Oorsig/Review
the yearly booster vaccinations is the best long-
term investment in the development of disease
resistance in the whole herd. The vaccinations
required on a specific farm should be discussed
with the local veterinarian. Weigh heifers at
weaning, 12, 18, 24 months of age and again at
the start of their breeding season. Ensure that
growth is maintained and nutrition adjusted so
that the heifers can reach 70% -75% of their
expected mature weight (critical mating weight)
at the beginning of the first limited breeding
season.
One and a half times the number of heifers that
will be required for replacement heifers are
selected. The goal of the selection is to select a
uniform group of heifers that are functionally
efficient. These heifers are retained as a separate
management group to the end of their second
breeding season. This is done according to a
3-year management plan that is worked out for
the individual group and stretches from weaning
until they are diagnosed as pregnant for the
second time by the veterinarian. ( Table 1 is an
example of such a 3-year management plan).
Replacement heifers should receive their first
series of vaccinations, before weaning but if this
was not done, they should be vaccinated against
all kinds of Clostridia (black quarter, botulism,
anthrax) and where appropriate, against red
water and tick-borne gallsickness. Vaccination
against seasonal viral diseases must also be done
in heifers. This annual vaccination followed by
12
When heifers are weighed at 24 months the vet
can also do an evaluation of their reproductive
systems by rectal examinations. Cull heifers that
did not reach the minimum breeding weight and
the heifers with an underdeveloped reproductive
system. This income will pay for the examination
and supplements that will be needed for the rest
of the group.
Deworm heifers at the end of the pasture growing
season (see Management Plan) and in the two-
month building phase before the start of the
limited breeding season. Provide supplementary
feeding in the form of a lick to the heifers.
Supplementation should be continued until 30
days after the limited breeding season. Vaccinate
heifers before the beginning of the breeding
season against diseases (such as BVD, IBR and
Vibrio) which can cause poor conception and
abortions.