Tool 9.7 Ewe retention and culling plan
Use this table to establish how many ewe lamb/hoggets to retain and how many to class out (cull).
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A
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Total ewes joined |
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B
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Marking percentage (convert % to decimal e.g. 98% = 0.98) |
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C
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Weaning percentage (convert % to decimal e.g. 100% = 1) |
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D |
Number of lamb/hogget ewes available = ((A x B) x C) / 2 |
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E
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Number of adult ewes in the year groups |
2 years |
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3 years |
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4 years |
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5 years |
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6 years |
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7 years |
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8 years |
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Total |
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F
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Number of adult ewes in the flock |
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G
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The oldest year group joined? |
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H
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Number of adult ewes culled for age |
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I
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Number of adult ewes culled for other reasons (e.g., reproductive performance, structure, flystrike, etc.) |
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J
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Number of adult ewes culled from the flock |
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K
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Adult ewe mortality percentage |
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L
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Number of adult ewes to replace or number of ewe lamb/hoggets to retain = J + (E x K) |
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M
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Ewe lamb/hogget retention percentage |
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Note: if retention (M) is over 100% you require more than produced to maintain flock numbers
Note: if retention (M) is less than 50% consider what other aspects of the calculation you may be able to tweak to improve rates of genetic progress towards breeding objective (oldest year group joined, number of ewes culled for other reasons etc).
Source: AWI ClassiFly
