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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.
131

The effects of low-, medium-, and high-oil dried distillers grains with solubles (DDGS) on growth performance, nutrient digestibility, and fat quality in finishing pigs

Graham, Amanda Brooke January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Robert Goodband / Three experiments used 1,756 pigs to evaluate the effects of corn dried distillers grains with solubles (DDGS) varying in oil content on growth performance, carcass characteristics, and fat quality in growing-finishing pigs. A fourth experiment used 12 pigs and determined the energy concentration and nutrient digestibility of the DDGS sources used in the previous 3 growth studies. Lastly, a fifth experiment used 576 pigs to determine the effects of DDGS and wheat middlings (midds) withdrawal 24 d before harvest in diets without or with ractopamine HCl (RAC) on growth performance, carcass characteristics, fat quality, and organ/intestine weights. Experiment 1 determined that increasing 7.4% oil DDGS decreased (linear, P < 0.02) ADG and G:F. Also, final BW, HCW, and carcass yield decreased (linear, P < 0.03), but jowl iodine value (IV) increased (linear, P < 0.001) as DDGS increased. Experiments 2 and 3 utilized DDGS sources that contained 5.2 vs. 9.3, and 9.2 vs. 11.8% oil, respectively. In brief, results suggested that while ADG was unaffected, feeding DDGS with 5.2% oil reduced G:F. In Exp. 4, stepwise regression was used to develop prediction equations based to determine that a 1% change in oil content of DDGS will change the DE by 71 kcal/kg and NE by 118 kcal/kg. Experiment 5 determined that pigs fed corn-soy (CS) diets throughout the finishing phase had greater (P < 0.03) ADG, G:F, and carcass yield and lower (P < 0.01) IV than those fed high fiber (HF; DDGS and wheat midds) diets throughout, with pigs fed the fiber withdrawal intermediately. Pigs fed RAC had greater (P < 0.01) ADG, G:F, and carcass yield than pigs not fed RAC. Iodine values were lowest (P < 0.01) for pigs fed the CS diets, highest (P < 0.01) for those fed HF diets throughout, and intermediate for pigs fed the withdrawal diet. Withdrawal of the HF diet to a CS diet partially mitigated negative effects on carcass yield and IV, and feeding RAC, regardless of dietary fiber regimen, improved growth performance and carcass yield.
132

The effects of dietary soybean hulls, wheat, crystalline amino acids and high protein corn dried distiller’s grains on nursery and/or finishing pig growth and carcass characteristics

Goehring, Devin Lynn January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Jim Nelssen / Six experiments using 3,659 nursery and finishing pigs were conducted to evaluate the effects of dietary soybean hulls and ingredient processing in corn-soybean meal or corn-soybean meal-DDGS diets on nursery and finishing performance. Experiment 1 tested increasing soybean hulls (0, 5, 10, 15, and 20%) and increasing soybean hulls decreased ADG and G:F. Experiment 2 evaluated increasing soybean hulls (0, 10, and 20%) in diets balanced or not for NE and showed reduced performance with increasing soybean hulls. Balancing for NE resulted in G:F similar to pigs fed the control. Experiments 3 and 4 evaluated increasing dietary soybean hulls in corn-soybean meal and corn-soybean meal-DDGS diets. Soybean hulls in either diet worsened G:F and improved caloric efficiency, suggesting current INRA (2004) values for soybean hulls underestimate their energy value. Experiment 5 evaluated 10 and 20% ground or unground soybean hulls in meal and pelleted diets. Caloric efficiency improved with high levels of soybean hulls. Pelleting improved ADG and eliminated negative effects on G:F with increasing soybean hulls, while grinding soybean hulls reduced performance. Experiment 6 tested increasing ground and unground soybean hulls (0, 7.5, and 15%). Increasing soybean hulls worsened G:F, carcass yield, and hot carcass weight. Grinding soybean hulls to finer particle sizes did not improve ADG and worsened G:F. Experiments 7 and 8 evaluated the replacement of corn with wheat and crystalline amino acids in nursery and finishing pig diets. Replacing 50% of corn with wheat did not affect growth performance in either nursery or finishing; however 100% replacement of corn with wheat reduced performance. In addition, feeding wheat improved carcass fat IV, while use of high levels of crystalline amino acids in wheat-based diets did not influence performance in either study. Experiment 9 evaluated the replacement of soybean meal with high-protein dried distiller’s grains with solubles and crystalline amino acids. High-protein DDGS and crystalline AA can replace 50% of the SBM in finishing diets without negatively affecting performance or carcass yield. Replacing 100% of SBM with high-protein DDGS reduced growth rate, but increasing crystalline AA levels can help mitigate negative effects on carcass yield and fat IV.
133

Phenotypic and genetic relationships among temperament, immune, and carcass traits in beef cattle

Bates, Kerri E. January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Jennifer Minick-Bormann / Cattle temperament has historically influenced selection decisions due to ease of handling. However, temperament may also influence economically relevant traits. The purpose of this study was to investigate relationships between temperament, Bovine Respiratory Disease (BRD) incidence, and resulting carcass merit in feedlot steers. Across a two year period, 2,870 crossbred steers were shipped from a single ranch source to a feedlot. At the time of feedlot placement, as well as at the time of reimplantation, temperament was measured via chute score (CS) and exit velocity (EV). Blood samples were taken upon arrival to the feedlot to determine circulating concentrations of interleukin 8 (IL-8) and cortisol, both of which are involved in immune function. Performance traits, including weight and gains, were measured at feedlot placement (d 0), reimplantation (d 73-100), and again 59 to 70 days later. Recorded carcass data included HCW (HCW), USDA yield grade (YG), marbling score (MS), ribeye area, and lung scores. Phenotypic statistical analysis was performed with SAS statistical software (SAS Inst., Inc., Cary, NC) and genetic parameters were estimated using ASREML (Ver. 3.0, VSN International, Ltd., Hemel Hempstead, UK). The pedigree file included records of 7,177 animals with up to 7 generation of pedigree. Contemporary group (CG, n=11) included initial ranch unit, date of arrival to the feedlot, feedlot pen, and processing dates. Fixed effects included in the model were pre-feedlot entry BRD treatment and CG. Cattle with higher CS at placement subsequently had more BRD incidence (P < 0.01). There was a positive phenotypic correlation between placement CS and blood cortisol concentrations (r = 0.07; P< 0.01), and cattle with higher cortisol concentration contracted BRD more often than their calmer peers (P < 0.05). Circulating IL-8 concentration had no influence on feedlot health. At the time of reimplantation, cattle that had been treated for BRD in the feedlot had lower chute scores (P < 0.001). Heritability estimates for CS at placement, EV at placement, CS at reimplantation, and EV at reimplantation were 0.23, 0.17, 0.19, and 0.27, respectively. BRD incidence had a negative genetic correlation with all measures of temperament recorded at the second processing period.
134

The effects of nutrition and reproductive strategies on performance of beef cattle grazing native shortgrass range in western Kansas

Bennett, Bradley Wayne January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / John Jaeger / Cattle grazing dormant native range (< 7% crude protein; CP) require supplementation of additional protein to sustain body weight (BW) and body condition score (BCS). Daily delivery of these supplements is an economic burden to cattle producers faced with challenging economic circumstances. Supplementing cows infrequently (as little as once/week) has produced equivalent BW and BCS changes compared to daily delivery. Dried distiller’s grains with solubles (DDGS) provides more ruminally-undegradable protein (RUP; 50-60%) compared to traditional oilseed-meal supplements (i.e. soybean meal) that are >50% ruminally-degradable protein (RDP). Therefore, our objective was to evaluate the effects of supplementation frequency on performance, reproductive success, eating behavior, and subsequent calf performance of spring-calving cows supplemented with DDGS. No differences in ending BW (P = 0.69) and BCS (P = 0.49), or changes in BW and BCS over the supplementation period (P = 0.82 and 0.70, respectively) were observed among cows supplemented every d, every 3 d, or every 6 d. Calf BW at birth, weaning weight (WW), and average daily gain (ADG) were similar among treatments (P = 0.19, 0.12, and 0.10, respectively). First-service conception rate (FSCR) and final pregnancy rate (PR) were also not affected by supplementation frequency (P = 0.62 and 0.76, respectively). The development of replacement heifers is a large expense for cow-calf producers. Improved breeding and heifer development strategies aimed at ensuring the success of replacement females have been developed but reproductive failure still remains a problem. The stress associated with breeding and handling procedures may decrease reproductive success. Therefore, the objective was to determine if intramuscular administration of flunixin meglumine (1.1 mg/kg BW) 14 days post-breeding would improve FSCR and PR in non-transported replacement heifers. Under the conditions of our study, flunixin meglumine did not improve (P = 0.87) first service conception rate above that of control heifers (41.2% and 42.3%, respectively). Final pregnancy rate also was not different between treatments and averaged 81.8% (P = 0.40).
135

Effect of limonene on ruminal Fusobacterium necrophorum

Saed Samii, Sina January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Evan C. Titgemeyer / Seven ruminally cannulated heifers approximately 225 kg initial BW were used in a 7 × 4 Youden square design to determine the effects of different levels of limonene on ruminal Fusobacterium necrophorum populations. Treatments included: 1) control, 2) limonene at10 mg/kg diet DM, 3) limonene at 20 mg/kg diet DM, 4) limonene at 40 mg/kg diet DM, 5) limonene at 80 mg/kg diet DM, 6) CRINA-L (a blend of essential oil components) at 180 mg/kg diet DM, 7) tylosin at 12 mg/kg diet DM. Each period included 11 d with 10 d washouts between periods. Samples were collected on d 0 (before treatment initiation), 4, 7, and 10 for measuring F. necrophorum by most probable number (MPN) method using selective culture medium. Results indicate that CRINA-L (P = 0.52) and tylosin (P = 0.19) did not affect ruminal F. necrophorum populations. Limonene linearly decreased (P = 0.03) F. necrophorum populations, and the optimal dietary concentration for limonene was 40 mg/kg DM. Limonene did not affect ruminal degradation rate of lysine, NH3 concentration, or VFA profiles in ruminal fluid. Limonene was useful for reducing ruminal concentrations of F. necrophorum. It may have potential to control liver abscesses, although further research will be needed to assess the effect of limonene under feedlot conditions.
136

Color and flavor stability of beef gluteus medius as influenced by postmortem aging time and blade tenderization

Dietz, Garret January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Terry Houser / A total of 45 top sirloin butts (IMPS 184) were procured from three commercial beef processing facilities to determine the effects of post-mortem aging time and blade tenderization on the quality of beef gluteus medius (GM) steaks. Top sirloin butts were randomly assigned to five post-mortem aging periods (5, 19, 33, 47, and 61 days). One-half of each beef GM was randomly assigned to either a blade tenderized treatment or a non-blade tenderized treatment that was not blade tenderized. Steaks were then evaluated for thiobarbituric acid reactive substances (TBARS), metmyoglobin reducing activity (MRA), oxygen consumption rate (OCR), visual color panel, instrumental color, Warner-Bratzler shear force (WBSF), Lactic Acid Bacteria (LAB) enumeration, pH, and sensory properties. Aging × blade tenderization interactions (P < 0.05) were found for display color panel, discoloration panel, WBSF, overall tenderness, myofibrillar tenderness, bloody/serumy, metallic, overall sweet, and bitter (P < 0.05). As steaks were aged longer and blade tenderized they became more discolored during display and more tender. In addition, there were aging × display time interactions (P < 0.05) observed for L*, a*, b*, display color panel, and discoloration panel. As steaks were aged longer, they had increased L*, a*, b*, and hue angle values and display color panel scores when initially put into a retail case, but L*, a* and b* decreased and discoloration scores increased as display time increased. Furthermore, there were blade tenderization × display time interactions (P < 0.05) found for display and discoloration panels. Blade tenderized steaks discolored faster in retail display than non-blade tenderized steaks. With increased aging time, there was an increase (P < 0.05) in TBARS, OCR, initial color panel, LAB enumeration, and warmed-over flavor, as well as a decrease in MRA. Also, as aging increased there was a decrease (P < 0.05) in MRA, initial color panel scores, and WBSF values. Blade tenderization significantly increased (P < 0.05) initial color panel scores, rancid flavor, and spoiled flavor. Increasing the aging time of the GM, produced steaks with decreased color stability, altered the flavor profile, and increased tenderness. Blade tenderization significantly increased tenderness, increased discoloration in a retail case, and produced more undesirable flavors.
137

Evaluation of the 5-day vs. 7-day Co-Synch + CIDR protocol in dairy heifers using timed AI.

Mellieon, Harold Irvin Jr. January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Jeffrey S. Stevenson / Our objectives were to determine: the effectiveness of upfront PGF2α injection to regress the corpus luteum; ovulation response to GnRH; and pregnancy outcomes. Dairy heifers (n = 545) from three locations (Florida, Kansas, and Mississippi) were assigned randomly to each of two treatments: 1) 25 mg of PGF2α injection and insertion of previously used autoclaved CIDR on d 7 followed by 100 µg of GnRH administered on d 5, and a 25 mg PGF2α injection at CIDR removal (7D) on d 0; 2) 100 µg of GnRH and insertion of previously used autoclaved CIDR on d 5 and 25 mg of PGF2α injection at CIDR removal (5D) on d 0. Artificial insemination (AI) occurred after detected estrus from d 0 to 3. Those heifers not detected in estrus were inseminated on d 3 and given a second 100 µg of GnRH. Blood collected on d 7 and 5 was assayed to determine concentrations of progesterone, presence of a CL (progesterone ≥1 ng/mL) on d 7, and whether luteolysis occurred in 7D heifers. Blood progesterone concentration from d 0 and 3 determined if luteolysis occurred in all heifers. Ovarian structure maps on d 5 and 0 were used to determine ovulation in response to GnRH on d 5. Pregnancy was determined on d 32 and 60 and intervening pregnancy loss was calculated. Of those heifers in the 7D treatment having progesterone ≥1 ng/mL on d 7, the proportion having progesterone <1 ng/mL 2 d later (luteolysis) was greater (P < 0.05) than that in the 5D treatment (43.0 vs. 22.9%, respectively). Total proportion of follicles that ovulated per heifer was numerically greater in the 7D treatment but only differed (P < 0.05) between locations. A treatment x location interaction was detected for pregnancy rates per AI. The Kansas location had no detectable treatment differences. In contrast, the 7D treatment produced greater (P < 0.05) pregnancy rates in the first replicate of the Florida location and at the Mississippi location. We concluded that the 5D protocol was not effective in producing acceptable luteolysis, pregnancy, and ovulation rates in comparison with the modified 7D protocol.
138

Standardization of a flow cytometric technique for detection of anti-sperm antibodies in bulls.

Sardoy, Maria Clara January 1900 (has links)
Master of Science / Department of Clinical Sciences / Maria S. Ferrer / Presence of anti-sperm antibodies (ASA) is associated with infertility in many species, including bulls but there is no standardized direct technique that allows detection of ASA bound to the sperm surface. The overall objective was to standardize a flow cytometric technique for detection of IgG and IgA directly attached to bovine sperm. The effects of fixation using phosphate buffer solution (PBS) or diluted formalin buffer solution (dFBS), exclusion of dead cells from the analysis, and aliquot variability were assessed using healthy bulls classified as Satisfactory Potential Breeders (SPB, n=9) and bulls with experimentally induced ASA (n=4) (Experiment1). The effect of freezing on the percentage of IgG- and IgA- bound sperm was assessed in samples from immunized bulls (n=4) (Experiment 2). Anti-sperm antibodies on the sperm surface were induced in yearling bulls by intramuscular injection of autologous semen and an adjuvant. Fixation of sperm cells did not affect the percentage of IgG- or IgA-bound sperm in any group of bulls. Exclusion of dead cell from the analysis did not affect the percentage of IgG-bound sperm (p= 0.0922 and p= 0.1525 for immunized and reproductively normal bulls, respectively). The exclusion of dead cells significantly increased the percentage of IgA-bound sperm in semen samples from immunized bulls (p= 0.0152) and significantly decreased the percentage of IgA- bound sperm in semen samples from reproductively normal bulls (p= 0.0012). Variability was < 10% in samples from immunized and reproductively normal bulls for percentage of IgG- and IgA-bound sperm. Freezing did not affect the percentage of IgG- (p=0.1287) or IgA-bound sperm (p=0.4175). Based on these results, fixation is neither necessary nor detrimental for analysis, and the percentage of antibody-bound cell should be calculated gated on the population of live cells only, especially when evaluating IgA binding. The percentage of ASA-bound sperm can be assessed on frozen-thawed samples. The development of this technique allows for further studies on ASA-bound sperm in populations of normal and abnormal bulls.
139

The effects of dosing feedlot cattle with Megasphaera elsdenii strain NCIMB 41125 prior to the introduction of a grain-rich diet

McDaniel, Michael Reid January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / James S. Drouillard / Two experiments were conducted to evaluate the efficacy of [italic]Megasphaera elsdenii[italic] strain NCIMB 41125 and its potential use in the mitigation of ruminal acidosis. In experiment 1, a metabolism study was conducted to evaluate ruminal parameters, quantify changes in ruminal bacterial populations, and determine in vitro capacity for lactate utilization following intraruminal dosing of a placebo or [italic]M. [italic]elsdenii strain NCIMB 41125 and an abrupt diet change. Angus crossbred steers (n=20; average BW=253 ± 24 kg) fitted with ruminal cannulas were blocked by BW and assigned randomly to treatments. Treatments consisted of intraruminal dosing with a placebo (100 mL of autoclaved culture), or 10, 100, or 1,000 mL of a live culture containing 1.62×108 CFU/mL of [italic]M. elsdenii[italic] strain NCIMB 41125. Prior to inoculation, cattle were placed into individual pens in an enclosed facility and allowed free access to alfalfa hay, salt, and water. Feed and water were removed for 24 h prior to administering treatments, after which, cattle were allowed free access to a diet consisting of 34% alfalfa hay and 66% steam-flaked corn-based concentrate. On d 7, cattle were fed an 80% concentrate diet. On d 12, steers were started on the final finishing diet of 94% concentrate. Ruminal pH and concentrations of lactate and VFAs were monitored following introduction of each concentrate diet. Ruminal samples were collected at 0, 2, 4, 6, 8, and 24 h after feeding for quantitative rt-PCR detection of native and introduced strains of [italic]M. elsdenii[italic], as well as total bacterial genomes. Capacity for metabolism of lactic acid was evaluated by inoculating 0.2 mL of strained ruminal fluid into anaerobic culture tubes containing 15 mL of semi-defined lactate medium. Tubes were incubated at 39˚C, and turbidity changes were determined by measuring absorbance at 2 h intervals up to 12 h. Experiment 2 was conducted in a commercial feedlot to evaluate the efficacy of [italic]M. elsdenii[italic] strain NCIMB 41125 for improving feedlot performance. A second objective of the study was to determine if oral dosing of [italic]M. elsdenii[italic] has the potential for reducing the number of cattle treated for bovine respiratory disease. Angus steers and heifers (n = 3179; average BW = 356 ± 58.4kg) were used in a randomized complete block design with two treatments. Cattle were assigned to treatment on an every-other-head basis such that every-other-animal was orally drenched with 100 mL of a culture medium containing 1.5×108 cfu/mL [italic]M. elsdenii[italic] strain NCIMB 41125 at processing. Cattle were blocked by gender and date of arrival. To maximize profitability, cattle were sorted via visual appraisal to identify cattle that were market ready. Cattle were shipped to a commercial abattoir in Lexington, NE for harvest. Data obtained for each pen of cattle included feedlot performance, morbidity, mortality, carcass characteristics, and grid-based program carcass qualifications. In trial 1, compared to the placebo group, cattle administered [italic]Megasphaera[italic] maintained higher ruminal pH 24 h after the carbohydrate challenge (P < 0.05). Ruminal lactate concentrations increased in response to the diet change (P < 0.05), but concentrations were lower for cattle that received [italic]Megasphaera[italic] compared to the placebo group (P < 0.05). Total number of bacterial genomes 24 h after inoculation was unaffected by intraruminal dosing of [italic]M. elsdenii[italic] strain NCIMB 41125 (P > 0.05), but populations of undifferentiated [italic]M. elsdenii[italic] and strain NCIMB 41125 increased by 24 h after inoculation (P < 0.05). Turbidity of cultures inoculated with ruminal fluid increased in response to [italic]M. elsdenii[italic] administration (P < 0.05), suggesting a greater capacity for lactate utilization in inoculated cattle compared to the placebo group. In trial 2, no differences in feed efficiency were observed (P > 0.05). Compared to cattle dosed with [italic]Megasphaera[italic], the control group had more USDA yield grade 2 carcasses (P < 0.05), and cattle dosed with [italic]M. elsdenii[italic] had more USDA yield grade 5 carcasses (P < 0.05). [italic]Megasphaera[italic] cattle also tended to have more USDA Prime carcasses (P = 0.14). No effects on incidence of liver abscesses were observed. Dosing cattle with [italic]M. elsdenii[italic] prior to introduction of typical concentrate diets may be useful in preventing ruminal lactate accumulation and associated depressions in ruminal pH. Inoculating cattle with [italic]M. elsdenii[italic] is effective in bolstering populations of ruminal lactate utilizers, and may be useful in preventing ruminal lactate accumulation in grain-fed cattle. No effects on reducing episodes of BRD were noted.
140

Inclusion of wet corn gluten feed with physically effective neutral detergent fiber and the resulting effects on production

Sullivan, Michelle Lea January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Barry J. Bradford / Wet corn gluten feed (WCGF) is commonly included in lactation rations for dairy cattle. Research at Kansas State University has shown that increasing WCGF inclusion decreased ruminal pH. Lack of adequate particle size may result in this decrease and can impact efficiencies, animal health and longevity. A study was conducted to look at the effects of feeding WCGF while maintaining > 10% of particles > 19 mm across diets. We hypothesized that as WCGF increased, DMI and milk yield would increase while ruminal pH would be maintained. Seven ruminally-cannulated, lactating Holstein cows were used in an incomplete 4 × 4 Latin square design with treatments of 0, 12.4, 24.5 or 35.1% WCGF across 4 periods of 21 d. Alfalfa hay was used to maintain particle size. All diets met particle size goals; however, as WCGF increased, the proportion of particles > 19 mm decreased (P = 0.01) and cows changed their sorting behavior in favor of particles > 19 mm (P = 0.03) and against particles on the bottom screen (P < 0.01) and pan (P = 0.01). As WCGF increased, ruminal pH and ECM/DMI were not affected, yet DMI (P = 0.02) and milk yield (P = 0.02) increased quadratically. Milk protein, lactose and fat concentrations were not affected; however, milk protein (P = 0.004; linear) and lactose (P = 0.02; quadratic) yields increased. In a separate study, active dry yeast (ADY) products, commonly used in the dairy industry to support ruminal health, were evaluated for product guarantees and effects of storage and storage medium. Few products received through normal distribution met product guarantees (1 of 6; experiment 1) and after 3 mo of storage cell viability dropped significantly (P < 0.01). In the second experiment, products were stored in ground corn or in a vitamin-trace mineral mix (VTM). Depressions in viability caused by high-temperature storage were partially mitigated when ADY products were stored with a VTM. Although both mediums resulted in lower cell viabilities after storage at 40ºC, VTM cell viabilities were significantly (P = 0.02) higher than ground corn.

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