Scanning percentages for ewes can be recorded in two different ways, Short Scanning or Long Scanning.
If you only have a short scanning percentage, the Short to Long Scan calculator can be used to calculate a theoretical long scanning figure based on your short scanning figures. While this will not be as accurate as a physical long scan, it will give a very good indication of what an equivalent long scan % would be.
Note. This calculator is based on theoretical numbers. Where your short scanning multiple % is a very high proportion of your flock, the calculated long scanning % can become unrealistic.
Ewes are scanned, and results recorded as: dries, singles, multiples (where multiples are all treated as being twins)
Example: 50(8%) dries + 100(15%) singles + 500(77%) multiples
= 1,100 potential lambs (169%)
Short scanning is less accurate and, in all probability, is likely to underestimate the true scanning %.
Ewes are scanned, and results are recorded as dries, singles, twins, triplets, quads
Example: 50(8%) dries + 100(15%) singles + 500 multiples - made up of 702(54%) twins + 429(22%) triplets + 24(1%) quads
= 1,255 potential lambs (193%)
Using long scanning percentages when calculating on farm performance will provide a more accurate measure of true performance.