Isolation of Escherichia coli serotype O157:H7 and other Shiga-like-toxin-producing E. coli from dairy cattle

Abstract

We examined 1,266 fecal specimens from healthy cattle during the investigations of two sporadic cases of hemolytic uremic syndrome associated with raw milk consumption and an outbreak of gastroenteritis and hemolytic uremic syndrome caused by Escherichia coli serotype 0157:117. We collected specimens from heifers, calves, and adult cows on 22 farms, in a stockyard, and in a packing house. We also collected 3 raw hamburger specimens from a restaurant and 23 raw milk samples from two farms. All specimens were examined for E. coli 0157:H7 by using sorbitol-MacConkey agar, H immobilization, 0157 agglutination, and tissue culture cytotoxicity. E. coli 0157:H7 was isolated from 16 heifers or calves and 1 adult cow on 22 farms, 1 stockyard calf, 2 beef specimens, and 1 raw milk sample. Selected fecal specimens were also examined for the presence of other Shiga-like-toxin-producing E. coli (SLTEC) by testing polymyxin B extracts of colony sweeps and then testing individual colonies for toxin production. SLTEC other than 0157 was isolated from 8 of 10 farms investigated and from the stockyard; 8% of adult cows and 19% of heifers and calves were positive for SLTEC. Several animals were positive for SLTEC by colony sweep only. This investigation demonstrates that dairy cattle are a reservoir of E. coil 0157:H7 and other SLTEC.

Seasonal variation of Shiga toxin-encoding genes (stx) and detection ofE. coliO157 in dairy cattle from Argentina

“…The prevalence in calves is not consistent with the results obtained by Cobbold and Desmarchelier (2002) who found a prevalence of 46% by using a collective breeding system and 6AE4% by single breeding system while in this study the prevalence was 43% by single breeding system. In Brazil, similar percentages were found (43%) by Moreira et al (2003), while in the USA the prevalence obtained in calves was much lower (19%) (Wells et al 1991).…”

“…In France, the prevalence obtained was similar (Fremaux et al 2006). These values were higher than those found in some countries such as the Netherlands (8AE8-22AE4%) (Heuvelink et al 1998), Australia (16AE7%) (Cobbold and Desmarchelier 2000) and the USA (8%) (Wells et al 1991). However, there are countries with higher prevalence such as Switzerland (44AE3%) (Busato et al 1999), Canada (62AE1%) (Jackson et al 1998) and Brazil (52-82%) (Leomil et al 2003;Moreira et al 2003;Vicente et al 2005).…”

High numbers of Shiga toxin-producing found in bovine faeces collected at slaughter in Japan

“…In 4 of 21 animals infected with O26:H11 and O121:H19, this high rate of carriage in the faeces was also demonstrated. In previous reports [14,41], O157:H7 was found to be more frequently carried by calves and heifers than by adult cattle, and young dairy animals can shed O157:H7 in faeces at 10 3 -10 5 CFU/g [14] while beef cattle can shed O26:H11, O111:H-and O157:H7 in faeces at 10 2 -10 9 CFU/g [7]. Thus, young animals may be principal reservoirs of group 1.…”

“…O26:H11: stx1 was isolated from 20 animals (3.3%), O111:H-: stx1 and O121:H19: stx2 from each one animal (0.2%) and O157:H7: stx1, stx2 and stx1 and 2 from 9 animals (1.5%). Recent reports stated that O26:H11 and O111:H-infection rates in cows of dairy farms were 0 to 1.7% in Australia [39], Germany [40] and the United States [41] but 0.6-2.5% in Japan [6]. Rates in calves of beef farms were 7.3-19.2% in Japan [13], respectively.…”

Grazing Management Effects on Sediment, Phosphorus, and Pathogen Loading of Streams in Cool-Season Grass Pastures

“…Cattle may shed fecal pathogens such as BCV, BRV, and E. coli O157:H7 (Crouch and Acres, 1984;Wells et al, 1991;Lucchelli et al, 1992). Shedding of pathogens in the present study was rare, occurring only once during the study, when BCV was shed by one cow.…”