Search

Your search keyword '"Loy, John Dustin"' showing total 161 results
Start Over Author "Loy, John Dustin"
161 results on '"Loy, John Dustin"'

9. Tulathromycin metaphylaxis increases nasopharyngeal isolation of multidrug resistant Mannheimia haemolytica in stocker heifers

Author

Crosby, William B., primary, Karisch, Brandi B., additional, Hiott, Lari M., additional, Pinnell, Lee J., additional, Pittman, Alexandra, additional, Frye, Jonathan G., additional, Jackson, Charlene R., additional, Loy, John Dustin, additional, Epperson, William B., additional, Blanton, John, additional, Capik, Sarah F., additional, Morley, Paul S., additional, and Woolums, Amelia R., additional

Published
2023
Full Text
View/download PDF

26. Laboratory Diagnosis

Author

McVey, D. Scott, primary, Brodersen, Bruce, additional, Loy, Duan, additional, and Loy, John Dustin, additional

Published
2022
Full Text
View/download PDF

28. Association of IS Vsa3 with Multidrug Resistance in Salmonella enterica Isolates from Cattle (Bos taurus).

Author

Lewis, Gentry L., Fenton, Robert J., Moriyama, Etsuko N., Loy, John Dustin, and Moxley, Rodney A.

Subjects
SALMONELLA enterica, CATTLE, MULTIDRUG resistance, MOBILE genetic elements, SALMONELLA diseases, NUCLEOTIDE sequencing
Abstract

Salmonella enterica is, globally, an important cause of human illness with beef being a significant attributable source. In the human patient, systemic Salmonella infection requires antibiotic therapy, and when strains are multidrug resistant (MDR), no effective treatment may be available. MDR in bacteria is often associated with the presence of mobile genetic elements (MGE) that mediate horizontal spread of antimicrobial resistance (AMR) genes. In this study, we sought to determine the potential relationship of MDR in bovine Salmonella isolates with MGE. The present study involved 111 bovine Salmonella isolates obtained collectively from specimens derived from healthy cattle or their environments at Midwestern U.S. feedyards (2000–2001, n = 19), or specimens from sick cattle submitted to the Nebraska Veterinary Diagnostic Center (2010–2020, n = 92). Phenotypically, 33/111 isolates (29.7%) were MDR (resistant to ≥3 drug classes). Based on whole-genome sequencing (WGS; n = 41) and PCR (n = 111), a MDR phenotype was strongly associated (OR = 186; p < 0.0001) with carriage of ISVsa3, an IS91-like Family transposase. In all 41 isolates analyzed by WGS ((31 MDR and 10 non-MDR (resistant to 0–2 antibiotic classes)), MDR genes were associated with carriage of ISVsa3, most often on an IncC type plasmid carrying blaCMY-2. The typical arrangement was floR, tet(A), aph(6)-Id, aph(3″)-Ib, and sul2 flanked by ISVsa3. These results suggest that AMR genes in MDR S. enterica isolates of cattle are frequently associated with ISVsa3 and carried on IncC plasmids. Further research is needed to better understand the role of ISVsa3 in dissemination of MDR Salmonella strains. [ABSTRACT FROM AUTHOR]

Published
2023
Full Text
View/download PDF

30. Comparison of sampling and diagnostic techniques for recovery of Mannheimia haemolytica and respiratory microbiome characterization from feedlot cattle

Author

Crosby, William Byrn, primary, Pinnell, Lee J., additional, Richeson, John T., additional, Wolfe, Cory, additional, Castle, Jake, additional, Loy, John Dustin, additional, Gow, Sheryl P., additional, Seo, Keun Seok, additional, Capik, Sarah F., additional, Woolums, Amelia R., additional, and Morley, Paul S., additional

Published
2022
Full Text
View/download PDF

42. Additional file 5 of Longitudinal assessment of the bovine ocular bacterial community dynamics in calves

Author

Bartenslager, Alison C., Nirosh D. Althuge, Loy, John Dustin, Hille, Matthew M., Spangler, Matthew L., and Fernando, Samodha C.

Subjects
parasitic diseases
Abstract

Additional file 5: Figure S5. Distribution of opportunistic pathogens Moraxella spp. and Mycoplasma spp. across the 4 sampling time points. Moraxella spp. and Mycoplasma spp. are considered as opportunistic pathogens that predispose animals to IBK infection.

Published
2021
Full Text
View/download PDF

44. Additional file 8 of Longitudinal assessment of the bovine ocular bacterial community dynamics in calves

Author

Bartenslager, Alison C., Nirosh D. Althuge, Loy, John Dustin, Hille, Matthew M., Spangler, Matthew L., and Fernando, Samodha C.

Subjects
respiratory system, human activities
Abstract

Additional file 8: Figure S8. Observed ASVs (A) and Chao1 estimates (B) indicating alpha-diversity differences between sampling time points. Significant differences in predicted functional gene alpha-diversity was identified between all sampling periods. After initial swabbing for baseline community, the diversity significantly decreased and recovered over time in subsequent samplings. The initial swabbing, would be deemed as the first perturbation or disruption to the ocular microbiota.

Published
2021
Full Text
View/download PDF

45. Additional file 3 of Longitudinal assessment of the bovine ocular bacterial community dynamics in calves

Author

Bartenslager, Alison C., Nirosh D. Althuge, Loy, John Dustin, Hille, Matthew M., Spangler, Matthew L., and Fernando, Samodha C.

Subjects
animal structures, embryonic structures
Abstract

Additional file 3: Figure S3. Distribution of “Core” ASVs across sampling time-points demonstrating predominance of opportunistic pathogens in the bovine ocular microbiota. Perturbations, or disruptions, to the ocular microbiota occurred by taking ocular swabs. Core bacterial ASVs were identified based on the presence of an ASV in at least 80% of all samples. Only 3 core ASVs were identified that fell into this criteria. The core ASVs include; Pasteurellaceae spp. (Blue), Mycoplasma spp. (Orange) and Weeksellacea spp. (Grey).

Published
2021
Full Text
View/download PDF

46. Additional file 7 of Longitudinal assessment of the bovine ocular bacterial community dynamics in calves

Author

Bartenslager, Alison C., Nirosh D. Althuge, Loy, John Dustin, Hille, Matthew M., Spangler, Matthew L., and Fernando, Samodha C.

Abstract

Additional file 7: Figure S7. Prevalence of Moraxella spp. in total (7a), as well as individually for Moraxella bovis (7b) and Moraxella bovoculi (7c) obtained from the eyes of calves at different time points. Letters denote statistically different groups (p

Published
2021
Full Text
View/download PDF

47. Additional file 9 of Longitudinal assessment of the bovine ocular bacterial community dynamics in calves

Author

Bartenslager, Alison C., Nirosh D. Althuge, Loy, John Dustin, Hille, Matthew M., Spangler, Matthew L., and Fernando, Samodha C.

Abstract

Additional file 9: Figure S9. Principal Coordinate analysis (PCoA) demonstrating between sample variations in predicted functional genes. PCoA plot was generated using a Bray-Curtis distance matrix. Day 0 and day 139 demonstrated similar gene structure that was different from 21 days and 41 days. Color scheme; Red – time point 1, Green - time point 2, Teal – time point 3, and Purple – time point 4.

Published
2021
Full Text
View/download PDF

48. Additional file 2 of Longitudinal assessment of the bovine ocular bacterial community dynamics in calves

Author

Bartenslager, Alison C., Nirosh D. Althuge, Loy, John Dustin, Hille, Matthew M., Spangler, Matthew L., and Fernando, Samodha C.

Abstract

Additional file 2: Figure S2. Principal Coordinate analysis (PCoA) demonstrating between individual cohort sample variations in beta-diversity. PCoA plot was generated using a weighted UniFrac distance matrix. A) Cohort A B) Cohort B and C) Cohort C. PERMANOVA revealed there was no significant difference between the eyes sampled at day 17 (p = 0.37, p = 0.245, and p = 0.659; respectively).

Published
2021
Full Text
View/download PDF

49. Longitudinal assessment of the bovine ocular bacterial community dynamics in calves

Author

Bartenslager, Alison, Aluthge, Nirosh D., Loy, John Dustin, Bartenslager, Alison, Aluthge, Nirosh D., and Loy, John Dustin

Abstract

Background: Infectious Bovine Keratoconjunctivitis (IBK), commonly known as pinkeye, is one of the most significant diseases of beef cattle. As such, IBK costs the US beef industry at least 150 million annually. However, strategies to prevent IBK are limited, with most cases resulting in treatment with antibiotics once the disease has developed. Longitudinal studies evaluating establishment of the ocular microbiota may identify critical risk periods for IBK outbreaks or changes in the microbiota that may predispose animals to IBK. Results: In an attempt to characterize the establishment and colonization patterns of the bovine ocular microbiota, we conducted a longitudinal study consisting of 227 calves and evaluated the microbiota composition over time using amplicon sequence variants (ASVs) based on 16S rRNA sequencing data and culture-based approaches. Beef calves on trial consisted of both male (intact) and females. Breeds were composed of purebred Angus and composites with varying percentages of Simmental, Angus, and Red Angus breeds. Average age at the start of the trial was 65 days ±15.02 and all calves remained nursing on their dam until weaning (day 139 of the study). The trial consisted of 139 days with four sampling time points on day 0, 21, 41, and 139. The experimental population received three different vaccination treatments (autogenous, commercial (both inactivated bacteria), and adjuvant placebo), to assess the effectiveness of different vaccines for IBK prevention. A significant change in bacterial community composition was observed across time periods sampled compared to the baseline (p < 0.001). However, no treatment effect of vaccine was detected within the ocular bacterial community. The bacterial community composition with the greatest time span between sampling time periods (98d span) was most similar to the baseline sample collected, suggesting re-establishment of the ocular microbiota to baseline levels over time after perturbation. The effe

Published
2021

Catalog

Books, media, physical & digital resources
See catalog results