Hiii everybody! I have been told that the female Siberian Tiger at Banham (the name escapes me) is genetically the fourth 'best' Siberian Tiger in the world! Now, I am not entirely sure what they mean by 'best' it could be that she is genetically the fourth 'cleanest'... I dont know. Byyyee Everybody!
It probably means she is fourth with the lowest represented genes in the captive population, which means she is genetically important to breed from.
I don't really know what I'm talking about, but I've got some notes to hand... each animal in a breeding programme is assigned a Mean Kinship Value (MK) which takes into account its relationship to all other members - this aims to equalize wild-caught founder contributions to the gene pool. A never-bred founder animal would have a MK of 0. Another statistical tool used alongside Mean Kinship is Kinship Value (KV) - this represents the breeding value of an animal when variables such as age of close relations (they may be past breeding age) is taken into account. KV would try to iron out anomalies which could be produced if relying wholly on MK only (e.g. a brother & sister could theoretically be thrown up as breeding partners by MK analysis). When ascertaining your 'league table' of breeders there are other variables to take into account; you would avoid immediate linkage of rare & common genomes, for instance, because this would be like throwing away your rare genes on mongrel animals (to put it crudely). Instead you would try and link rarer genomes and gradually pass the rare genes through your population. As an overall strategy you would have to decide whether you were trying to maintain your tigers as an Evolutionary (or Geographically) Significant Unit, or perhaps trying to supplement a small gene pool with new material (e.g. South Chinese tigers being supplemented with Siberian genes). Animals can also be assigned an Inbreeding Coefficient (the probability that shared genes were received from a common ancestor), and founder animals can be given a Founder Importance Coefficient (how well represented a certain founder's genes are represented in the group), which will also impact on that animal's descendants. All these factors and others will have to be taken into account, along with more mundane considerations such as temperament of animals and geographical distance between potential breeding pairs. At the end of the day there would be more than one way of saying which was the best-bred or most eligible breeder - and theoretical tigers are only 'paper tigers'!
