Theses and Dissertations at Montana State University (MSU)
Permanent URI for this collectionhttps://scholarworks.montana.edu/handle/1/733
Browse
36 results
Search Results
Item Supplement intake behavior of heifers grazing late summer dryland pasture(Montana State University - Bozeman, College of Agriculture, 2022) McClain, Tyrell Phillip; Chairperson, Graduate Committee: Timothy DelCurto; This is a manuscript style paper that includes co-authored chapters.Two studies were conducted to evaluate supplement intake and intake behavior of Rumax BoviBox protein supplements. For both studies, individual supplement intake, time spent at the feeder, and frequency of visits was measured using a SmartFeed Pro self-feeder system. In study 1, we examined the effects of free choice loose mineral salt on protein block supplement intake behavior of first-calf heifers. Heifers were stratified by weight, and, within stratum, randomly allotted to one of two supplementation treatments: 1) free-choice access to protein block supplement (30% CP) with access to loose mineral and salt; and 2) free-choice access to protein block supplement (30% CP) with no access to loose mineral and salt for a 42-day performance study. Individual animal was considered the experimental unit. No differences were observed for total supplement intake or supplement intake expressed as grams per kg body weight (BW; P > 0.05). In summary, availability of loose mineral salt did not have an impact on protein block supplement intake. In study 2, we evaluated Rumax BoviBox versus Rumax BoviBox HM protein supplements on supplement intake, intake behavior, body weight (BW), and body condition score (BCS) change of yearling heifers grazing dryland pastures during late summer. Heifers (428 kg) were stratified by BW and within stratum randomly assigned to one of two supplementation treatments: 1) free-choice access to Rumax BoviBox protein block supplement (30% CP, 23% salt; n = 29); and 2) free-choice access to Rumax BoviBox HM high magnesium protein block supplement (28.7% CP, 23% salt; n = 30). Supplement intake rate (g x min -1) displayed a treatment effect (P < 0.01) indicating that heifers in the Rumax BoviBox treatment had lower intake rate compared to Rumax BoviBox HM supplemented heifers. In conclusion, there were only minor differences in intake behavior and animal performance observed in both trials.Item Evaluation of sustained release mineral boluses as a long-term nutrient delivery method for beef cattle(Montana State University - Bozeman, College of Agriculture, 2021) Carlisle, Tanner Jay; Chairperson, Graduate Committee: Timothy DelCurto; Samuel A. Wyffels, Steve D. Stafford, Anna R. Taylor, Megan L. Van Emon and Timothy DelCurto were co-authors of the article, 'Evaluation of sustained release mineral boluses as a long-term nutrient delivery method for beef cattle' in the journal 'Animal feed science and technology' which is contained within this thesis.Two studies were conducted to evaluate the efficacy of sustained release mineral boluses as an alternative nutrient delivery method for beef cattle. For both studies 16 ruminally-cannulated cows were used in a completely randomized design. In study 1, we evaluated degradation rates of two bolus prototypes and cow age (2-yr-old versus 3-yr-old cows) over an 87-d study period. In study 2, we evaluated two bolus types (90-d degradation target versus 180-d degradation target), as well as two diet qualities contrasting low-quality high-fiber forage (> 65% NDF and < 8% CP) and high-quality low-fiber forage (< 55% NDF and > 15% CP). For both Studies intake and digestion periods were conducted to evaluate cow age (study 1) or diet quality (study 2) effects on intake and rumen/reticulum function. In study 1, models containing an asymptotic effect of day and an interaction between day and bolus type received virtually all support of candidate models for bolus degradation rate. Cow age did not affect bolus degradation rates (Beta = -0.81 + or - 1.13; P= 0.48) and degradation rates were greater for bolus prototype B compared to bolus A (Beta prototype B = -20.39 + or - 1.13; Beta prototype A = -9.64 + or - 0.81; P < 0.01). In study 2, models containing a linear effect of day and an interaction between day and diet received virtually all support of candidate models for the degradation rate of the 90-d and 180-d prototype. In addition, both bolus protoypes displayed a diet quality + or - time interaction (P < 0.01) for bolus degradation rate. Cattle treated with the 90-d bolus and fed a high-quality diet had greater degradation rates (Beta High-quality = -2.64 + or - 0.08; Beta Low-quality = -1.97 + or - 0.10; P < 0.01) than the cows that were fed a low-quality diet. In contrast, cattle treated with the 180-d bolus expressed greater degradation rates (Beta Low-quality = -0.09 + or - 0.007; Beta High-quality = -0.04 + or - 0.005; P < 0.01) with cows on the low-quality diet versus the high-quality diet. Across both studies, two of four bolus prototypes met target release rates at 90 days. However, bolus degradation characteristics varied and were influenced by diet quality.Item Serum mineral concentrations in weaned Montana ram lambs and effects of dietary zinc source and concentration on developing Targhee rams(Montana State University - Bozeman, College of Agriculture, 2017) Page, Chad McBride; Chairperson, Graduate Committee: Tom Murphy; T. W. Murphy, M. L. Van Emon, J. G. P. Bowman, S. A. Wyffels and W. C. Stewart were co-authors of the article, 'Survey of serum trace mineral concentration in weaned Montana ram lambs: implications for trace mineral supplementation in weaned rams' submitted to the journal 'Journal of animal science' which is contained within this thesis.; M. L. Van Emon, T. W. Murphy, C. K. Larson, J. G. Berardinelli, I. R. McGregor and W. C. Stewart were co-authors of the article, 'Effects of zinc source and dietary concentration on zinc status, growth performance, wool traits, and reproductive characteristics in developing rams' submitted to the journal 'Journal of animal science' which is contained within this thesis.Trace mineral deficiencies exist in livestock operations and can contribute to decreased productivity and profitability. The objective of the first study was to quantify serum trace mineral concentrations in weaned ram lambs, with particular emphasis on Se and Zn. Serum samples (n = 221) were collected from ram lambs at 21 ranches throughout Montana and analyzed for Co, Cu, Fe, Mn, Mo, Se, and Zn concentrations. Additionally, water samples were analyzed for pertinent characteristics. Of ranches surveyed, only 67% provided a complete mineral supplement. Sheep that were provided supplementary trace mineral had greater serum Se concentrations (P < 0.001). Based on serum trace mineral concentration reference ranges, the two most commonly deficient and marginally deficient minerals across Montana were Se (19 and 23.8% of ranches, respectively) and Zn (9.5 and 57.1%, respectively). Of ranches sampled, 40 and 35% of water samples exceeded excessive concentrations in Na and sulfates, respectively. This regional knowledge of serum trace mineral concentrations in a sample of ram lambs can provide information for ranches to evaluate current and future mineral supplementation needs, as well as aid the feed industry in designing formulations for mineral premixes. Based on these results, a second study was designed with the objective to evaluate the effects of dietary Zn source and concentration on serum Zn status, growth performance, wool traits, and reproductive characteristics of developing yearling rams. Forty-four Targhee rams were used in an 84-d completely randomized design and were fed one of three pelleted dietary treatments: 1) a control diet without fortified Zn; 2) a diet fortified with a Zn amino acid complex (ZnAA); and 3) a diet fortified with ZnSO4. Serum samples were collected from each ram at four time periods to quantify serum Zn and testosterone concentrations. ZnSO4 had greater (P < or = 0.03) serum Zn concentrations compared to other treatments. Rams consuming ZnAA had greater (P < or = 0.03) average daily gain than rams in the other treatments. Wool regrowth was greater (P < 0.001) in the ZnSO4 treatment group compared to control. These results indicate that source and concentration of a Zn supplement appears to affect ram development.Item Does calcium propionate elicit similar growth and reproductive responses as monensin in developing heifers?(Montana State University - Bozeman, College of Agriculture, 2017) Hubbard, Ashton Rose; Chairperson, Graduate Committee: Rachel L. Endecott; C. C. Reichhardt, A. R. Williams, I. R. McGregor, C. M. Page, D. M. Staudenmeyer and R. L. Endecott were co-authors of the article, 'Does calcium propionate elicit similar feed efficiency and reproductive responses as monensin in developing heifers?' submitted to the journal 'Journal of animal science' which is contained within this thesis.Replacement beef heifer development is critical for the continued production of beef and for ranch success. Objectives of this research were to investigate the growth and reproductive responses of developing heifers fed similar basal diets supplemented with pellets containing different feed additives. Pellet treatments consisted of 2.27 kg x heifer -1 x d -1 of: 1) control with no feed-additive (CON), 2) 200 mg x heifer -1 x d -1 monensin (MON), or 3) 40 g x heifer -1 x d -1 calcium propionate (PRO). Experiment 1 utilized one hundred and ninety-eight heifers (254 + or = 3.8 kg) stratified by BW and randomly assigned to one of six pens (n = 2 pens per treatment). Experiment 2 utilized fifty-eight heifers (304 + or = 3.4 kg) stratified by BW and randomly assigned to one of 12 pens (4 pens per treatment). Heifers were fed a grass hay basal diet in both experiments (Exp. 1: 65% TDN and 11% CP; Exp. 2: 62% TDN and 15% CP, DM basis). Experiment 1 was 129 d and Experiment 2 was 122 d. Body weights were collected at the beginning and end of each experiment, with interim BW collected every 30 d. Serum samples were collected via coccygeal venipuncture and analyzed for progesterone to determine pubertal status. Overall pregnancy rates and pregnancy rate from AI were determined. Experiment 1 observed no differences for initial BW, final BW, overall ADG, pregnancy rate from AI, or overall pregnancy rate (P > or = 0.16). Fewer CON and PRO heifers were pubertal at experiment start than MON heifers (P < or = 0.01) in Experiment 1, which was unexpected. Differences in puberty achievement were diminished at the end of the experiment. Experiment 2 observed no differences for initial BW, final BW, overall ADG, pregnancy rate from AI, or overall pregnancy rate (P > or = 0.19). Treatment had no effect on puberty achievement at beginning or end of experiment (P > or = 0.09). A period effect was observed for ADG in both experiments (P < or = 0.01) which may be related to cold stress. Neither calcium propionate nor monensin resulted in improved performance compared to no feed additive. Further research is warranted to elucidate the impact of calcium propionate on heifer development.Item Cobalt supplementation affects humoral immune response in beef calves(Montana State University - Bozeman, College of Agriculture, 2015) Sager, Robert Bascom; Chairperson, Graduate Committee: Glenn Duff; Glenn C. Duff and Carl J. Yeoman were co-authors of the article, 'Cobalt supplementation in pre-weaned calves affects humoral immune response and feedlot health' in the journal 'Proceedings, western section, American Society of Animal Science' which is contained within this thesis.Economic losses from morbidity and mortality associated with bovine respiratory disease (BRD) in beef cattle are approaching $2 billion annually in the United States. Incidence and severity of BRD is increasing despite advances in animal health programs in prevention and treatment compared to twenty years ago. Mineral supplementation during pre-weaning has potential to reduce sickness and improve health. Cobalt (Co) is used by rumen-inhabiting microbes for the production of vitamin B 12. Vitamin B 12 is a cofactor for vital metabolic pathways in tissue carbohydrate and lipid metabolism required for maintenance and growth. Vitamin B 12 is also vital for B-cell proliferation to form plasma cells that secrete antibodies. National Research Council (NRC) recommendations for Co are 0.1 ppm (0.1 mg/kg; DM dry matter basis). Beef production has changed tremendously since NRC recommendations were set in the 1950's. The hypothesis of these three studies is NRC Co concentrations need to be increased to meet today's beef cattle metabolic requirements and production needs. The objectives of these studies were to evaluate if an orally-supplied Co dosed at nursing, pre-weaning, or post weaning affects humoral immune response during the post-weaning feeding period and reduces the incidence of BRD. Mannheimia haemolytica is a major pathogen of BRD which causes increased pathophysiological pulmonary tissue severity, increased treatment time, and increased mortality in beef calves. Calves were vaccinated with M. haemolytica in all studies as an indicator of immune response. Different dosages and forms of Co were administered to evaluate humoral immune response. Results indicate increased NRC Co concentrations affect humoral immune response and potentially improve beef calf health. Study results suggest current NRC Co concentrations should be increased to improve post-weaning health in beef calves.Item DL-methionine as a winter supplement for gestating cows grazing native range(Montana State University - Bozeman, College of Agriculture, 1988) Lodman, David WilliamItem Influence of supplementation on the productivity of ewes grazing improved pasture and suckling twins(Montana State University - Bozeman, College of Agriculture, 1988) Frey, Ana LidiaItem The effect of excess calcium with borderline and deficient phosphorus in the rations of steer calves(Montana State University - Bozeman, College of Agriculture, 1950) Lewis, James K.Item The effects of ruminally undegradable protein, propionic acid and monensin on puberty and reproductive efficiency in beef heifers(Montana State University - Bozeman, College of Agriculture, 1991) Lalman, David LeonItem Chromium-mordanted oats and 4N-HCL insoluble ash as indicators of fecal output, dry matter digestibility and dry matter intake of horses(Montana State University - Bozeman, College of Agriculture, 1993) Barbisan, David John