Submitted to: American Society of Animal Science Southern Section Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 10/15/2002
Publication Date: 2/3/2003
Citation: LOOPER, M.L., AIKEN, G.E., EDRINGTON, T.S., ROSENKRANS JR, C.F., ELDER, R.O. 2003. INCIDENCE OF FECAL SHEDDING OF ESCHERICHIA COLI AND SALMONELLA SPP. IN BEEF CATTLE GRAZING ENDOPHYTE-INFECTED AND NON-INFECTED TALL FESCUE. AMERICAN SOCIETY OF ANIMAL SCIENCE SOUTHERN SECTION MEETING. 81(Suppl. 2):23. Interpretive Summary:
Technical Abstract: Fecal samples were obtained in replicate from mature Angus x Hereford cows (n = 49) and spring-born calves (n = 45) to determine: 1) influence of grazing endophyte-infected (E+) tall fescue (Festuca arundinacea) or non-infected (E-) tall fescue during the summer on shedding of Escherichia coli O157:H7 (EHEC) and Salmonella spp. (SM), 2) relationship of shedding EHEC and SM between cow and calf, and 3) influence of calf sex and steroid implant on bacteria shedding. Fecal samples were collected at 0700 on each collection date (August 5th and 26th). One-half of the calves were treated with a steroid implant at 60 d prior to fecal collection. Body temperature was measured from cattle at time of collection. Overall, incidence of EHEC shedding averaged 8.4 and 7.6% for calves and cows, respectively. Salmonella spp. shedding was 4.8 and 0% for calves and cows, respectively. Cows grazing E+ fescue shed less (P < 0.05) EHEC than cows grazing E- (1.8% vs 17% for E+ and E- cows, respectively). Likewise, EHEC shedding tended (P = 0.11) to be reduced in E+ calves (4.3%) compared with E- calves (13.9%). In calves, type of fescue grazed did not influence (P > 0.10) the incidence of SM shedding. Cow shedding of either EHEC or SM did not influence (P > 0.10) calf shedding of bacteria. Cow and calf body temperature did not influence (P > 0.10) shedding of EHEC or SM. Shedding of EHEC and SM in calves was not influenced (P > 0.10) by sex of calf or implant status. In this study, mature cows grazing either E+ or E- tall fescue did not shed Salmonella. Shedding of E. coli O157:H7 tended to be reduced in calves and was decreased in cows grazing endophyte-infected tall fescue.