Page 481 - The Veterinary Laboratory and Field Manual 3rd Edition

418 Susan C. Cork

physical or chemical disturbance but are typi- 1 Clinical history. How many animals and
cally exhibited by tremors, circling, changes in which species are affected? Which age groups
consciousness (that is, excitability, somnolence are involved? When were the clinical signs
or depression), abnormal movement and behav- first observed? Are the clinical signs progres-
iour (that is, head pressing, paresis, ataxia) and/ sive? What is the vaccination history of the
or recumbency. There are also a range of meta- animal(s)? What changes in management
bolic disorders and systemic diseases which have occurred recently (that is, diet, grazing,
may directly affect a range of organ systems but housing, water supply and so on)?
are represented by clinical signs suggestive of a 2 Clinical examination. Observe the animal(s)
neurological disorder, for example, staggering in from a distance, watch for changes in gait and
grass sickness and tremors in milk fever. Damage posture, check for changes in behaviour and
to the peripheral nervous system, for example, other signs of disease. Are there any ectopara-
trauma to the radial nerve associated with a sites present or any evidence of animal bites?
fractured humerus (front limb bone), does not Perform a routine health check (temperature,
usually affect consciousness but will result in pulse, heart rate and respiration). Check the
temporary or permanent changes to movement. faeces, urine and mucous membranes. TAKE
Pain associated with colic and other disorders APPROPRIATE PRECAUTIONS IF RABIES
may also result in abnormal behaviour therefore IS SUSPECTED.
it is important to take a good clinical history and 3 Sample collection. Take samples to assess the
to perform a thorough clinical examination to general health status of the animal (faeces,
identify the cause of the problem. In some dis- urine, blood), it may be advisable to collect
eases, or if the animal is nervous or agitated, it specific samples for diseases common to the
is important to ensure full restraint of the ani- area, for example, East coast fever (cerebral
mal, with the assistance of a competent handler, complications). In some cases, a thorough
before samples are collected. Special precautions necropsy may be required to locate brain
must be taken if rabies is suspected, that is, staff lesions and allow confirmation of a diagnosis.
should be vaccinated for rabies if exposure to
rabid animals is likely and protective cloth- Table 10.10 summarizes some causes of com-
ing should be worn when collecting samples. mon clinical signs which may be associated with
Sample collection guidelines and requirements a neurological disorder. The table is not meant
for the handling of suspect cases of rabies will to be comprehensive but aims to give some idea
be determined by the local veterinary and pub- of the range of possible causes and the common
lic health authorities. If unsure, please contact metabolic and infectious diseases that need to
your regional veterinary officer before handling be considered.
potentially infectious material.
The epidemiological pattern of the disease
under investigation can give some indication of Bibliography
the most likely cause of neurological disturbance
in a group of animals but it may be difficult to Constable, P., Hinchcliff, K W., Done , S., Gruenberg, W.
diagnose the cause of the problem in an indi- (2016) Veterinary Medicine, 11th edn. A Textbook
vidual animal unless a detailed neurological of the Diseases of Cattle, Horses, Sheep, Pigs and
Goats, 2 vols. Saunders Ltd, Philadelphia, PA.
examination is carried out. This may require the Merck Veterinary Manual (n.d.) https://www.merck
involvement of a specialist. vetmanual.com/.

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