Page 467 - The Veterinary Laboratory and Field Manual 3rd Edition

404 Susan C. Cork

the bull (for example, sperm count, sperm mor- or a larger number of abortions than would be
phology and motility and so on). However, if expected in an individual herd (for example, 5%)
cows continue to return to service after AI it is this can be serious and requires a thorough and
also important to check the AI technician’s tech- detailed investigation. It should be noted that
nique and the suitability of the storage facilities, some infectious causes of abortion are zoonotic
as well as the quality of the semen. (that is, brucellosis and leptospirosis) and so
There are many causes of infertility including precautions should be taken to prevent exposure
sub-clinical disease but it is important to ini- of field staff and community members to these
tially check for faults in animal husbandry. pathogens. Routine examination of any case of
Consider the following questions. abortion requires taking a full clinical history,
examination of the affected animal(s) and the
1 Are the animals submitted for AI really in heat? aborted foetus/placenta. Other sick animals in
2 Is the technician using the correct technique? the herd should also be examined. Biosecurity
3 Check the quality of the semen, that is, send measures (that is, disinfection of hands and
a sample to the laboratory for expert evalu- footwear, appropriate use of personal protec-
ation of the morphology and motility of the tive equipment [PPE], correct disposal of waste
spermatozoa. products, change of coveralls and so on) should
4 Examine the animal(s) affected. Is a specific be taken to avoid transmitting a pathogen from
age group affected? (Some diseases are more one farm or region to another. Although the
common in younger animals.) Is the problem epidemiological pattern of the disease and the
restricted to a particular village? What is the associated clinical presentation can suggest
general health status of the herd? (Underweight the most likely cause of abortion, a confirma-
animals will often fail to come into oestrous.) tory diagnosis will depend on the submission of
5 Routine and more specific samples should suitable samples to the laboratory.
be taken from affected animals to check
for reproductive health and well as general
health status, for example, faeces, blood History
smear, whole blood, serum as well as vaginal
swabs/smears and so on. A clinical history should include the following
details and answers to the following questions.
It may be necessary to call for more specialized
veterinary assistance to complete a detailed rec- 1 The date, location, owner and animal details.
tal/vaginal examination of each ‘infertile’ cow 2 How many animals are affected and which
in order to determine the size and shape of the age group(s) are involved?
uterus and the presence of abnormalities in 3 Record recent changes in management,
the reproductive tract. breeding history (that is, AI or natural ser-
vice), and nutrition.
4 An outline of recent veterinary procedures,
abortion vaccination, worming, treatment with antibi-
otics and so on.
A number of causes of abortion can affect individ- 5 A description of any clinical signs observed in
ual animals (for example, septicaemia) and may affected animal(s) prior to abortion and esti-
not require a specific investigation. However, mate at what stage of pregnancy the abortion
if there is an outbreak of abortion in an area, occurred.

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