Survival of Indicator and Pathogenic Bacteria in Bovine Feces on Pasture

Abstract

The survival of enteric bacteria was measured in bovine feces on pasture. In each season, 11 cow pats were prepared from a mixture of fresh dairy cattle feces and sampled for up to 150 days. Four pats were analyzed for Escherichia coli, fecal streptococci, and enterococci, and four inoculated pats were analyzed for Campylobacter jejuni and Salmonella enterica. Two pats were placed on drainage collectors, and another pat was fitted with a temperature probe. In the first 1 to 3 weeks, there were increases (up to 1.5 orders of magnitude) in the counts of enterococci (in four seasons), E. coli (three seasons), fecal streptococci (three seasons), and S. enterica (two seasons), but there was no increase in the counts of C. jejuni. Thereafter, the counts decreased, giving an average ranking of the times necessary for 90% inactivation of C. jejuni (6.2 days from deposition) < fecal streptococci (35 days) < S. enterica (38 days) < E. coli (48 days) < enterococci (56 days). The pat temperature probably influenced bacterial growth, but the pattern of increases and decreases was primarily determined by desiccation; growth occurred when the water content was greater than 80%, but at a water content of 70 to 75% counts decreased. E. coli and enterococcus regrowth appeared to result from pat rehydration. Of 20 monthly leaching losses of E. coli, 16 were <10% of the total counts in the pat, and 12 were <1%. Drainage losses of C. jejuni (generally <1%) were detected for only 1 to 2 months. Although enterococci exhibited the best survival rate, higher final counts suggested that E. coli is the more practical indicator of bovine fecal pollution.

In Vitro Antagonistic Activity Evaluation of Lactic Acid Bacteria (LAB) Combined with Cellulase Enzyme Against Campylobacter jejuni Growth in Co-Culture

“…Thus, they are widely disseminated in the farm environment, and they can be concentrated in raw poultry meat. Because of its susceptibility to multiple environmental stresses (e.g., temperature, relative humidity, and air composition), it is known that Campylobacter does not grow outside its host, but is able to survive in litter [17], in sewage [1], in biofilms formed in the water distribution systems of poultry houses [12], and for more than two weeks in feces [32]. The reduction of Campylobacter contamination at different levels of the poultry production chain, especially at the primary production level, should decrease the risk of human infection.…”

Monitoring Recreational Waters: How to Integrate Environmental Determinants

“…For instance, some agents can persist in soil for many months after exiting an animal's gastrointestinal tract [51,52]. The impact of animals at pasture can vary according to animal density.…”

Estimating the probability of an extinction or major outbreak for an environmentally transmitted infectious disease

“…For these values, R 01 ≈ 5.88 and R 02 ≈ 0.51 which implies that disease transmission occurs primarily through host-to-host contact. However, it has recently been accepted that transmission of pathogens spreading through the fecal-oral route in their animal host populations occurs primarily indirectly through the contaminated environment and that the [58,65] direct host-to-host transmission is negligible [11,25,26]. Thus, we assume a smaller value (log 10 decrease) of β 1 and larger value (log 10 increase) of β 2 compared with [71,72].…”

“…Thus, there will be no more than 100 cattle in the herd in the long-run. According to Sinton et al [58], the carrying capacity of free-living Salmonella in cattle fecal debris could be as high as 6.5 × 10 7 pathogens per gram of feces. On average, cattle produce 30 kg of feces per day [65].…”

“…Some free-living pathogens are capable of long-term survival and even growth within the environment [9,45,58,73]. Moreover, infectious hosts contribute to the load of free-living pathogen in the environment through shedding.…”