<p>Ovarian stimulation in assisted reproduction often leads to the production of a high number of oocytes. After fertilization of these oocytes, the resulting embryos can be cryopreserved for later use. Vitrification is a recently introduced method for cryostoring embryos, showing high survival rates for both cleavage stage embryos and blastocysts. Characteristic of vitrification are high concentrations of cryoprotectants and ultra fast freezing which makes the material glassily. A major concern with vitrification has been the direct contact of the cryo-solutions with liquid nitrogen. Therefore, sealed containers have been developed and one of these is the Rapid-i™ made by Vitrolife Sweden AB.</p><p>We evaluated this new device using embryos not suitable for embryo transfer or cryopreservation for clinical purposes. Embryos at cleavage stages were first vitrified and then warmed. Outcome parameters were cryosurvival and development to the blastocyst stage. Blastocysts were randomised between the established VitroLOOP™ and the Rapid-i™ as carriers. Outcome parameters were cryosurvival and further development. Our results show that Rapid-i™ gives good survival rates in vitrification for cleavage stage embryos and blastocysts.</p>

The total amount of nitrogen and phosphorus in animal manures, and the proportion of this amount that becomes available as dissolved inorganic nitrogen and phosphorus within a month after manures are added to water were examined in the context of fertilization guidelines for pond aquaculture. A literature study was conducted to synthesize information on the dry matter, total nitrogen and total phosphorus contents, and the biochemical oxygen demands of different manures. This information was used to compile a fertilizer database and to examine dry matter-nutrient relationships for different manures. Significantly high correlations between dry matter and total nitrogen, and between dry matter and total phosphorus were observed for poultry manure, and different forms of beef and dairy cattle manures. These relationships can be used to estimate the nutrient contents of manures if the dry matter contents are measured. A laboratory experiment was conducted to determine the amount of nitrogen and phosphorus that becomes available as dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorus (DIP) over a five week period when poultry, swine and dairy manures are added to water. Mean DIN and DIP concentrations reached highest levels on the 5th day after manure addition for all the manures. These concentrations corresponded to 60.5, 49.5 and 30.1% of the total nitrogen and 78.4, 77.4 and 58% of the total phosphorus supplied by poultry, swine and dairy manures respectively. DIN and DIP concentrations were significantly different among the three manures on all sampling days. Poultry manure supplied the highest amount of nitrogen and phosphorus, followed by swine and dairy manures. Pond fertilization guidelines based on the nitrogen and phosphorus requirements for algae should consider the available portion and not the total nitrogen and phosphorus contents of manures to calculate fertilizer requirements. Another study was conducted to examine the effects of temperature and repeated manure addition on nutrient release patterns from poultry manure. Different temperatures over a three week period did not have a pronounced impact on DIN and DIP levels. Two phases of DIN build-up were observed, whereas DIP levels showed an increasing pattern throughout the temperature experiment. The overall proportion of the total nitrogen and phosphorus supplied by poultry manure that became available as DIN and DIP for all the experimental units considered together amounted to about 64 and 70% respectively, which is consistent with the earlier study. Repeated manure addition resulted in significantly lower DIN and higher DIP concentrations in the interval following the second manure addition compared to the first interval, although nutrient release patterns appeared to be similar. / Graduation date: 1993

Ovarian stimulation in assisted reproduction often leads to the production of a high number of oocytes. After fertilization of these oocytes, the resulting embryos can be cryopreserved for later use. Vitrification is a recently introduced method for cryostoring embryos, showing high survival rates for both cleavage stage embryos and blastocysts. Characteristic of vitrification are high concentrations of cryoprotectants and ultra fast freezing which makes the material glassily. A major concern with vitrification has been the direct contact of the cryo-solutions with liquid nitrogen. Therefore, sealed containers have been developed and one of these is the Rapid-i™ made by Vitrolife Sweden AB. We evaluated this new device using embryos not suitable for embryo transfer or cryopreservation for clinical purposes. Embryos at cleavage stages were first vitrified and then warmed. Outcome parameters were cryosurvival and development to the blastocyst stage. Blastocysts were randomised between the established VitroLOOP™ and the Rapid-i™ as carriers. Outcome parameters were cryosurvival and further development. Our results show that Rapid-i™ gives good survival rates in vitrification for cleavage stage embryos and blastocysts.

Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves 246-266). Also available on the Internet.

Thesis (M.S.)--Rutgers University, 2009. / "Graduate Program in Cell and Developmental Biology." Includes bibliographical references (p. 58-65).

Thesis (Ph. D.)--University of Michigan, 1926. / Caption title. Thesis note in foot-note on p. 301. "Contributions from the Department of Zoölogy, Smith College, no. 138." "Reprinted from Biological bulletin, vol. L., no. 4, April, 1926." "Literature": p. 335-338.

published_or_final_version / Social Work and Social Administration / Doctoral / Doctor of Philosophy

Not available / text

Originally Published: 1997; Revised / 5 pp. / Foreign sudangrass hay buyers want dust-free hay with a bleached light green color and a stem diameter less than one quarter of an inch. Two types of sudangrass hybrids are currently grown in the United States: true sudangrass hybrids and sorghum-sudan hybrids. Sudangrass and related hybrids are annual warm season grasses grown for pasture, green chop, silage, and hay. Sudangrass produces well on all soil types, however best yields are obtained on well-drained, deep loam soils that have a high capacity to absorb and hold water. Sufficient nitrogen should be applied at planting to ensure establishment of the crop and hasten development. Typically, 40 to 80 pounds of actual nitrogen per acre are suggested at planting, based on results from a preplant nitrate-nitrogen soil test. This should be followed by split applications of 60 to 120 pounds actual nitrogen per acre in irrigation water following each cutting. Harvest sudangrass when it is at least 18 to 24 inches tall at the first cutting. Nitrates present in hay crops are considered toxic to many classes of livestock. Most cases of hydrocyanic or prussic acid poisoning are caused by the ingestion of plants that contain cyanogenetic glucosides. Cyanogenetic glucoside itself is non-toxic but hydrocyanic acid.

Annual application of N at rates of 118 (118N), 236 (236N), and 354 (354N) kg•ha⁻¹ on 35 year old 'Western Schley' pecan trees during four years had little effect on mineral composition and foliar N. No differences in yield, nut quality, and reproductive characteristics were found. Alternate bearing intensity in four consecutive years was 37, 33 and 28% in 118N, 236N, and 354N, respectively, with a significant linear response. Rates from 118 to 236 kg N•ha⁻¹ satisfy N needs for pecan in irrigated pecan orchard of the southwest of United States. The effect of one-time banding of zinc sulfate (74 kg Zn•ha⁻¹) and zinc-EDTA (19 kg Zn•ha⁻¹) was evaluated over a period of four years on ‘Wichita’ pecans growing in alkaline soil. Significant differences in foliar Zn levels were found one month after application of Zinc-EDTA. Differences also were noted during the next three years on approximately 25% of the sampling dates. Yield, leaflet area, and trunk cross sectional area were not affected. Zinc-EDTA increased Zn uptake by 'Wichita' pecan trees in alkaline conditions during three years. A field study indicated that manure or manure plus Zn increased foliar Zn levels in pecans after two years of annual applications. Manure (24 ton ha⁻¹) plus zinc sulfate (258 kg Zn•ha⁻¹ as zinc sulfate) treatment had the highest foliar Zn levels. No differences were observed in trunk growth, leaf area, leaf weight, nut filling, and yield. Manganese toxicity symptoms are exhibited when leaf Mn levels are higher than 1700 μg•g⁻¹ during the standard date sampling of July and affected reproductive characteristics and leaf and shoot growth. More severe visible symptoms include delayed budbreak and die-back of young shoots. In potted pecan trees, zinc EDTA treated trees had a foliar Zn of 244 μg•g⁻¹, in foliar sprayed trees (eight foliar sprays of a combination of zinc sulfate and UAN32) had 140 μg•g⁻¹, and in control trees had 33 μg•g⁻¹. Soil adsorption isotherms showed that of the three fertilizers evaluated Zn sulfate was adsorbed most strongly by the soil (1.5 mg Zn•g⁻¹ of soil). Soil adsorption from Zn EDTA solutions was insignificant.