Clinical Examination of Farm Animals - CYF MEDICAL DISTRIBUTION

CHAPTER 10
Clinical Examination of the Female
Genital System
Introduction
Examination and assessment of the genital system is
an important part of the veterinary management of
dairy cows. The target on many dairy farms is for
cows to achieve a calving to calving interval of 365
days. To achieve this target the reproductive performance
of the cow has to be closely managed. Some
consider this calving interval to be an unattainable
and possibly undesirable goal in high yielding cows.
On many farms it is only achieved by close monitoring
of the cows’ reproductive performance and
intervention with strategic hormone therapy. An assessment
of herd fertility should involve examination
of animals, including any problem animals, as
they are presented for routine fertility checks. It
should also involve consideration of the farm husbandry
and management. Information required
should include the overall disease profile of the farm,
milk yields and both past and present fertility
records.
The cow has an average gestation length of 283
days. To achieve a calving interval of 365 days she
must conceive again within 82 days (365 - 283 = 82) of
her previous calving. Uterine involution is normally
complete and resumption of overt ovarian activity
has normally commenced by 40 days after calving.
Conception should ideally occur in the period of
40 to 82 days after calving.
Beef cows are subject to less intense pressures because
their milk production has to be sufficient only
for their own calf. None the less, a calving interval of
365 days is very important to enable the herd to calve
at approximately the same time and over a short
period each year. A short calving period enables the
herd and their calves to be fed and managed as a
group. Monitoring of the reproductive performance
is also important in beef cattle.
Much routine fertility work consists of specific and
often limited examinations of the cow’s genital system.
A more detailed and comprehensive examination
may be requested and is necessary when a
particularly valuable cow fails to conceive. In every
case it must be remembered that the genital system is
just one part of the patient. Unless the patient is in
good health and her genital system is functioning
normally, conception may not occur. Whenever the
genital system is examined the veterinarian should
also assess the general health of the patient and be
alert to the possibility that disease involving other
body systems may also be present.
Applied anatomy
The anatomy of the female genital system is illustrated
in Fig. 10.1. Details of the anatomy of the
individual genital organs are given under clinical examination
below.
Signalment of the case
The age of the patient is very important. Maiden
heifers have never bred and a small proportion may
prove unable to do so. Some may be freemartins
being the twin to a male calf and having the genital
tract of an intersex. Other congenital defects resulting
in infertility are rare but none the less must be
considered in such a group of animals. Fertility problems
tend to increase with the cow’s parity because
the risk of acquired abnormalities increases with the
birth of each calf. Maiden heifers have not yet sustained
injuries at calving or experienced problems
associated with a retained placenta. These problems
are more frequent in older cows. Such animals are
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