24
API AND TI
Tools to Simplify Selection
All-Purpose Index (API):
Evaluates sires for use on the entire cow herd (bred to both Angus first-calf heifers and mature cows) with the
portion of their daughters required to maintain herd size retained and the remaining heifers and
steers put on feed and sold grade and yield.
Terminal Index (TI)
: Evaluates sires for use on mature Angus cows with all offspring put on
feed and sold grade and yield.
Using API and TI:
First, determine which index to use; if you are keeping replacements use API, if not, use
TI. Then, just as with EPDs, zero in on the unit difference between bulls. (As described above, index units are
in dollars per cow exposed.) The difference can be used to determine how much a bull is worth compared to
another. Put another way, how much you can pay for one bull compared to another. For example, when buying
on all-purpose-type sire, you can quickly figure a bull scoring + 100 for API is worth an extra $6,000 over a +50
bull if both are exposed to 30 cows over 4 years ($50 diff. x 30 hd. x 4 yr. = $6,000). A percentile-ranking chart
is required to determine where a bull’s index value ranks him relative to other bulls in the breed. For more
detailed information about EPDs and $ indexes, visit
www.simmental.org
.
%
CE
BW WW YW MCE MLK MWW DOC CWT YG MRB
BF
REA
1 18.8 -3.8 81.5 131 14.6 32.7 66.6 16.8 51.5 -0.44 0.77 -0.1 0.95
2 17.7 -3.2 78.8 126.1 13.7 31.4 64.8 16 48.2 -0.41 0.7 -0.1 0.9
3 17.1 -2.9 77.1 122.9 13.2 30.6 63.6 15.5 46.2 -0.39 0.67 -0.09 0.87
4 16.6 -2.6 75.8 120.6 12.8 30 62.7 15.1 44.7 -0.38 0.64 -0.09 0.85
5 16.2 -2.4 74.7 118.7 12.4 29.5 62 14.8 43.4 -0.37 0.61 -0.08 0.82
10 14.8 -1.6 71 112.1 11.3 27.8 59.5 13.6 39.1 -0.33 0.53 -0.07 0.76
15 13.8 -1.1 68.6 107.6 10.5 26.7 57.9 12.9 36.3 -0.31 0.48 -0.07 0.71
20 13.1 -0.7 66.6 104.1 9.8 25.8 56.6 12.3 34 -0.29 0.43 -0.06 0.67
25 12.5 -0.4 65 101.1 9.3 25 55.5 11.8 32 -0.27 0.4 -0.06 0.64
30 11.9 0 63.4 98.4 8.8 24.3 54.4 11.3 30.2 -0.25 0.36 -0.05 0.61
35 11.4 0.2 62.1 95.9 8.4 23.7 53.5 10.9 28.6 -0.24 0.33 -0.05 0.58
40 10.8 0.5 60.7 93.5 8 23.1 52.6 10.5 27 -0.22 0.3 -0.05 0.56
45 10.4 0.8 59.4 91.2 7.6 22.5 51.8 10.1 25.5 -0.21 0.27 -0.04 0.54
50 9.9 1 58.2 88.9 7.2 21.9 50.9 9.8 24 -0.2 0.25 -0.04 0.51
55 9.4 1.3 56.9 86.6 6.7 21.3 50.1 9.4 22.6 -0.19 0.22 -0.04 0.49
60 8.9 1.6 55.6 84.3 6.3 20.7 49.2 9 21.1 -0.17 0.19 -0.03 0.46
65 8.4 1.8 54.3 81.9 5.9 20.1 48.3 8.6 19.5 -0.16 0.16 -0.03 0.44
70 7.9 2.1 52.9 79.4 5.5 19.5 47.4 8.2 17.9 -0.14 0.13 -0.03 0.41
75 7.3 2.4 51.4 76.7 5 18.8 46.4 7.7 16.1 -0.13 0.1 -0.02 0.38
80 6.7 2.8 49.7 73.6 4.5 18 45.2 7.2 14.1 -0.11 0.06 -0.02 0.35
85 5.9 3.2 47.8 70.1 3.8 17.1 43.9 6.6 11.8 -0.09 0.01 -0.01 0.31
90 5 3.7 45.3 65.7 3
16 42.3 5.9 8.9 -0.07 -0.04 -0.01 0.27
95 3.6 4.4 41.7 59.1 1.9 14.3 39.8 4.8 4.7 -0.03 -0.12 0
0.2
Avg
9.9 1 58.2 88.9 7.2 21.9 50.9 9.8 24 -0.2 0.25 -0.04 0.51
2013 Hybrid Simmental Percentile Table SC
1...,15,16,17,18,19,20,21,22,23,24 25