Typescript. / Digitized by Kansas Correctional Industries

Thesis (M.S.)--Youngstown State University, 2008. / Includes bibliographical references (leaves 37-39). Also available via the World Wide Web in PDF format.

Master of Science / Food Science Institute / Kadri Koppel / Black walnut (Juglans nigra L.) is a Juglans species native to the United States. Nuts are collected each fall from black walnut trees and the kernels are consumed in many food products like ice cream, candies, and baked goods. Flavor profiles of black walnut cultivars have been examined, but no studies have looked at the effect of growing season on flavor profile, and few studies have determined consumer acceptance of black walnut food products. The sensory profiles of 10 black walnut cultivars (Football, Vandersloot, Brown Nugget, Pounds, Sparks 127, Davidson, Sparrow, Neel, Emma K, and Tomboy) were evaluated using descriptive sensory analysis. A trained panel scored the intensity of 3 appearance, 7 aroma, 23 flavor, and 6 texture attributes. Results showed that the cultivars differed significantly (P≤0.05) on 11 of these attributes. The results from this study were also compared to results collected in 2011 of 7 black walnut cultivars. Two flavor attributes (black walnut ID and overall nutty) had an interaction effect of year and cultivar, while 7 attributes showed a main effect of year (brown, caramelized, floral/fruity, fruity,-dark piney, musty/dusty, and oily). In general, flavor attributes had higher intensities in 2011 than in 2013. Six of the black walnut cultivars were also incorporated into a gelato base and evaluated by both a trained panel and consumer panel. Trained panelists developed a lexicon for the gelato samples and scored the intensity of 18 flavor attributes. The gelato samples differed on 3 main flavor attributes: black walnut ID, overall nutty, and sour (P≤0.05). Based on consumer liking, there were 3 distinct clusters of consumers. One cluster preferred samples with a milder black walnut flavor, another preferred a more intense black walnut and overall nutty flavor, and the third cluster liked all of the samples. Results from this study indicate that growing season should be considered when determining flavor profile of agricultural products. These results can also help guide growers in selecting cultivars that may produce a more consistent crop year after year, and cultivars that consumers find acceptable in food products.

Air drying of naturally infested soils (0.12 to 0.38% water or about -2,000 bars) resulted in no recovery of Cylindrocladium crotalariae microsclerotia, but rewetting soils to near field capacity for 1 to 4 wk before assay resulted in partial recovery from the air drying-induced decreased germinability. Numbers of germinable C. crotalariae microsclerotia (assayed at 26 C) decreased progressively over 4 wk when naturally infested soils were incubated at 6 C. No germinable microsclerotia were recovered when soils were incubated at -10 C. When soils incubated at -10 C and at 6 C were transferred to 26 C for 4 wk, the low-temperature effect was partially reversed. Incubation of naturally infested soils under field conditions over the winter months (November-February) indicated that a similar low-temperature phenomenon exists in nature. Germinability of axenic, laboratory-grown microsclerotia of C. crotalariae, C. floridanum, and C. scoparium incubated 4 wk at 6 C ranged from 0 to 91.3% (mean = 37.7%) of the initial germinability. Partial recovery of laboratory-grown microsclerotia from the lowtemperature effect, by incubation at 26 C, was demonstrated. Conductivity measurements of solutions bathing microsclerotia incubated at 6 C and 26 C for 4 wk indicated that chilling injury may account, in part, for decreased germinability of microsclerotia. Direct observation of washed conidia of C. scoparium on rewetted, non-sterile soils at 26 C indicated that peak germination (33-58%) occurred after 24 h incubation. Peak germination on continually moist soils was somewhat lower (18-26%) than on rewetted soils. Conidia did not germinate on continually moist soils at 6 C. Conidia germinated at a high level (93-95%) in axenic culture in the absence of exogenous carbon and nitrogen substrates. The inhibition of conidium germination on soils was due, in part, to the presence of fungistatic soil volatiles. Addition of low levels of carbon and nitrogen substrates nullified the inhibitory effect of soil volatiles. Germinability of C. scoparium, C. crotalariae, and C. floridanum conidia in artificially infested soils (assayed on a selective medium at 26 C) decreased progressively during incubation at 26 C from 1 wk to 4 mo. No germinable conidia were recovered after incubation of soils at 6 C for 4 wk. Control of Cylindrocladium root rot of black wainut seedlings with sodium azide at 224 kg/ha applied by the plowdown method was comparable to MC-33 at 504 kg/ha. Sodium azide at 67 kg/ha was only marginally effective in disease control. Reduction of Cylindrocladium microsclerotium populations, qualitatively assayed by the azalea leaftrap method, was found in soil samples from plots fumigated with sodium azide and MC-33. A small-spored Cylindrocladium sp. with clavate to papillate vesicles, identified as C. parvum, was consistently recovered from diseased roots and soil samples from a Virginia forest nursery. Percentage recovery from necrotic roots and soil samples collected from root zones of necrotic black walnut seedlings was appreciably higher for C. parvum than for C. floridanum or C. scoparium. In greenhouse tests, limited pathogenicity of C. parvum on black walnut seedlings was demonstrated. / Ph. D.

Integrating trees into pasture may be an effective management tool to improve water, nutrient, and light allocation and increase total system productivity in Appalachia. We tested this hypothesis in a silvopasture near Blacksburg, VA. In 1995, black walnut and honey locust trees were planted within plots (r=3) of predominantly tall fescue pasture. Across a 12% slope, trees were planted to create treatments of low, medium, and high tree densities at shoulder, mid, and toe slope positions within plots of honey locust and black walnut. Sampling sites (n=54) under tree density and slope position combinations were harvested May to October at 35-d intervals in 2002 and 2003 for determination of yield and nutritive value characteristics. Soil surface temperature, forage canopy temperature, soil moisture, and photosynthetically active radiation were measured to determine forage responses to field treatments as functions of resource allocation. Tree density had the greatest effect on forage production and nutritive value. Across both years, yields were 16% greater (P=0.0006) at medium density (6130 kg/ha) compared to forage mass at low (5280 kg/ha)) and high density (4970 kg/ha, SE=130). Increasing tree density did not affect (P>0.2) ADF, CP, P, K, and Mg levels, but reduced (P<0.001) NDF and TNC, and increased (P<0.0001) ADL and Ca. Elevated soil surface and forage canopy temperatures limited forage production and nutritive value at low density, while low light levels were the limiting factor at high density. Moderating forage microclimate with appropriately spaced trees is an effective way to improve forage production in temperate pastures. / Master of Science

Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 185-200). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves 185-200). Also available on the Internet.

Black walnut (Juglans nigra L.) is a valued, Mississippi tree species with very little published mensurational data. Tree profile equations are effective tree volume predictors but are typically developed from measurements on destructively sampled trees, an impractical method on valuable species. This study developed black walnut and green ash (Fraxinus pennsylvanica) profile equations from non-destructive measurements using a Barr & Stroud FP15 optical dendrometer. Accuracy of the dendrometer was validated by taking both optical dendrometer and felled, direct measurements on green ash trees. Two profile models were evaluated for measured tree data. Separate equations were created from optical dendrometer tree profile data for black walnut and green ash and felled tree profile data for green ash. The Barr & Stroud allowed tree profile equations to be developed from standing tree measurements with acceptable accuracy, thus providing useful tools towards the valuation and management of southeastern black walnut and green ash.

Animal welfare is a major concern among livestock producers in the U.S. Heat stress, particularly, compromises animal welfare and productivity, causing >$2B annual economic loss to producers. The presence of toxic alkaloids within tall fescue (Schedonorus phoenix syn Lolium arundinaceum, syn Festuca arundinacea) plants induces a complex of disorders collectively known as fescue toxicosis. Summer slump, a reduction in animal performance due to heat stress, is common and evident of the symptoms. Various techniques for assessing animal physiological and behavioral responses to heat stress were explored in this dissertation, with particular emphasis on fescue toxicosis and its mitigation strategies. In the first study, the physiological and behavioral responses of heifers was evaluated when grazing either toxic tall fescue with wildtype endophyte (WE) or tall fescue with a novel endophyte (NE). Heifers (n = 24) were assigned to either WE or NE pastures for a 56-d grazing study during the summers of 2020 and 2021. Heifer average daily gain (ADG), intravaginal temperature, and degree of hair shedding were recorded during the grazing period. Blood samples were collected through coccygeal venipuncture and hair was collected from the left rump for cortisol analysis. Ear, tail, and hoof temperatures were collected for each heifer using an infrared thermal imaging camera. In 2020, heifers that grazed NE tall fescue had greater (P = 0.0160) ADG over the season (0.22 vs. 0.12 kg day-1). Hair retention score was greater (P = 0.0029) for heifers that grazed WE tall fescue compared to heifers that grazed NE tall fescue across both years. Heifers that grazed WE tall fescue had decreased ear skin temperature (P = 0.0001), tail skin temperature (P = 0.0058), and hoof surface temperature (P = 0.0075) compared to heifers that grazed NE. Heifers that grazed WE had 0.3-0.9 ºC hotter intravaginal temperatures than heifers that grazed NE, especially during daytime. Hair cortisol levels of heifers that grazed WE tall fescue were greater (P < 0.0001) compared to hair cortisol levels of heifers that grazed NE tall fescue. From 1200h-1700h each day, heifers that grazed WE tall fescue spent 1.5 more (P = 0.0003) hours standing and 0.9 fewer (P = 0.0402) hours lying down compared to heifers that grazed NE tall fescue. These results suggest that heat stress and other physiological changes in heifers grazing WE tall fescue could be mitigated by renovating pastures with NE tall fescue that does not impose any negative effects on grazing animals. The second study explored the potential benefits of consuming condensed tannins as a means of negating the effects of toxic alkaloids in tall fescue. Twelve fall-born steers were assigned to one of the two diet supplement treatments - sericea lespedeza pellets (LES) or sericea lespedeza pellets mixed with polyethylene glycol (LES+PEG) for 12 weeks during the summers of 2020 and 2021. The LES+PEG treatment served as a positive control since polyethylene glycol binds tannins, rendering them inactive in the gastrointestinal system. Animal body weight (BW), hair retention score (HRS), rectal temperature, and thermographic images were collected every 4 weeks. Hair and blood samples were also collected for cortisol analysis. Fecal and urine samples were collected and analyzed for total ergot alkaloid (TEA) concentration. Steers on LES had greater (P = 0.0033) ADG compared to steers on LES+PEG in 2021, but not in 2020 (P = 0.8707). In 2021, HRS was greater (P < 0.05) for steers fed LES+PEG compared to steers fed LES. In 2020, ear skin temperature (P < 0.0001) and hoof surface temperature (P = 0.0382) was greater in steers on LES compared to steers on LES+PEG. Rectal temperatures were lower (P = 0.02905) for steers fed LES compared to steers fed LES+PEG in 2021. Plasma cortisol levels did not differ (P ≥ 0.1566) between LES and LES+PEG treatments for both years. In 2020, hair cortisol levels did not differ (P = 0.8295) between treatments while in 2021, the hair cortisol level of steers on LES+PEG was greater (P = 0.0221) compared to hair cortisol levels of steers on LES. This study indicated some changes in animal physiology in response to dietary supplements containing condensed tannins, but results were inconsistent and further studies are needed to better understand the potential benefits of tannins in reducing the effects of toxic alkaloids consumption. In the third study, behavioral and physiological responses of ewes that grazed either mid-stage hardwood silvopastures or open pasture (OP) were compared. The study site consists of 0.27-ha of black walnut (Juglans nigra; BSP) and honeylocust (Gleditsia triacanthos; HSP) silvopastures and open pasture treatments, each replicated three times. During the summers of 2020 and 2021, thirty-six Katahdin ewes were assigned to one of the treatments for a 6-week summer grazing trial. Ewe weights were recorded for two consecutive days at the beginning and end of the study and intravaginal temperatures were recorded for two consecutive days at every 3-week intervals. Trail cameras captured animal behavior. Blood was collected via jugular venipuncture. Hair grown during the trial was collected from the loin region. Blood and hair cortisol concentrations were determined by ELISA. Ewe ADG was greater in HSP compared to OP (P = 0.0456) but did not differ with BSP (P = 0.4686) across both years. Ewes on OP had hotter (P ≤ 0.0343) intravaginal temperatures than ewes on both silvopasture treatments between 1100h-1700h. Plasma cortisol level was lower in ewes on BSP compared to ewes on OP (P = 0.0400) but did not differ with ewes on HSP (P = 0.6954) across both years. Ewes that grazed OP had greater hair cortisol levels compared to ewes on silvopasture treatments both in 2020 and 2021 (P < 0.0001). In 2020, ewes on BSP spent about 20% more time grazing than ewes on OP (P = 0.0054) while in 2021 ewes on BSP spent about 36% more time grazing than ewes on HSP (P = 0.0014). Ewes on OP spent 400% more time standing than ewes on BSP (P < 0.0001) and 750% more time standing than ewes on HSP (P < 0.0001). Ewe on OP spent 20% less time lying down compared to ewes on BSP (P < 0.0001) and 33% less time lying down compared to ewes on HSP (P < 0.0001). Hair cortisol measures and intravaginal temperature sensors can be utilized as reliable and relatively non-invasive techniques for measuring heat stress response in livestock managed in extensive grazing systems. / Doctor of Philosophy / Heat stress compromises animal welfare and productivity, causing > $2B annual economic loss to producers in the U.S. In the southeastern U.S, heat stress in livestock is largely due both to an environmental condition and to the effect of fescue toxicosis caused by toxic alkaloids. Various management strategies to mitigate the effect of heat stress in livestock due to environmental conditions or due to the effect of tall fescue toxicosis are explored in this dissertation. In the first study, behavioral and physiological responses of heifers that grazed either toxic (WE) or novel (NE) endophyte-infected tall fescue was compared. Heifers that grazed WE tall fescue had lower gains, rough hair coat, higher hair cortisol level (stress measure), cooler extremity temperature, and hotter intravaginal temperature compared to heifers that grazed NE tall fescue. These results suggest that heat stress and other physiological changes in heifers grazing WE tall fescue could be mitigated by renovating pastures with NE tall fescue, a forage cultivar that does not impose any negative physiological effects on grazing animals. In the second study, we tested the effect of condensed tannins in reducing the severity of fescue toxicosis in steers. We fed sericea lespedeza pellets to steers in a study to test this effect. All steers were fed sericea pellets, but pellets for half (6) of the steers were treated with polyethylene glycol, which inactivates the condensed tannins in the sericea lespedeza. In our study, we found that the steers fed the sericea lespedeza had higher temperatures at their extremities (ears and tail), but lower rectal temperatures than the control steers. Interestingly, the steers fed the sericea lespedeza pellets also had slicker hair coats and lower levels of hair cortisol (indicating reduced stress) in the second year compared to the control steers. This study showed some potential of condensed tannins in reducing the effects of fescue toxicosis, but needs further study to better understand the potential benefits of tannins in reducing the post-ingestive effects of fescue toxicosis. In the third study, we compared behavioral and physiological (temperature, hair, and blood cortisol) responses of ewes that grazed either mid-stage hardwood silvopastures or open pastures (OP). Ewes on OP showed signs of heat stress with higher hair cortisol levels and hotter intravaginal temperatures during the daytime compared to ewes on silvopasture treatments. Ewes on OP spent 400% more time standing compared to ewes on BSP and 750% more time standing than ewes on HSP. Ewe on OP spent 20% less time lying down compared to ewes on BSP and 33% less time lying down compared to ewes on HSP. Ewes on silvopasture treatments spent 70% less time drinking water compared to ewes on OP. Trees within the silvopasture systems can alter the micro climatic condition thus creating a suitable environment for livestock. This can ultimately reduce stress and improve overall behavioral and physiological responses of livestock in silvopastures compared to open pastures.

Reclamation of surface mined lands is required under the Surface Mining Control and Reclamation Act of 1977. Reforestation of mined lands is challenging due to harsh conditions such as soil compaction, herbaceous competition, and animal browse. We investigated the field performance of black walnut (<i>Juglans nigra</i>), northern red oak (<i>Quercus rubra</i>), and swamp white oak (<i>Quercus bicolor</i>) planted on two mine reclamation sites and evaluated the interactions of nursery stocktypes (container and bareroot), herbicide application, and tree shelters. Survival averaged 80% across all species and stocktypes after two years. Container stocktype had greater relative height and diameter growth, whereas bareroot had greater total height and diameter growth likely due to initial stocktype differences. Shelter use increased height growth and reduced diameter growth across both stocktypes. Swamp white oak (<i>Q. rubra</i>) had high survival and field performance regardless of silvicultural treatment, whereas the two other species showed strong early regeneration responses to silvicultural treatments. Container seedlings showed promise as an alternative to bareroot seedlings to promote survival and early growth on mine reclamation sites. Future research should be on continued development of container stocktypes to provide an economically feasible mine reclamation option for land managers.