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298 results on '"Williamson, J. H."'

16. Evaluating a commercial PCR assay against bacterial culture for diagnosing Streptococcus uberis and Staphylococcus aureus throughout lactation.

Author

Steele, N. M., Williamson, J. H., Thresher, R., Laven, R. A., and Hillerton, J. E.

Subjects
*POLYMERASE chain reaction, *STREPTOCOCCUS uberis, *STAPHYLOCOCCUS aureus, *LACTATION in cattle, *BACTERIAL cultures, *CATTLE, *COLOSTRUM, *THERAPEUTICS
Abstract

The performance of a commercial, real-time PCR assay was compared with traditional bacterial culture for the identification of Streptococcus uberis and Staphylococcus aureus in bovine milk collected at different stages of lactation. Initial validation tests using fresh and frozen quarter milk samples identified factors that affected the success of the PCR. Therefore, the standard protocol was adjusted for samples collected at the first milking postpartum (colostrum) and from clinical mastitis cases. The adjustment involved PCR testing both undiluted and diluted (1 in 10 with sterile water) DNA extracts. The performance comparison between culture and the PCR assay used milk samples collected aseptically from individual quarters of mixed-age spring-calving dairy cows, during early, mid, and late lactation. Bacterial culture results were used to select a subset of samples for PCR testing (n = 315) that represented quarters with a current or prior Strep. uberis or Staph. aureus infection. Compared with culture, PCR had a sensitivity of 86.8% and specificity of 87.7% for detecting Strep. uberis (kappa = 0.74) and 96.4% and 99.7%, respectively, for detecting Staph. aureus (kappa = 0.96). The dilution of DNA extracts for colostrum and clinical samples increased the relative sensitivity from 79.2% to 86.8% for Strep. uberis detection and from 92.9% to 96.4% for Staph. aureus, presumably through diluting unidentified PCR inhibitors. The sensitivity for detecting Strep. uberis using PCR, relative to culture, was similar throughout lactation (85-89%), whereas relative specificity was lowest immediately postcalving (64%) but improved in mid and late lactation (98%). Specificity estimates for samples collected in early lactation can be optimized by reducing the cutoff cycle threshold (Ct) value from the recommended value of 37 to 34. Although using this value improved specificity (77%), it reduced test sensitivity (77%). The PCR assay lacked agreement with culture in early lactation, specifically for diagnosing Strep. uberis. Thus, PCR should not be used as the only tool for diagnosing mastitis in early lactation. [ABSTRACT FROM AUTHOR]

Published
2017
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17. Peripartum infection with Streptococcus uberis but not coagulase-negative staphylococci reduced milk production in primiparous cows.

Author

Pearson, L. J., Williamson, J. H., Turner, S.-A., Lacy-Hulbert, S. J., and Hillerton, J. E.

Subjects
*STREPTOCOCCUS uberis, *CATTLE parturition, *MILK yield, *COAGULASE, *BOVINE mastitis
Abstract

The effect of an intramammary infection (IMI) at calving on the milk yield of heifers during their first 200 d in milk (DIM) was estimated by comparing monozygotic twins, where one member had a naturally occurring IMI detected at the first milking after calving and the other twin did not. Data collected weekly over a full lactation for 29 twin pairs were used to estimate the effects of a pericalving Streptococcus uberis IMI on milk yield and composition. Data for 19 twin pairs were used to estimate the effects of pericalving coagulase-negative staphylococci (CNS) IMI. A heifer with a Strep. uberis IMI produced 200 kg (7%) less milk during the first 200 d of lactation compared with her uninfected twin, with significant differences evident throughout the 200-d period. Similar milk losses were recorded for heifers that developed CM or remained subclinical. An elevated milk SCC for infected heifers was only apparent for the first month (d 2-30), although SCC tended to remain high during the second (d 31-60) and third (d 61-90) months. Milk protein concentrations were greater in the Strep. uberis-infected twin over the 200-d period, whereas fat and lactose concentrations showed little change. An IMI caused by Strep. uberis was associated with a lower milk yield, whereas an IMI by CNS was not, despite CNS-infected twins having a higher SCC than their uninfected twin for the first 30 d of lactation. [ABSTRACT FROM AUTHOR]

Published
2013
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18. Field Observations on the Variation of Streptococcus uberis Populations in a Pasture-Based Dairy Farm.

Author

Lopez-Benavides, M. G., Williamson, J. H., Pullinger, G. D., Lacy-Hulbert, S. J., Cursons, R. T., and Leigh, J. A.

Subjects
*STREPTOCOCCUS, *DAIRY farms, *PASTURES, *COWS, *DAIRY cattle, *GRAZING
Abstract

Microbiological and molecular tools were used to monitor Streptococcus uberis populations on farm tracks and paddocks on a dairy farm during different seasons of a year to identify and profile potential environmental niches of Strep. uberis in a pasture-based dairying system. Farm tracks of high or low cow traffic were sampled every 2 wk for an entire year and Strep. uberis numbers were enumerated from a selective medium. During each season of the year, paddocks were sampled for the presence of Strep. uberis before and after grazing by dairy cows. Farm tracks of high cow traffic generally had greater concentrations of Strep. uberis isolated compared with tracks with less cow traffic, but there was also significant variation in the concentrations of Strep. uberis contamination among seasons, being highest in winter and lowest in summer. The bacterium was detected in paddocks only after cow grazing had occurred, but the bacteria could still be detected in soil for up to 2 wk following grazing in winter. Multilocus sequence typing showed great heterogeneity, with some commonality between farm track and milk isolates, which may help explain cow-to-environment or environment-to-cow transmission of the bacterium in the dairy setting. [ABSTRACT FROM AUTHOR]

Published
2007
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19. Polygyra; affinis

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-081258%5DUMMZ-MOL-81224-81260, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/081258/UMMZ-MOL-81224-81260/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

Published
1920

20. Elliptio; buckleyi

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-042771%5DUMMZ-MOL-42771-42807, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/042771/UMMZ-MOL-42771-42807/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

Published
1921

21. Elliptio; jayensis

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-042770%5DUMMZ-MOL-42734-42770, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/042770/UMMZ-MOL-42734-42770/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

Published
1921

22. Felipponea; neritiniformis

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-068295%5DUMMZ-MOL-68273-68309, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/068295/UMMZ-MOL-68273-68309/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

Published
1922

23. Elliptio; ahenea

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-042769%5DUMMZ-MOL-42734-42770, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/042769/UMMZ-MOL-42734-42770/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

Published
1921

24. Villosa; vibex

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-042772%5DUMMZ-MOL-42771-42807, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/042772/UMMZ-MOL-42771-42807/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

Published
1921

25. Subulina; octona

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-147158%5DUMMZ-MOL-147117-147158, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/147158/UMMZ-MOL-147117-147158/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

26. Bostryx; laurentii

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-164253%5DUMMZ-MOL-164253, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/164253/UMMZ-MOL-164253/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

27. Bostryx; laurentii

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-164253%5DUMMZ-MOL-164244-164284, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/164253/UMMZ-MOL-164244-164284/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

28. Pomacea; glauca

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-045097%5DUMMZ-MOL-45091-45127, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/045097/UMMZ-MOL-45091-45127/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

29. Leptinaria; anomala

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-161336%5DUMMZ-MOL-161333-161373, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/161336/UMMZ-MOL-161333-161373/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

30. Thaumastus; melanocheilus

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-160889%5DUMMZ-MOL-160882-160922, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/160889/UMMZ-MOL-160882-160922/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

31. Allopeas; micra

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-242734%5DUMMZ-MOL-242713-242752, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/242734/UMMZ-MOL-242713-242752/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

32. Allopeas; micra

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-147527%5DUMMZ-MOL-147495-147536, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/147527/UMMZ-MOL-147495-147536/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

33. Bocourtia; aquila

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-164237%5DUMMZ-MOL-164237, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/164237/UMMZ-MOL-164237/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

34. Bocourtia; aquila

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-164237%5DUMMZ-MOL-164203-164243, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/164237/UMMZ-MOL-164203-164243/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

35. Beckianum; beckianum

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-242680%5DUMMZ-MOL-242673-242712, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/242680/UMMZ-MOL-242673-242712/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

36. Beckianum; beckianum

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-147434%5DUMMZ-MOL-147411-147452, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/147434/UMMZ-MOL-147411-147452/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

37. Scholvienia; tarmensis

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-146910%5DUMMZ-MOL-146907-146948, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/146910/UMMZ-MOL-146907-146948/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

38. Obeliscus; plicatellum

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-147536%5DUMMZ-MOL-147495-147536, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/147536/UMMZ-MOL-147495-147536/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

39. Habroconus; cassiquiensis

Author

Williamson, J. H., Williamson, J. H., Williamson, J. H., and Williamson, J. H.

Abstract

http://name.umdl.umich.edu/IC-MOLLUSK1IC-X-160994%5DUMMZ-MOL-160964-161004, https://quod.lib.umich.edu/cgi/i/image/api/thumb/mollusk1ic/160994/UMMZ-MOL-160964-161004/!250,250, The University of Michigan Library provides access to these materials for educational and research purposes. These materials may be under copyright. If you decide to use any of these materials, you are responsible for making your own legal assessment and securing any necessary permission. If you have questions about the collection, contact the UMMZ Mollusks Division professional staff: mollusk1ic-dlps-help@umich.edu. If you have concerns about the inclusion of an item in this collection, please contact Library Information Technology: libraryit-info@umich.edu.

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