1) Population size min & max: In some areas of the world it can be difficult to estimate population size. For this reason, minimum and maximum estimates are used.
2) Annual growth rate: estimated as: anti-log((log(no. of breeding ♀ in most recent year of reporting) -log(no. of breeding ♀ of report used for growth rate estimate))/((year of most recent report)-(year of report used for growth rate estimate))). The report used for growth rate estimate is the report at least 5 years back from, and closest to, the most recent report.
3) Ne: Two alternative estimates of effective population size (Ne) are presented in the table. The first, Ne (no selection), is calculated according to the formula Ne=(4MF/(M+F)) (Wright, S. 1931, Genetics, vol. 16: 97-159), where M and F are respectively the number of breeding males and females. Ne is not shown if insufficient data are available for estimation.
4) Expected inbreeding rate per year: is calculated as (1/(2xNe)) x (1/generation interval), where Ne is the effective population size assuming mass selection. The following species generation intervals are used: horse/ass 10 years; cattle/buffalo 5 years; sheep/goat 4 years; pigs 2 years (Groeneveld et al. 2009, Leroy et al. 2013). Inbreeding rate is not shown if insufficient data are available to estimate it.
5) Risk status: is currently computed in different ways, depending on criteria and thresholds considered. A revision of current systems is underway in order to achieve a uniform system across institutions. At this point of time, the table shows risk status following the criteria currently used by FAO and risk status following the criteria used by EAAP. Risk status is blank if insufficient data are available to estimate it. "Risk status FAO - Global level" is computed considering all breeds with the same transboundary name as one breed.
For information on FAO criteria, please refer to http://www.fao.org/3/i3327e/i3327e.pdf
The EAAP criteria is based on expected cumulated inbreeding in the next 50 years and is applicable only to the Cattle, Buffalo, Sheep, Goat, Horse, Ass and Pigs breeds. A breed is classified as:
In case the number of herds is less than 10 and the number of breeding females is below 500 the breed is assigned to the next higher EAAP endangerment class.