|Nisbet, David - Dave|
Submitted to: Foodborne Pathogens and Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/4/2008
Publication Date: 10/14/2008
Publication URL: http://hdl.handle.net/10113/21724
Citation: Krueger, N.A., Anderson, R.C., Krueger, W.K., Horne, W.J., Callaway, T.R., Edrington, T.S., Harvey, R.B., Nisbet, D.J., Cartsens, G.E., Wesley, I.V. 2008. Prevalence and concentration of Campylobacter in rumen contents and feces in pasture and feedlot-fed cattle. Foodborne Pathogens and Disease. 5:571-577. Interpretive Summary: Campylobacter is an important disease-causing bacterium responsible for more than one million cases of food poisoning in the United States each year. This bacterium is known to be able to live in the gut of animals and cattle producers are interested in finding ways to get rid of this bacterium from their cattle. In the current experiment, we looked to see if this bacterium was more often found in dairy rather than beef cattle but found that the bacterium was equally found in both types of cattle. We also looked to see where in the cattle gut the bacterium most often resides and found that the bacterium is more often found in higher numbers at the end of the digestive tract than at the beginning and that the animals diet may affect the bacterium’s ability to live in the cow’s gut. This research will help us to understand how Campylobacter can survive in the gut of cattle and to develop better approaches and strategies to get rid of this disease causing bacterium. Ultimately, this research will help farmers and food processors produce more wholesome products for the American consumer.
Technical Abstract: Campylobacter is currently one of the leading foodborne pathogens that are known to colonize the gastrointestinal tract of cattle. The incidence of Campylobacter spp. in cattle has been reported to be seasonal, to vary among age groups, and type (beef versus dairy). However, less is known about other factors that could influence the intestinal prevalence, colonization site and shedding of Campylobacter in the bovine carrier. The objective of this study was to evaluate the prevalence and concentration of Campylobacter at two sites along the digestive tract of beef and dairy type cattle consuming grass or feedlot diets. In an initial study, Campylobacter was not recovered from rumen samples of any of 10 ruminally-cannulated (6 dairy and 4 beef type) pasture-reared cattle and there was no difference (P > 0.05) between cattle types on fecal Campylobacter colonization, with 25% of each type yielding culture-positive feces (mean ± SE, 0.59 ± 0.21 Selog10 CFU/g feces). In a follow up study, ruminal and fecal samples were collected from one feedlot and one pasture based operation (n = 18 for each) in central Texas. Of the cattle on pasture, 78% of the rumen and 94% of the fecal samples were positive for Campylobacter while 50% of the rumen and 72% of the fecal samples were positive in concentrate fed animals. Overall concentration of Campylobacter was greater (P < 0.05) in fecal than in rumen fluid samples, with the greatest concentration (P < 0.05) of Campylobacter recovered from feces of concentrate-fed cattle. Our results suggest that the rumen environment and microbial population is less favorable for the growth of Campylobacter. Additionally, concentrate diets containing added rumen non-degradable protein and ionophores may provide a more hospitable lower gastrointestinal tract for the habitation of Campylobacter spp.