Theses and Dissertations at Montana State University (MSU)
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Item Corn versus barley in beef cattle finishing diets: effect on steer performance, feeding behavior, and ruminal environment(Montana State University - Bozeman, College of Agriculture, 2021) DelCurto-Wyffels, Hannah Margaret; Chairperson, Graduate Committee: Megan Van Emon; Julia M. Dafoe, Cory T. Parsons, Darrin L. Boss, Timothy DelCurto, Samuel A. Wyffels, Megan L. Van Emon and Janice G. P. Bowman were co-authors of the article, 'Corn versus barley in finishing diets: effect on steer performance and feeding behavior' in the journal 'Animals' which is contained within this dissertation.; Julia M. Dafoe, Cory T. Parsons, Darrin L. Boss, Timothy DelCurto, Samuel A. Wyffels, Megan L. Van Emon and Janice G. P. Bowman were co-authors of the article, 'The influence of environmental conditions on intake behavior and activity by feedlot steers fed corn or barley-based diets' in the journal 'Animals' which is contained within this dissertation.; Hannah M. DelCurto-Wyffels, Julia M. Dafoe, Cory T. Parsons, Darrin L. Boss, Timothy DelCurto, Samuel A. Wyffels, Megan L. Van Emon and Janice G. P. Bowman were co-authors of the article, 'Diurnal ruminal pH and temperature patterns of steers fed corn or barley-based finishing diets' in the journal 'Animals' which is contained within this dissertation.While corn is the most common feed ingredient in the United States, barley, which is more suitable for the growing and climatic conditions at northern latitudes, can be a common feed alternative to corn. The different digestive utilization of unique feedstuffs coupled with extreme environmental conditions can pose challenges to efficiently feeding cattle in different climates. Thus, to further our understanding of the use of barley in feedlot diets at northern latitudes this study evaluated the effects of barley and corn finishing rations on feedlot performance, feeding behavior, and ruminal environment. For two consecutive years, Angus-based yearling steer calves were fed in a feedlot trial (427.3 + or - 3.7 kg; n = 48 in year 1, and 406.8 + or - 3.4 kg; n = 47 in year 2). Steers were randomly assigned to one of two primary basal grain dietary treatments: 1) Number 2 feed corn or 2) Hockett barley. Steers were fed in a GrowSafe system to measure individual animal intake and behavior throughout the duration of the study. Twelve steers per treatment group for each year of the study were also fitted with a HOBO pendent G accelerometer to measure activity and a SmaXtec ruminal bolus for continuous rumen monitoring of temperature and pH. Limited differences were observed in regard to performance and eating behavior of steers fed corn or barley-based diets. The steer's diet interacted with short term environmental changes to influence animal feeding behavior, but diet had limited impact on cattle lying activity. Continuous ruminal monitoring revealed average daily ruminal pH and temperature were not impacted by diet; however, diet did affect daily variation in ruminal pH and temperature. Intake patterns were also different between corn and barley-fed steers in which corn-fed steers consumed more feed the first 6 hours directly after feeding while barley-fed steers consumed more feed later in the day. Presumably, these intake patterns could be influenced by differences in diurnal patterns of ruminal pH between corn and barley. Depending on cost and production year, both barley and corn can be high quality feedstuffs to use in beef cattle finishing rations.Item Relationship between current temperament measures and physiological responses to handling of feedlot cattle(Montana State University - Bozeman, College of Agriculture, 2015) Williams, Andrew Fillmore; Chairperson, Graduate Committee: Jane A. BolesTemperament in beef cattle has become a research focus due to increasing consumer awareness of animal welfare. Researchers have defined temperament as behavioral responses to a perceived stressful event. "Fight-or-Flight" response is influenced by environmental and genetic factors including age, sex, and breed. Subjective chute scoring systems have been used by many researchers. Due to the subjectivity and associated variability among observers, chute scores have been questioned for repeatability and consistency. An alternative measurement currently used, is exit velocity or speed at which an animal exits a chute, and is recognized as the most practical objective measure for assessing temperament. Physiological markers used to evaluate temperament are increased blood cortisol and lactate concentrations. The first objective of this study was to compare temperament differences between feedlot steers and heifers. The second objective was to evaluate physiological measures taken chute side as potential markers for defining an animal's temperament and potential predictor. Pulse, oxygen saturation, rectal temperature, blood lactate, blood glucose and lactate concentrations, salivary cortisol, and serum cortisol were measured on mixed breed and sex feedlot cattle (n = 197), significant difference alpha = P< 0.05 . Exit velocities were used to classify animals as fast, medium, and slow, plasma lactate was significantly different between all classes. Exit velocity and physiological measures differed between sex. Heifers had higher exit velocities (P = 0.003), plasma lactate concentrations (p = 0.03), and cortisol concentrations (P = 0.001). Simple correlations among these variables showed rectal temperature (heifers r = 0.44, P <0.0001; steers 0.45 P < .0001), plasma lactate (heifers r = 0.52 P < 0.0001; steers r = 0.63 P < 0.0001), serum lactate (heifers r = 0.53 P < 0.001; steers r = 0.59 P < 0.001) and glucose (heifers r = 0.54 P < 0.001; steers r = 0.32 P <0.003) were all correlated to exit velocity in both sexes. Cortisol measures were not correlated to exit velocity in steers but were in heifers. Linear models were constructed and evaluated using Akaike information criterion, the top candidate model was plasma lactate in combination with body temperature to predict exit velocity.Item Site characteristics and effect on elk and mule deer use of the Gardiner winter range, Montana(Montana State University - Bozeman, College of Agriculture, 1984) McNeal, Allen FrancisItem Effect of mating system on selection response in Japanese quail(Montana State University - Bozeman, College of Agriculture, 1977) MacNeil, Michael DavidItem Training responses of two-year-old Quarter horses fed rapidly fermentable carbohydrates(Montana State University - Bozeman, College of Agriculture, 2009) Black, Wade Raymond; Chairperson, Graduate Committee: Janice G. P. Bowman.Two replicated experiments (Exp. 1: May 14 to June 8; Exp.2: June 25 to July 20) evaluated effects of feeding grain to 2-yr-old Quarter horses on behavior and physiological parameters during early stages of training. In each experiment, 6 different horses were allotted by sex and weight to 2 diets; hay only or hay plus 2.3 kg/d grain. Horses were group-housed with ad libitum access to grass/alfalfa hay and water, and were individually fed 1.15 kg grain or 40 g salt (placebo) at 0800 and 1600 for 7 d prior to and during training. The trainer was blind to diet assignments. Horses were trained 5 d/wk for 3 wk and scored (1 to 5) by the trainer daily on obedience (willingness to ride with a loose rein and little leg pressure), life (willingness to move at any desired speed), and direction (suppleness in the poll and loin), while an observer scored fearfulness. A heart monitor recorded minimum, maximum, and mean heart rate daily during training. Categorical data were transformed by subtracting the daily median as each horse's score was relative to the other horses on that day. Data were analyzed as repeated measures (Proc Mixed of SAS) with horse as the experimental unit. In Exp. 1 grain did not affect (P = 0.83) obedience, while horses fed grain in Exp. 2 were less obedient during training (P = 0.02) than those not receiving grain. Horses fed grain showed greater (P = 0.05) fearfulness than horses fed hay alone. Life:direction (ideal is 1.0, > 1.0 indicates high self-preservation) was higher (P = 0.04) in horses fed grain than in those fed hay alone (1.29 vs. 1.08, respectively). Maximum heart rate was not affected (P = 0.21) by grain, while mean heart rate was higher (P = 0.03) for horses fed grain than hay alone (126 vs. 119 beats/min, respectively). Horses fed grain during training exhibited more self-preservation behavior, increased mean heart rate, and an unbalanced life to direction ratio, which could inhibit training effectiveness.Item Sequential cattle and sheep grazing for Spotted Knapweed control(Montana State University - Bozeman, College of Agriculture, 2008) Henderson, Stacee Lyn; Chairperson, Graduate Committee: Rodney W. KottSpotted knapweed (Centaurea stoebe L.) infests millions of hectares of native rangeland in North America. Spotted knapweed creates large monocultures, which decreases biodiversity, reduces livestock and wildlife forage, and increases surface water runoff and soil erosion. Sheep are an effective tool for controlling spotted knapweed and have been widely used on cattle ranches for weed control. However, cattle producers are concerned that sheep will over-utilize desirable graminoids. Therefore, research is needed to determine an effective grazing strategy using cattle and sheep that will adversely affect spotted knapweed, while minimizing over-use of desirable graminoids across the landscape. This 2-year study quantified graminoid and spotted knapweed utilization and diet composition and foraging behavior of cattle and sheep sequentially grazing spotted knapweed-infested rangeland in western Montana. Twenty-one Targhee yearling wethers and 9 Black Angus yearling cattle were used. Animals were randomly assigned to one of 3, 0.81-ha pastures that were grazed in either mid-June or mid-July (n=6 pastures). Cattle grazed each pasture for 7 days, immediately followed by sheep grazing for 7 days in each month. Analysis of covariance was used to determine differences in diets, relative preference indices, foraging behavior, and utilization between June and July for cattle and sheep to determine the optimal month for implementing prescribed sheep grazing. Relative utilization of spotted knapweed did not differ between June and July and averaged 61.5%. Graminoid utilization was moderate (<45%). Cattle preferred forbs in June, spotted knapweed and forbs in July, and avoided graminoids in July. Sheep avoided graminoids in June and July, preferred forbs in June, and showed no preference or avoidance of spotted knapweed. Cattle ranches with large spotted knapweed infestations can effectively use prescribed sheep grazing immediately following cattle grazing in June or July to achieve high levels of use on spotted knapweed, thus reducing viable seeds incorporated into the soil, while maintaining optimal utilization levels on desirable graminoids.