14.3 Assessing the risk status for breeds (2024)
- Tessa Jacobs
- Kor Oldenbroek
A lot of attention is given by FAO to define the risk status of breeds. That is not simply a matter of numbers of animals. Of course that is a main criterion, but there is more: are females only used for pure breeding or are they more or less used for crossbreeding? A decisive factor is the reproductive capacity of the breed: does a female produce hundreds of offspring per year as is the case in commercial poultry breeding or does a female produce on average one replacement in ten years as is the case in horses? FAO uses the criteria: not at risk, vulnerable, endangered and critical to qualify the risk status of a breed. In the figure below it can be seen how this works out for breeds of species with a high and low reproductive capacity:
The risk status of a breed can be linked to the risk of actual loss in genetic diversity, and, related to that, to the risk of increase in genetic defects and the decrease in ability to respond to fluctuation in the environment, here described as random events. The population becomes more vulnerable to changes in the environment because there is a risk that (almost) none of the animals carries the genes to cope with that. In a larger population with more genetic diversity, the probability that there are animals that can cope with the changes is much larger.
