Page 468 - The Veterinary Laboratory and Field Manual 3rd Edition

Common clinical problems 405

Table 10.1 Gestation periods of common domestic species. These figures are
estimates for common breeds but there can be a variation.

Species Gestation period (days) Gestation period (approx.)
Cat 58–65 9 weeks
Cow 270–290 9 months
Dog 56–70 9 weeks
Donkey 365 1 year
Goat 145–155 5 months
Horse 330–340 11 months
Pig 112–115 3–4 months
Sheep 144–151 5 months

6 Note what other livestock are kept and if any centa (for example, toxoplasmosis in sheep – see
clinical disease is apparent (now and previ- Figure 3.33). At what stage of development is
ously) in these animals? the foetus? If the abortion occurred late in the
7 Are there previous offspring from the affected pregnancy, that is, near to full term, it is good to
animals? ask the following questions.

The normal gestation periods of some common 1 Did the neonate walk, that is, check hoof tips?
domestic species are given in Table 10.1. 2 Is this an abortion or a perinatal death? (The
hoof tips will be worn if the neonate has tried
to stand up.)
clinical examination of dam and sire 3 Did the neonate start breathing? (Examination
(if natural service) of the lungs will indicate whether or not the
neonate took a breath, that is, the lung tissue
After performing a full clinical examination of
the dam and sire (see Chapter 1) collect a semen will float is it contains air.)
sample and preputial wash from the bull to check 4 Did the neonate suckle? (Examination of the
for the presence of Trichomoniasis (Trichomonas stomach will indicate if the neonate took any
sp.) and other microorganisms. Examine vaginal milk, is it empty?)
smears from the dam and, if possible, also exam-
ine samples collected from the vagina of other
cows serviced by the same bull. Laboratory samples
1 Take as many of the following samples as pos-
Examination of the placenta and foetus sible:

When attending a case of abortion use the • placenta (fresh and fixed)
appropriate PPE. Examine the placenta and foe- • foetal stomach contents
tus carefully and describe any unusual features, • liver, spleen, kidneys, heart blood (fresh
for example, strange colour, smell, texture. Some and fixed) from the foetus: check if the
diseases cause characteristic changes to the pla- lung tissue floats in water.

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