**3.1.3** *Salmonella* **from bison**

The prevalence of *Salmonella* in the bison feces was 15% (3/20). The *Salmonella* isolates belonged to the serotypes *Salmonella* Typhimurium (Copenhagen) and *Salmonella* Worthington. In a panel of 20 antimicrobials, *Salmonella* Typhimurium (Copenhagen) was resistant to 13 of 20 antimicrobials (65% resistance), including macrolides (erythromycin, tilmicosin, tylosin), tetracyclines (chlortetracycline, oxytetracycline), chloramphenicol

Antimicrobial Drug Resistance and Molecular Characterization

**3.2** *Salmonella* **from meats** 

meats compared to 45% from raw ones.

were recovered from chicken.

Newport for TMAOs,

Syrsis, *S.* Tripoli, *S.* Uppsala, and *S.* Weltevereden.

of *Salmonella* Isolated from Domestic Animals, Humans and Meat Products 227

In the Khaitsa et al (2007b) study, 2.4% (23/959) of the samples were contaminated with *Salmonella*; with 5% (16/329), and 1% (7/607) of the raw and ready to eat meat samples testing positive for *Salmonella*, respectively. There was a significant difference in recovery of *Salmonella* (*P* < 0.05), between meat type (raw vs RTE; OR =4.2, 95% CI = 1.6, 10.8); and sampling time (OR = 0.4, 95% CI = 0.2, 0.7). Retail store and product brand did not affect *Salmonella* recovery. The twenty three *Salmonella* isolates recovered from meat products were confirmed to belong to 6 different serotypes; the predominant one being *S. hadar* followed by *S. Heidelberg, S.* typhimurium var Copenhagen, *S. newport*, *S. saintpaul* and *S. agona.*  Overall, *Salmonella* isolates from raw turkey products exhibited a higher antimicrobial resistance rate (53%) compared to those from RTE products (33%). Multidrug resistance was exhibited by 54% of the *Salmonella* isolates with the majority (62%) originating from RTE

In the Kegode et al (2008) study the distribution of samples that tested positive for *Salmonella* by meat type and meat part is summarized in Table 6. *Salmonella* was recovered from turkey breast (1/8, 13%), ground turkey breast (1/15, 7%), and turkey drumsticks (1/20, 5%) (Table 6). For chicken products *Salmonella* (2/5, 40%) were recovered from whole chicken. Thirteen *Salmonella* isolates recovered from the meat samples were confirmed by NVSL to belong to eight different *Salmonella enterica* serotypes (Table 7). The predominant serotype was *S*. *enterica s*erotype Heidelberg recovered from turkey from which *S.* Typhimurium, *S.* Newport, *S.* Saintpaul and *S.* Senftenberg were also recovered. *S*. Kentucky, *S.* Typhimurium var Copenhagen, *S.* Blockley, and one undetermined serotype

In the study by Tumuhairwe et al, 2007) that investigated the temporal and spatial distribution of 1465 salmonellosis outbreaks involving 49/50 states in the US, turkey meat associated outbreaks (TMAOs) were reported by 24 states, mostly from California and New York. Additionally, turkey meat was implicated in 4.2% of outbreaks, sea-foods (5.8%), pasta (8.3%), milk-products (8.6%), chicken (13.4%), red-meats (15.4%), eggs (21.3%), and freshproduces (22.9%). Most outbreaks were at restaurants and private-homes for TMAOs (23.2% and 21%). The major serotypes were: S. Enteritidis, S. Heidelberg, S. Reading and S.

In the study by Tumuhairwe et al (2008), there were 45 different serotypes that were recovered from 71.8% (277/386) of the salmonellosis cases in North Dakota (2000 to 2005). The four major ones contributing over 70% of the cases were: *S.* Typhimurium (93, 33.1%), *S.*  Enteritidis (40, 14.2%), *S.* Heidelberg (33, 11.7%) and *S.* Newport (32, 11.4%). The rest of the serotypes were: *S.* Saintpaul and *S.* Montevideo from eight cases each, *S.* Thompson was recovered from five cases, *S.* Hadar from four cases, *S.* Stanley*, S.* Poona*, S.* Mbandaka, *S.*  Javiana, *S.* Braenderup, and *S.* Bredeney from three patients each. *S.* Reading, *S.*  Oranienburg, *S.* Hillington, *S.* Derby, *S.* Urbana, and *S.* Albany were each recovered from 2 cases. One case each was diagnosed with *S.* Agona, *S.* Berta, *S.* Bleadon, *S.* Blockley, *S.*  Chameleon, *S.* Ealing, *S.* Edinburgh, *S.* Havana, *S.* Ibadan, *S.* Indiana, *S.* Infantis, *S.* Istanbul, *S.* Lexington, *S.* Litchfield, *S.* Manhattan, *S.* Marina, *S.* Miami, *S.* Mississippi, *S.* Muenchen, *S.* Newport, *S.* Othmarschen, *S.* Sandiego, *S.* Schwarzengrund, *S.* Senftenberg, *S.* Sepsis, *S.* 

analog – florfenicol, most sulphonamides, and penicillin, and susceptible to 7 antimicrobials including the cephalosporin – ceftiofur, the quinolone – enrofloxacin some aminoglycosides, and ampicillin (Table 5). *Salmonella* Worthington was resistant to 14 of 20 antimicrobials (70% resistance), including macrolides (erythromycin, tilmicosin, tylosin), tetracyclines (chlortetracycline, oxytetracycline), chloramphenicol analog – florfenicol, some sulphonamides, and penicillins (penicillin and ampicillin), and susceptible to 6 antimicrobials including the cephalosporin – ceftiofur, the quinolone - enrofloxacin and some aminoglycosides (Table 5). Except for ampicillin, both *Salmonella* isolates were resistant to similar antimicrobials (Table 5). None of the *Salmonella* isolates were resistant to clinically important antimicrobials.


R = Resistant S = Susceptible I-Intermediate

Table 5. Antibiotic sensitivity and resistance of *Salmonella* isolates from a bison herd
