Master of Science / Department of Animal Sciences and Industry / KC Olson / Our objective was to determine the effects of supplemental corn steep liquor (CSL) on voluntary selection of sericea lespedeza (SL) by beef cows grazing native tallgrass range. Dietary botanical composition of cows (n = 145; initial BW = 579 ± 91 kg) was evaluated during a 150-d grazing period (5/1 to 10/1). Native pastures (n = 9; 50 ± 17 ha) infested by SL (average SL biomass = 37% of total forage biomass) were assigned randomly to 1 of 2 treatments: grazing by unsupplemented cows or grazing by cows supplemented with CSL (1.79 kg DM • cow-1 • d-1; 45% DM, 34% CP). Cows were assigned randomly to treatment and pasture (stocking rate = 0.5 ha/AUM). Concentration and protein-binding capacity of condensed tannins (CT) in SL were measured monthly. Fecal samples were collected from each cow on 6/1, 7/1, 8/1, 9/1, and 10/1. Herbivory of SL was estimated along line transects in October. Plant fragments in fecal samples were quantified via a microhistological technique; fragment prevalence in fecal material was assumed to equal botanical composition of the diet. Concentration and protein-binding capacity of CT in SL were greatest (P < 0.01) on 8/1 and 9/1, respectively. The proportion of individual SL plants showing evidence of herbivory tended to be greater (P = 0.09) on pastures grazed by supplemented cows compared to pastures grazed by unsupplemented cows (94 vs. 80% of SL stems, respectively). Prevalence of SL in beef cow diets was influenced (P < 0.01) by CSL supplementation and by month. Prevalence of SL in beef cow diets was not different (P ≥ 0.35) between treatments when concentration and protein-binding capacity of CT were relatively low (6/1, 7/1, and 10/1). In contrast, supplemented cows selected more (P < 0.01) SL than unsupplemented cows when concentration and protein-binding capacity of CT were greatest (8/1 and 9/1). We interpreted these data to suggest that voluntary selection of SL by beef cows was inversely related to concentration of CT; moreover, supplemental CSL stimulated voluntary selection of SL during periods of high CT concentration. Supplemental CSL did not influence selection of other plant species that were monitored.

Master of Science / Department of Animal Science and Industry / R. L. Weaber / This thesis includes two studies that assessed the relationships between docility and reproduction in Angus heifers, both from a phenotypic and genetic standpoint. The objective of the first study was to elucidate the phenotypic relationships between docility and first service AI conception rate in heifers. Data (n = 337) included exit velocity (EV), chute score (CS), fecal cortisol (FC), and blood serum cortisol (BC). Statistical analysis was done using logistic regression with 30 day pregnancy rate as the dependent variable. The model included the fixed effect of contemporary group, and the covariates FC, BC, EV, CS, weight, and age. Correlation coefficients were also calculated between all continuous traits. The power of our test could not detect any significant predictors of 30 d pregnancy for the combined data from all ranches. The objective of the second study was to determine the genetic control of docility and reproduction in heifers as measured by pregnancy rate. A subjective chute scoring system was used as the basis of their genetic evaluation for docility. Pedigree information was obtained on approximately 508,015 animals over 30 generations. Data included approximately 26,878 records on heifer pregnancy and 113,412 records on docility, with 7,849 animals having both docility and heifer pregnancy records. Contemporary groups were formed by the concatenation of weaning contemporary group, yearling contemporary group, and breeding contemporary group. Heritabilities were calculated from estimates of genetic and residual variance components computed using ASReml 3.0 (VSN International; Hemel Hempstead, UK). Heifer pregnancy variance components were estimated from a univariate, threshold model, with pregnancy outcome as the dependent variable. Animal and contemporary group were fit as a random effects, while age at first breeding was fit as a covariate. The heritability of heifer pregnancy was estimated to be 0.16 ± 0.02. Docility was fit as a univariate, linear animal model with docility score as the dependent variable. Animal and contemporary group were both modeled as random effects. The heritability for docility score was estimated to be 0.22 ± 0.03. Fertility is a complex trait that is dependent on many factors; our data suggest that docility is one factor that warrants further investigation.

Master of Science / Department of Animal Sciences and Industry / Barry Bradford / During the transition period, 3 wk before to 3 wk after calving, dairy cows experience a variety of sudden hormonal and metabolic shifts that could result in metabolic disorders or diseases, which can be detrimental to the productive life and longevity of the cow. Cows undergo a negative energy balance, where they cannot consume enough feed to meet their energy requirements. To make up this deficit, cows mobilize adipose tissue in the form of non-esterified fatty acids (NEFA) which are transported to the liver and are either used for fuel or stored as triglycerides. High levels of circulating NEFA can lead to endoplasmic reticulum (ER) stress, which is linked to inflammation. This low-grade inflammation can compromise cell function. To mitigate this inflammation, sodium salicylate, a non-steroidal anti-inflammatory drug (NSAID), was given to mature (3+ parity) cows for 7 d after parturition via their drinking water. Blood was collected daily and a glucose turnover assay was performed. Liver, muscle, and adipose tissue was collected on d 7. Overall, it appeared that SS increased insulin sensitivity and depressed gluconeogenesis post-transcriptionally. Multiple in vitro studies were performed on immortalized bovine mammary epithelium (MAC-T) cells to determine the action of SS when ER stress was induced with palmitate (PALM). Treatment with SS did not mitigate, and in some cases exacerbated, the ER stress response. The addition of bovine serum albumin (BSA), a common component of cell culture media, may alter reactive oxygen species (ROS) measurements due to its antioxidant property. Overall, SS seems to alter metabolic processes and the cellular response to stress.

Master of Science / Department of Animal Sciences and Industry / Joel M. DeRouchey / Five experiments used 3,004 pigs to determine influences of wheat middlings (Midds), dried distillers grains with solubles (DDGS), and choice white grease (CWG) on growth, carcass traits, and carcass fat quality of finishing pigs and the optimal SID Trp:Lys in growing and finishing pigs fed 30% DDGS. In Exp. 1, pigs fed increasing dietary Midds had decreased (linear; P≤0.02) ADG and G:F. Feeding 30% DDGS did not influence growth performance. For carcass traits, increasing Midds decreased (linear; P<0.01) carcass yield, HCW, and backfat depth (quadratic; P<0.02) but increased (quadratic; P<0.01) FFLI. Feeding 30% DDGS decreased (P<0.03) carcass yield and backfat depth (P<0.01), but increased FFLI (P<0.02) and jowl fat IV (P<0.001). In Exp. 2, feeding 20% dietary Midds decreased (P<0.01) ADG and G:F. Pigs fed diets with increasing CWG had improved ADG (quadratic, P<0.03) and G:F (linear, P<0.01). Dietary Midds or CWG did not affect ADFI. For carcass traits, feeding 20% Midds decreased carcass yield (P<0.05), HCW, backfat depth, and loin depth, while increasing jowl fat IV (P<0.001). Pigs fed CWG also had decreased (linear, P<0.05) FFLI and increased (linear, P<0.01) jowl fat iodine value. In conclusion, feeding Midds reduced pig growth performance, carcass yield, and increased jowl fat IV. In Exp. 3, xylanase supplementation did not improve growth performance or carcass traits of pigs fed different dietary energy and fiber levels. Increasing dietary energy increased (linear; P<0.001) ADG and G:F with no affect on ADFI. Increasing dietary energy increased (linear; P<0.01) yield, HCW, backfat depth, and reduced FFLI (linear; P<0.001) and jowl fat iodine value (linear; P<0.001). Apparent total tract digestibility of ADF improved (P<0.002) with the addition of dietary xylanase; however, there were no differences in any other nutrient digestibility criteria. As dietary energy increased, there was an increase (linear; P<0.02) in apparent digestibility of DM, N, fat, GE, ADF, and NDF. In Exp. 4 and 5, results indicated the optimal SID Trp:Lys was 16.5% from 36.3 to 72.6 kg, but at least 19.5% from 72.6 to 120.2 kg in corn-soybean meal diets containing 30% DDGS.

Master of Science / Department of Animal Sciences and Industry / Janice C. Swanson / Canine thunderstorm phobia is a common, frustrating, and complex problem that, due to the often severe nature of the clinical signs, can lead to canine relinquishment to shelters. Although a potentially treatable disorder, existing treatment options have several limitations and variable success rates. Three survey-based studies were conducted to increase the knowledge base for canine thunderstorm phobia. The first study distributed 1445 surveys through 16 Kansas veterinary clinics to determine the prevalence and characteristics of thunderstorm phobic dogs and assess differences between affected and non-affected dogs. Of 463 dogs surveyed, 240 were thunderstorm phobic as assessed by their owners. Severe weather warning systems may play a role in thunderstorm phobia. Thunderstorm phobic dogs were more fearful when exposed to tornado sirens, both during actual storms and siren testing, indicating a possible effect of classical conditioning. No differences were noted regarding sex, breed, pedigree, or neuter status. Most affected dogs preferred to be indoors remaining near their owners. The second study distributed 1600 surveys through eight Kansas animal shelters to determine the prevalence of relinquished dogs with thunderstorm phobia. Other reasons for relinquishment were also assessed. A fear of thunder was among the least common behavioral problems leading to relinquishment in dogs. Only a quarter of owners had visited a veterinarian for assistance with behavioral problems. The third study involved the administration of dog appeasing pheromone (DAP) in a double-blind, placebo-controlled, randomized clinical trial to assess its efficacy as a sole treatment for thunderstorm phobia. Data was collected from 60 dog owners using behavioral assessment questionnaires. In dogs given the placebo, six behaviors significantly improved, with another eleven showing a numerical trend toward improvement. However, in dogs given DAP, significant improvement was seen in three of these same behaviors. Consequently, these results do not indicate the potential use of DAP for reducing fearful behaviors associated with thunderstorm phobia when compared to negative controls. Information gained from these studies allows veterinarians and behavioral researchers to better understand the extent of this behavioral disorder and hopefully stimulates future research to find new and more effective ways to treat it.

Master of Science / Department of Animal Sciences and Industry / Robert D. Goodband / A total of 5,480 pigs involving 10 experiments were conducted. Experiment 1 evaluated 3 feeder gap settings: 1.27, 1.91, or 2.54 cm, while Exp. 2 evaluated the effects of feeder trough space (4.45 vs. 8.9 cm/pig) and minimum feeder gap opening of 1.27 vs. 2.54 cm. In Exp. 1, pigs fed with increasing feeder gap had decreased (linear; P < 0.03) G:F due to increased (linear; P <0.02) ADFI. In Exp. 2, there was a tendency (P = 0.08) for increased ADG as feeder trough space increased from 4.45 to 8.9 cm/pig. Pigs fed with the wide feeder gap setting had increased (P < 0.01) ADFI and decreased (P < 0.01) G:F compared to pigs with the narrow feeder gap setting. Experiments 3 and 4 were conducted to determine the effects of diet form (meal vs. pellet) and feeder design (conventional dry vs. wet-dry) on finisher pig performance. In Exp. 3, pigs fed pelleted diets or via a wet-dry feeder had greater (P < 0.07 and 0.01, respectively) ADG then those fed meal diets or with a dry feeder. Diet × feeder interactions (P < 0.02) were observed for G:F. When pelleted diets were presented in dry feeders, G:F decreased, while no difference in G:F was observed between meal and pelleted diets presented in wet-dry feeders. In Exp. 4, pigs fed with wet-dry feeders had increased (P < 0.02) ADG and ADFI compared to those with dry feeders, while pigs presented pelleted diets had improved (P = 0.05) G:F compared to those presented meal diets. Experiments 5 to 9 were conducted to determine the effects of porcine intestinal mucosa products, PEP2+, Peptone 50, and PEP-NS, on the growth performance of nursery pigs. In Exp. 5, pigs fed increasing PEP2 had increased (quadratic; P < 0.02) overall ADG, ADFI, and G:F with the greatest response observed at 4% PEP2. In Exp. 6, pigs fed PEP2 had improved (P < 0.03) G:F compared to pigs fed select menhaden fish meal (SMFM) and increasing PEP2 improved (quadratic; P < 0.04) G:F with the greatest improvement seen when diets contained 4% PEP2. In Exp. 7 pigs fed PEP2+, Peptone 50 and PEP-NS had increased (P < 0.05) ADG and ADFI compared to pigs fed a negative control diet. In Exp. 8, pigs fed diets containing 6% SMFM, PEP2+, or PEP-NS had improved (P < 0.05) ADG and ADFI compared to pigs fed the negative control or 6% Peptone 50. In Exp. 9, pigs fed increasing PEP-NS had improved (quadratic; P < 0.01) ADG and G:F, with the greatest improvement observed in pigs fed 6% PEP-NS. Experiment 10 evaluated the effects of Liquitein and PCV2/M. hyo vaccine regimen on the growth performance of weanling pigs. Overall, there were no effects of Liquitein on growth performance and vaccinated pigs had decreased (P < 0.01) ADG and ADFI compared to non-vaccinated pigs.

Master of Science / Department of Animal Sciences and Industry / R. Scott Beyer / Over the decades much has been discovered about the appropriate lighting management strategies for raising commercial meat-type poultry. Our knowledge of light preference, wavelength, intensity, intermittent lighting, and avian spectral sensitivity continues to improve our management strategies. In this work, a total of 5 experiments were conducted. The first 2 experiments investigated the effects of Light emitting diodes (LED) lights on growth performance of broiler chicks. Broiler chicks were raised under LED lights at different intensities: 5, 10, 15, 20, and 25 lux. A significant linear relationship (P < 0.05) was found in experiment 1 between body weight gain and light intensity. In experiment 2, a linear trend was noticed between body weight gain and light intensity. As the light intensity increased, chick weight increased. Feed: gain ratios were not affected by light intensity. The third experiment also examined growth performance using LED lighting as well as the effects of feed form and different lighting intensities upon behavior. The broilers fed a pelleted diet had significantly better performance than those fed crumbles. Under more intense light it was discovered that broilers spend significantly more time (P< .05) consuming feed compared to dim light. The fourth experiment focused on broiler preference for light color, and feed form during feeding. The broilers were offered either pelleted or crumbled feed and served under 4 different light colors: red, white, blue, and green. It was found that broilers statistically preferred pelleted feed, and white lighting, with red being the 2nd color choice of preference while green and blue were statistically not chosen. The fifth experiment focused on chick preference for feed color, when under different light color. One day old chicks were offered dyed feed: red, yellow, blue, green or light brown iv (control) under 5 different colors of light: red, yellow, blue, green, and white. It was found that chicks significantly preferred red dyed feed, especially under blue light. In conclusion, it was found that LED lights can have positive effects on broiler performance. Broilers show a preference for white lighting and pelleted feed. Young chicks show a preference for red dyed feed.

Master of Science / Department of Animal Sciences and Industry / R. Scott Beyer / Three experiments were conducted to evaluate the effects of gelatinized starch created during the pelleting process. Effects of gelatinization were first broadly tested to find if either increased or decreased gelatinization levels would increase broiler weight gain and feed efficiency during the starter period, 0 to 21 days of age. Results of the first experiment indicated a decrease (P<0.05) in broiler performance with increased levels of gelatinization, and a significant effect when the inclusion of gelatinized starch in the diet increased from 0 to 35%. A second experiment was conducted using a smaller range, 0 to 21% versus 0 to 35% inclusion of gelatinized starch in the diet and a smaller increment of increase, 3 versus 5%. Results of this experiment confirmed the results of the first experiment, and regression analysis was performed on the data. A linear decrease in body weight gain and quadratic increase in feed:gain (P<0.05) was observed as gelatinized starch was increased from 0 to 21% of the diet. A survey of the literature was conducted showing that most of the simulated levels of gelatinization were larger than those achieved with typical pelleted broiler diets. A third experiment was designed to investigate the levels of gelatinization observed in a pelleted diet and combined with three corn particle sizes, small (466 μm), medium (878 μm), and large (1240 μm), to find if any interactions existed. Chicks fed with the highest gelatinization level of 20%, (7.86% inclusion of pregelatinized starch) had lower body weight gains (P<0.05), and higher feed:gain (P<0.05) compared to chicks fed with 0% gelatinization. Small particle size had the lowest live body weight gain and lowest pen feed intake (P<0.05). There were no interactions found between gelatinization level and particle size (P>0.10). The results demonstrated a negative effect on chick body weight gain and feed efficiency by gelatinization of starch.

Doctor of Philosophy / Department of Animal Sciences and Industry / Evan C. Titgemeyer / Two experiments were conducted to evaluate the effects of late gestation and early lactation on the nutritional status of beef heifers fed low-quality, warm-season grass hay. The first experiment compared DMI, DM digestibility, and ruminal dynamics of pregnant and lactating beef heifers to non-gestating, non-lactating heifers of a similar age and size. This study demonstrated that pregnant heifers ate less than non-pregnant heifers while maintaining similar digestibilities. Intake was similar between lactating and non-lactating, though DM digestibility increased postpartum in lactating heifers. Ruminoreticular fill was less for pregnant than for non-pregnant heifers; ruminoreticular fill was similar regardless of lactation status. Ruminal NH3 increased with increasing intakes throughout the study. Lactating heifers had less ruminal NH3 than non-lactating heifers. Total ruminal VFA concentration was similar from 10 wk prepartum through 10 wk postpartum except at 2 wk prepartum when gestating heifers had less total ruminal VFA concentration. The second experiment compared DMI, DM digestibility, passage rate, and plasma glucose and BHBA concentrations between pregnant heifers, pregnant cows, lactating heifers, and lactating cows which were fed low-quality, warm-season grass hay supplemented with 450 g/d of soybean meal. This study demonstrated that DMI increased with progressing gestation in heifers. Lactating heifers had greater intake than other groups postpartum. DM digestibility decreased with advancing gestation; gestating animals had greater digestibility than non-gestating animals. Lactation status did not influence DM digestibility, though lactating heifers had greater digestibility from 3 to 7 wk postpartum. Digestibility was not influenced by age. Pregnant animals had faster digesta passage rates than non-pregnant counterparts. Plasma glucose concentration increased during the prepartum period; pregnant and lactating animals had lesser plasma glucose concentrations than non-gestating, non-lactating animals. Plasma BHBA concentration was greater in pregnant and lactating animals than in non-pregnant and non-lactating animal; age was not an influence on BHBA concentration. Calves from mature cows grew faster than calves from heifers. These studies showed that beef heifers do not have the same patterns of intake as mature cows during late gestation. Heifers and their calves exhibited poorer performance when compared to mature cows when fed low-quality, warm-season grass hay.

Master of Science / Department of Animal Sciences and Industry / J.S. Drouillard / Three studies were conducted to investigate alternative ingredients and processing methods for manufacturing low-moisture blocks. Study 1 was designed to determine if ruminal lactate could be transiently increased by feeding fructose-based blocks to heifers fed prairie hay, thus providing substrate for establishment of lactate utilizing microbes. Low-moisture blocks comprised of 96% fructose and 4% vegetable oil (DM basis) were manufactured and dosed via ruminal fistulas. Administration of fructose blocks resulted in transient increases in ruminal lactate (P < 0.05), accompanied by transient decreases in pH (P < 0.05). Ruminal fluid incubated with semi-defined lactate medium became more turbid (P < 0.05) as a result of prior exposure to fructose blocks suggesting greater capacity for lactate metabolism. In study 2 a portion of the molasses was replaced by corn steep liquor (CSL) or condensed corn distiller’s solubles (CCDS). Heifers were fed a forage-based diet and supplemented with 1 of 4 supplement blocks. Supplements were a 30% CP molasses block manufactured at ambient pressure and high temperatures (Mol-30). The remaining treatments were manufactured at reduced pressure and temperature and were a 30% CP block with 36% CSL (CSL-30); a 40% CP block with 40% CSL (CSL-40); or a 40% CP block with 25% CCDS (CCDS-40). Supplementing with Mol-30 and CSL-40 resulted in greater DMI (%BW) than with CCDS-40 (P < 0.05). Supplementing with CSL-30 improved efficiency and ADG compared to Mol-30 (P < 0.01). Study 3 evaluated the affect of cooking temperature on blocks containing CSL fed to heifers receiving a forage-based diet. Heifers were offered no supplement (Control) or a 15% CSL block manufactured at ambient pressure and high temperature (HT-15). The remaining treatments were manufactured at reduced pressure and temperature and were a 15% CSL block (LT-15); or 40% CSL block (LT-40). Control heifers had the lowest DMI and LT-40 had the greatest (P < 0.05). Feeding heifers LT-15 or LT-40 improved ADG compared to heifers fed HT-15 or no supplement (P < 0.05). Heifers fed LT-40 tended to be more efficient than those fed HT-15 and Control (P = 0.07).