Faecal material

Propagated outbreaks of infection relate to the direct transmission of an infective agent from a diseased individual to a healthy, susceptible one. Mechanisms of such transmission were described in Chapter 4 and include inhalation of infective aerosols (measles, mumps, diphtheria), direct physical contact (syphilis, herpes virus) and, where sanitation standards are poor, through the introduction of infected faecal material into drinking water (cholera, typhoid). The ease oftransmission, and hence the rate of onset of an epidemic (Fig. 16.3) relates not only to the susceptibility status, and general state of health of the individuals but also to the virulence properties of the organism, the route oftransmission, the duration of the infective period associated with the disease. 

Evershed, R. P. and P. H. Bethell (1996), Application of Multi-molecular Biomarker Techniques to the Identification of Faecal Material in Archaeological Soils and Sediments, ACS Symposium Series, Vol. 625, pp. 157-172. 

Insects are considered to be another potential vector for faecal material to produce in production areas (Geldreich et al., 1964). Pollinating insects might inoculate flowers with pathogens opening the pathway for fruits to internalize pathogens and eliminating their accessibility to surface decontamination (De Roever, 1999). 

Stuart, V., Newell, R.C. and Lucas, M.I., 1982 b. Conversion of kelp debris and faecal material from the mussel Aulacomya ater by marine organisms. Mar. Ecol. Prog. Ser., 7 47-57. 

Periplanone-A and periplanone-B have been found to occur in a ratio of 1 10 in faecal material of Periplaneta americana, but only periplanone-B has been found in intestinal tracts. This could suggest that periplanone-B is a genuine sex pheromone, whereas periplanone-A could be a biologically active transformation product, which in turn can isomerize into a more stable but inactive compound. We have given hypothetical schemes for such a transformation elsewhere (32,40). 

Q2 Constipation is a condition in which faecal material moves too slowly through the large intestine. As a result too much water is reabsorbed hard, dry faeces which are difficult to move and very abrasive are produced. Infrequent or difficult defecation is a common problem in the elderly as ageing is associated with a decline in both secretory activity and motility in the gut. Constipation could develop because of emotional problems, inactive or sedentary lifestyle, lack of fibre and fluid in the diet, intestinal muscle weakness, a neurogenic disorder or an iatrogenic effect. Iatrogenic conditions are those caused by drugs or other medical treatments. 

Constipation is associated with slow transit of faecal material through the large intestine and increased fluid absorption, resulting in hard, dry faeces. 

The gastrocolic reflex stimulates motility in the colon during or just after eating, when chyme enters the colon from the ileum. The content of the distal colon may be stored there for variable periods until defecation occurs, which may be 24 hours or more after eating. The rectum is normally empty and movement of faecal material into the sigmoid colon and rectum stimulates the defecation reflex. 

Twiss P, Watling RJ, Delev D. 1994. Determination of thorium and uranium in faecal material from occupationally-exposed workers using ICP-MS. Atomic Spectroscopy 15(l) 36-39. 

Docusate sodium is an anionic surfactant that lowers the surface tension of the intestinal contents, allowing fluid and fat to penetrate, emulsify and soften faecal material for easier elimination. Evacuation is achieved without straining. It is also thought to be a stimulant similar to the anthraquinones. A laxative effect usually occurs within 1-3 days. 

Live and dead lice (about 3 mm long and greyish-white or brown in colour) and yellowish cast exoskeleton shells can be seen by combing the hair with a fine-tooth comb over a sheet of white paper, after shampooing and towelling dry. Lice faecal material (black specks) may be found on pillows and collars. 

Bethell, P.H., L.J. Goad, R.P. Evershed, and J. Ottaway. 1994. The study of molecular markers of human activity the use of coprostanol in the soil as an indicator of human faecal material. Journal of Archaeological Science 21 619-632. 

Lee, S.Y. (1997) Potential trophic importance of the faecal material of the mangrove sesarmine crab Sesarma messa. Marine Ecology Progress Series, 159, 274-283. 

Streptococcus. The streptococci are another important group whose presence is frequently associated with problems. They are commonly found in the throat, a number of dairy products, and also in water supplies contaminated with sewage or faecal material (see later). 

We have used data from experimental works carried out with tried and tested methodologies. In fish studies, the collection of faeces is an important issue as the leaching of faecal material may lead to an overestimation of the digestibility. Currently, only two reliable methods exist to collect fish faeces. The first one is based on rapid decantation (Cho and Slinger, 1978) while the second, developed by INRA, is more effective since it allows the continuous collection of faeces (Choubert et al., 1982). The INRA system is illustrated in the figure below. 

Ernst 1977). Polar metabolites in faecal material as a percent of total DCBP = 11% (Ernst et al. 1977). Therefore percent of metabolites presumed lost in faeces = 21 X 0.72 = 15%. 

The symptoms of vitamin K deficiency in chicks are anaemia and a delayed clotting time of the blood birds are easily injured and may bleed to death. It is doubtful whether, in birds, microbially synthesised vitamin K is available by direct absorption from the digestive tract, because the site of its formation is too distal to permit absorption of adequate amounts except by ingestion of faecal material (coprophagy). 

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