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Sexually naïve female prairie voles require exposure to a novel male to activate the neural circuits involved in the formation of stable pair bonds and to stimulate sexual receptivity. The objective of our study was to ...

Short-term storage trials were conducted in 2008 and 2009 on Atlantic sturgeon semen obtained from captive males, held at the U.S. Fish and Wildlife Service, Northeast Fish Technology Center, that were hormonally induced ...

The metabolism of feline follicles has been largely overlooked in reproductive science. The primary objective of this study was to determine differences in metabolite profiles and glucose carbon fluxes in feline follicles ...

In chickens, the primary energy substrate is lipid during embryogenesis and carbohydrate after hatch. Accordingly, chicks adapt their metabolism to utilize glucose after hatch; however, little is known about metabolic ...

Calorie restriction (CR) has been established as the only non-genetic method of altering longevity and attenuating biological changes associated with aging. This nutritional paradigm has been effective in nematodes, flies, ...

Metazoans synthesize and regulate intracellular heme in a cell autonomous manner although genetic evidence in vertebrates suggests that cell non-autonomous mechanisms may exist at the organismal level. In <italic>C. ...

The ionophore monensin improves feed efficiency (FE) by increasing sodium uptake in rumen bacteria, which alters rumen fermentation. Dietary cation-anion difference (DCAD) represents the balance between the dietary strong ...

The objective of this study was to discern whether providing enrichment in the form of barrier perches across a range of densities might improve leg and foot health and promote behavioral expression and more even use of ...

The objective of this thesis research was to determine the pathways of glucose metabolism and utilization in small and large egg embryos during the latter half of development, and whether in ovo nutrient supplementation alters glucose use. A further objective was to determine the contribution of glutamate, glutamine and glycerol to glucose, glycogen and non essential amino acid (NEAA) synthesis during embryo development. In ovo stable isotope ([U-¹³C]glucose, [U-¹³C] glutamate, [U-¹³C]glutamine and [U-¹³C]glycerol) injection approaches were developed along with mass isotopomer distribution analysis of metabolic intermediates and end-products to acquire a metabolic phenotype of the fluxes and partition of these substrates through central pathways. Embryos developing in small and large eggs maintained similar rates of glucose metabolism. Thus, glucose entry and utilization gradually increased from day 12 to 18 embryonic. By embryonic day 20, gluconeogenesis accounted for >80% of glucose entry, a part (65%) of which was represented by glucose carbon recycling. Glutamate and glutamine were not found to be significant gluconeogenic precursors in day 19 embryos. However, catabolism of these amino acids contributed to ~25% of proline flux in the liver. By contrast, there was significant [M+3] ¹³Cisotopomer abundance in blood glucose and in liver and muscle glycogen when [U- ¹³C]glycerol was injected in ovo. These observations clearly confirmed that glycerol derived from triacylglycerides is a significant precursor for glucose and glycogen synthesis. In ovo supplementation on day 9 embryonic of glucose and/or amino acids (5 non-essential amino acids) did not alter gluconoegenesis. However, these supplemental treatments significantly reduced catabolism of glucose via glycolysis. ¹³C-Mass isotopomer abundances of most substrates differed when each was individually compared in blood and in the various tissues, indicating differences in substrate utilization between tissues. In summary, this thesis research has provided new information on the degree and pathways of nutrient (glucose, glycerol, amino acids) use by the developing embryo and the rapid adjustments in the activity of networks of enzymes involved in non-essential amino acid, glucose and glycogen metabolism to support embryo survival. Most importantly, this work has systematically evaluated the potential substrates that the embryo utilizes for glucose synthesis, in particular, the significant role of glycerol....

The objective was to determine the optimal dietary cation-anion difference (DCAD) required to maximize 3.5% fat-corrected milk (FCM) and feed efficiency (FE; FCM per dry matter intake (DMI)) in lactating dairy cows. When ...