Page 471 - The Veterinary Laboratory and Field Manual 3rd Edition

408 Susan C. Cork

10.2 diarrhoea showing other signs of ill health? Is the problem
recent or chronic? Has the animal been treated
The term diarrhoea is used for soft or partially for parasites recently? Has the farm manager
formed faeces which may be passed more fre- or owner given any other medicine (includ-
quently than normal. A wide range of diseases ing traditional remedies) to the animal? Are
present with diarrhoea as one of the predomi- other livestock or people showing signs of ill
nant clinical signs. There are various forms of health?
diarrhoea with a range of severity. In severe
acute cases animals may pass very watery stools,
show signs of abdominal pain and become dehy- Perform a thorough clinical
drated quite rapidly as is seen in many systemic examination
bacterial diseases such as colisepticaemia or
salmonellosis. In these cases, there may also be Taking appropriate biosecurity measures, exam-
blood and mucus in the stool as well as undi- ine the sick animal(s) and others in the herd/
gested fibre. In other cases, diarrhoea may be village. Perform a full clinical examination and
mild, with only a slight indication of abdomi- check for any evidence of a rise in temperature,
nal discomfort observed in the animal, possibly weight loss, dehydration and so on. Examine the
a change in intestinal sounds and usually little faeces and describe the colour, smell and consis-
weight loss. Mild cases of diarrhoea may indicate tency. Is there any blood or mucus present, are
the presence of parasites or a recent change in there any strips of intestinal lining present? Is
diet. Excitement and fear may also cause loose the smell of the urine strong? What is the colour
faeces. If an animal frequently passes a large vol- of the urine? Urine will be dark if the animal is
ume of well formed, but incompletely digested dehydrated. Check the mucous membranes and
faeces, this may indicate an unsuitable diet or skin elasticity – is the animal anaemic? dehy-
it may imply incomplete digestion or malab- drated? jaundiced? Are there any haemorrhages
sorption. If prolonged, even mild diarrhoea or blisters in the mouth? Is the animal showing
may become debilitating and result in signifi- signs of abdominal pain?
cant weight loss and nutrient deficiencies. It is
important to take a good clinical history and to
perform a full clinical examination on the animal collect laboratory samples
in order to determine whether the diarrhoea is a
primary or secondary problem. Determining the If there are several animals affected or if an ani-
cause of the diarrhoea will ensure that treatment mal is very unwell, submit the following samples
options are correctly assessed. along with a full clinical history and description
of the case (use laboratory submission forms –
see Appendix 2 – for this purpose):
take a full history
1 faecal sample from affected and in-contact
It is very important to take a good clinical his- animals (5–10 g in labelled bottle or plastic
tory. Determine whether it is an isolated case bag)
or part of a wider problem. Check whether or 2 whole blood and blood smear
not there have been any recent changes in man- 3 serum from affected and ‘in-contact’ animals
agement, for example, a new diet or a recent 4 necropsy of dead animals and other samples
introduction of new stock. Has the animal been as indicated.

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