Beef cattle production and management
Practical Action
Chapter Three - Reproduction in beef cattle
Introduction
Most communal farmers run bulls with the cows throughout the year, claiming that higher calving
rates can be obtained and that bull requirements are reduced. This is however, not desirable
since controlled breeding can be practiced resulting in restricted calving season - even more -
batches of animals produced and routine management practices become easy.
Objectives:
At the end of this chapter participants should be able to:
Understand bull selection methods and management practices
Understand heifer selection and management practices
Detect different signs of heat in cows and heifers
Appreciate principles of calving, calf rearing and management
Tools:
Pictures, markers, flip charts, rulers, strings, one bull, one cow, two calves, two weaner plates
and two bottles.
Method:
Brainstorm, demonstrations and discussions.
Duration:
2 hours.
Brainstorm
Ask the participants to list various bull and heifer selection methods they use in the Zambezi
Valley and signs of heat in cows and heifers. Write down their responses on the flip chart.
Demonstrations
a) Carry out a breeding soundness evaluation exercise as illustrated in this section.
b) Carry out colostrums feeding and weaner plate application demonstrations as illustrated in
this section.
Practical
a) Take the group to the available herd of cattle and let them practice in groups as
demonstrated.
Breeding season management
The breeding season should be as short as possible without reducing calving percentages. The
length of the breeding season for heifers should be approximately nine weeks. For maximum
profitability, the breeding season should be adjusted so as to make optimum use of the cheapest
source of the summer grazing.
The table below illustrates the appropriate breeding and calving seasons:
Region
Bulling Season
Bulling Season
High veld
Low veld
Nov 15 – Feb 13
Dec 15 – Mar 16
Sept – Oct – Nov
Oct – Nov – Dec
It is desirable to separate heifers during bulling and calving and for mating 4 to 6 weeks earlier
than the cows to allow closer supervision during calving. Appropriate calving time is 6-8 weeks
before adequate green grazing can be expected. Calves born later than this are too small to
utiIise fully the milk potential of its dam grazing on the early green lush. The late calf is
susceptible to scours, sweating sickness and parasites. Therefore, it is clear that calving season
should be centred approximately 2 months before adequate green grazing can be expected.
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