What is animal breeding all about?
- We keep animals for many reasons, and it’s a great mistake to think that making money is always the top priority.
- The human/animal relationship is very complex, and we often breed animals simply because we like them. This is the main criterion for breeders of companion animals.
- So the first job of the geneticist is to find out from breeders what their objectives are.
- With farm animals, the first aim is to produce a product for sale that meets market specifications, and secondly to breed replacements from the best parents so the flock, herd or population will keep on improving in performance.
- To do this we need to use the science of genetics.
What is genetics?
- Genetics is the science of heredity. It is concerned with the way characteristics or traits we see and measure in animals are inherited or passed on from one generation to the next.
- The science of genetics began in the late 1880s when an Austrian monk, Gregor Mendel discovered how color and shape in garden peas were inherited in mathematically predictable ways.
- This is called Mendelian genetics, and explains what happens with simple traits like coat colour, coat patterns, absence or presence of horns, jaw defects, and dwarfism.
- These are all traits controlled by very few genes, and predicting the outcome of matings is fairly simple.
- With farm animals, our main concerns are with complex traits like fertility, milk production and growth that are controlled my many genes in very complex combinations. So here we use “population genetics” based on mathematics and statistics to study what goes on.
Written by: Dr Clive Dalton