Question.
A farmer has 200-cow self-replacing herd. The normal calving percentage is 80 per cent. The mortality rate is 5 per cent on all animals. Male calves are sold as weaners. Twenty (20) cull cows are sold each year. The farmer wants you to work out how many heifers to carry through the system so that he can replace the cull cows.
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Category of livestock
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Start of year
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purchases
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Transfer in
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births
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Total sources
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No.
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No.
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No.
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from
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No.
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No.
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Cows
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Repl. Heifers
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Weaner heifers
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Weaner steers
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calves
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total
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Category of livestock
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deaths
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Transfers out
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sales
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End of year
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Total uses
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No.
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No.
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To
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No.
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No
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No
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Cows
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Repl. Heifers
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Weaner heifers
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Weaner steer
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Calves
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total
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