[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] Serum concentrations of insulin, insulin-like growth factor I (IGF-I) and leptin were investigated relative to their association to beef carcass quality ...
Effect of RU486, a progesterone antagonist, on uterine progesterone receptor, embryonic development and ovarian function during early pregnancy in pigs
(University of Missouri--Columbia, 2009)
Progesterone (P4) down-regulates the progesterone receptor (PGR) exclusively within the epithelium of the pig uterus near d 8 of the estrous cycle and pregnancy. How P4 down-regulates the PGR is not understood but is ...
Arachidonate 15-lipoxygenase and ubiquitin as potential fertility markers in boars
(University of Missouri--Columbia, 2004)
[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] This study was performed to determine whether using high power microscopic analysis and two putative biochemical fertility markers, 15-lipoxygenase ...