| dc.creator |
Medardus, J. J. |
|
| dc.creator |
Molla, B. Z. |
|
| dc.creator |
Nicol, M. |
|
| dc.creator |
Morrow, W. M. |
|
| dc.creator |
Rajala-Schultz, P. J. |
|
| dc.creator |
Kazwala, R. |
|
| dc.creator |
Gebreyes, W. A. |
|
| dc.date |
2018-06-26T15:16:06Z |
|
| dc.date |
2018-06-26T15:16:06Z |
|
| dc.date |
2014 |
|
| dc.date.accessioned |
2022-10-25T08:50:51Z |
|
| dc.date.available |
2022-10-25T08:50:51Z |
|
| dc.identifier |
0044-7897 |
|
| dc.identifier |
https://www.suaire.sua.ac.tz/handle/123456789/2450 |
|
| dc.identifier.uri |
http://hdl.handle.net/123456789/90718 |
|
| dc.description |
ASM News- American Society for Microbiology Vol. 80,2014 Number 7;p. 2317–2325 |
|
| dc.description |
The study aimed to characterize the role of heavy metal micronutrients in swine feed in emergence of heavy-metal-tolerant and multidrug-resistant Salmonella organisms. We conducted a longitudinal study in 36 swine barns over a 2-year period. The feed and fecal levels of Cu2+ and Zn2+ were measured. Salmonella was isolated at early and late finishing. MICs of copper sulfate and zinc chloride were measured using agar dilution. Antimicrobial susceptibility was tested using the Kirby-Bauer method, and 283 isolates were serotyped. We amplified pcoA and czcD genes that encode Cu2+ and Zn2+ tolerance, respectively. Of the 283 isolates, 113 (48%) showed Cu2+ tolerance at 24 mM and 164 (58%) showed Zn2+ tolerance at 8 mM. In multivariate analysis, serotype and source of isolates were significantly associated with Cu2+ tolerance (P < 0.001). Fecal isolates were more likely to be Cu2+ tolerant than those of feed origin (odds ratio [OR], 27.0; 95% confidence interval [CI], 2.8 to 250; P = 0.0042) or environmental origin (OR, 5.8), implying the significance of gastrointestinal selective pressure. Salmonella enterica serotypes Typhimurium and Heidelberg, highly significant for public health, had higher odds of having >20 mM MICs of Cu2+ than did “other” serotypes. More than 60% of Salmonella isolates with resistance type (R-type) AmStTeKm (32 of 53) carried pcoA; only 5% with R-type AmClStSuTe carried this gene. czcD gene carriage was significantly associated with a higher Zn2+ MIC (P < 0.05). The odds of having a high Zn2+ MIC (≥8 mM) were 14.66 times higher in isolates with R-type AmClStSuTe than in those with R-type AmStTeKm (P < 0.05). The findings demonstrate strong association between heavy metal tolerance and antimicrobial resistance, particularly among Salmonella serotypes important in public health. |
|
| dc.format |
application/pdf |
|
| dc.language |
en |
|
| dc.publisher |
ASM News- American Society for Microbiology |
|
| dc.subject |
Salmonella enterica serotypes |
|
| dc.subject |
Food-borne illness |
|
| dc.subject |
Multidrug-resistant |
|
| dc.subject |
Micronutrients |
|
| dc.subject |
U.S. Swine |
|
| dc.subject |
Swine Production |
|
| dc.subject |
Salmonellae |
|
| dc.title |
In-feed use of heavy metal micronutrients in U.S. Swine production systems and its role in persistence of multidrug-resistant Salmonellae |
|
| dc.type |
Article |
|