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Item Experimental infection of specific pathogen-free domestic lambs with Mycoplasma ovipneumoniae(Montana State University - Bozeman, College of Agriculture, 2021) Johnson, Thea Haviland; Chairperson, Graduate Committee: Diane Bimczok; Diane Bimczok, Kerri Jones, Cassie Mosdal, Steven Jones, SK, CB, AS, and B. Tegner Jacobson were co-authors of the article, 'Immunoglobulin transfer, survival, and growth in motherless lambs fed a bovine serum-based colostrum replacer' which is contained within this thesis.; Kerri Jones, B. Tegner Jacobson, Julia Schearer, Noah Adams, Isaak Thornton, Cassie Mosdal, Steven Jones, Mark Jutila, Agnieszka Rynda-Apple, Thomas Besser and Diane Bimczok were co-authors of the article, 'Experimental infection of specific-pathogen-free domestic lambs with Mycoplasma ovipneumoniae causes asymptomatic colonization of the upper airways that is resistant to antibiotic treatment' in the journal 'Veterinary microbiology' which is contained within this thesis.Mycoplasma ovipneumoniae (M. ovi) is a respiratory pathogen commonly found in sheep and goats. It is associated with mild to moderate respiratory disease in domestic lambs, but severe pneumonia outbreaks in wild ruminants, specifically bighorn sheep. The goal of our study was to better understand the role of M. ovi as a respiratory pathogen in domestic sheep and to explore potential antibiotic treatment approaches. We first established a flock of specific pathogen-free (SPF) lambs through supervised lambing and motherless rearing in a Large Animal BSL-2 facility. Lambs were fed a colostrum replacer that yielded low mortality, steady weight gain and serum IgG and protein concentrations comparable to those of lambs raised on ewe colostrum. We inoculated the SPF lambs with field isolates of M. ovi and monitored the lambs for eight weeks for colonization with the bacteria, M. ovi-specific antibodies, clinical symptoms, and cellular and molecular correlates of lung inflammation. After eight weeks, lambs were treated with the macrolide antibiotic gamithromycin and observed for an additional four weeks. Stable colonization of the upper respiratory tract with M. ovi was established in all four M. ovi-inoculated, but in none of the four mock-infected lambs. All M. ovi-infected lambs developed a robust antibody response to M. ovi within 2 weeks. However, we did not observe significant clinical symptoms, evidence of lung damage or inflammation in any of the infected lambs. Interestingly, treatment with gamithromycin failed to reduce M. ovi colonization. These observations indicate that, in the absence of co-factors, M. ovi causes asymptomatic colonization of the upper respiratory tract of that is resistant to clearance by the host immune response as well as by gamithromycin treatment in domestic lambs.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 The effects of the bovine respiratory syncytial virus on the ciliated epithelium of fetal bovine tracheal organ culture(Montana State University - Bozeman, College of Agriculture, 1979) Cantrell, Charles GarrettItem Importance of L-selectin in the induction of immune responses in the upper respiratory tract(Montana State University - Bozeman, College of Agriculture, 2001) Csencsits, Keri LinItem Bovine respiratory syncytial (RS) virus : experimental infection in African pygmy goats(Montana State University - Bozeman, College of Agriculture, 1981) Blixt, John AndrewItem Respiratory-related quality of life among people exposed to Libby asbestos(Montana State University - Bozeman, College of Nursing, 2011) Warren, Ginger Parrish; Chairperson, Graduate Committee: Wade G. HillThe purpose of this descriptive study was to explore respiratory-related quality of life among people that have been exposed to Libby amphibole asbestos. This thesis analyzed data from a descriptive research study conducted by a team from Montana State University College of Nursing in collaboration with the Center for Asbestos-Related Diseases (CARD) clinic in Libby from September 1, 2006 through August 31, 2007. The main goal of the parent study was to examine the bio-psychosocial health status of persons exposed to Libby amphibole asbestos. This thesis augments that work by examining respiratory-related quality of life from a Libby sample and comparing with other groups reported in the scientific literature. Findings show that overall respiratory-related quality of life for persons exposed to Libby asbestos was similar to other respiratory-related disease cohorts. Implications to nursing practice and limitations of the study are discussed.