The Effect of Flaming of Taps Before Sampling on the Bacteriological Examination of Farm Water Supplies

Abstract

Summary: The flaming of taps before sampling caused no significant differences in the most probable numbers of coli‐aerogenes organisms or Bact. coli in water samples, or in the colony counts at 37 or 22°, though there was a tendency for the bacterial content to be lowered.

Coli‐aerogenes Bacteria in Dairy Water Supplies

“…coli type I is essentially an index of recent excretal pollution since it tends to die out fairly quickly in soil and water, whereas intermediate-aerogenes-cloacae types persist longer and may even proliferate in organic deposits. As mentioned in a previous paper (Cuthbert, 1954) doubts have been raised about this and certainly the results obtained from a large number of supplies indicate that numbers of Bad. coli type I are closely associated with the total number of coli-aerogenes bacteria.…”

“…The value of the 44" test is dependent on the accuracy of the assumption that numbers are related to the extent of recent excretal contamination. The seasonal variation which has been previously noted (Cuthbert, 1954) indicates that this may not be altogether true, and certainly there are occasions when it is difficult to correlate test results with field inspections.…”

“…The nozzle was then flamed, a further 2-3 gal of water run off to cool the nozzle, and a second sample taken. The results of this work have been published by Thomas et al (1954) and the effect of the treatments on the coli-aerogenes content of the samples is shown in Table 1. Clearly, flaming caused little difference (a fact confirmed by a statistical analysis).…”

“…TWO YEARS ago in a paper to this Society (Cuthbert, 1954) an outline was given of the work being done on farm dairy water supplies by the Bacteriologists of the National Agricultural Advisory Service. Some of the data obtained and the difficulties experienced were considered.…”