A Technological Breakthrough at the Service of Breeds and Farmers
The arrival of genomics
With the arrival of genomics a vast research field has been opened up to understand the genetic determinism of characteristics expressed by animals (phenotype). The incorporation of these advances into breeding schemes represents a real revolution. Genomic selection makes the best use of information from the analysis of DNA obtained using new genotyping technologies (DNA mapping).
Of course the first selection programmes came before access to the genome. For decades they operated by relating phenotypes (performances) with the family relationships of animals (genealogies), particularly due to advances in statistical models. Only major genes such as “polled”, “double-muscle carcass”, the gene for casein and for some weights could be located.
As for genomic selection it opens up new possibilities with, in particular, more accurate indexing of functional aptitudes (fertility, mastitis resistance, ease of births, etc.). With genomics a capacity for the global assessment of the genetic value of an animal now seems possible, in addition to the information accumulated in standard assessments. An animal can now be assessed without necessarily having to wait until it produces progeny. Its circulation in the programmes can therefore happen much earlier.
In just a few years genomics has considerably changed the selection and genetics sector and has made it possible:
- To widen the range of fathers of bulls
- To assess new criteria more accurately (estimated gain of 20%) whilst reducing the costs of breeding schemes (and therefore the production of doses)
- To reduce the generation interval
- To select bulls from a much larger group of candidates
- To explore characteristics which are difficult or impossible to select by the standard route because they are rarely inherited
- To improve herds either by the male or the female route
- To know the genetic value of an animal from birth and thus avoid progeny testing, a long, costly process
- To provide new information, greater diversity of breeding animals, particularly by the female route for breeds with small numbers
- To open up numerous possibilities for improvement by a better understanding of some genetic determinisms such as resistance to certain diseases
- To share reference populations between breeds to predict the genetic value of an individual of a given breed from reference populations for all the other breeds for which the characteristic is available,
Other dairy breeds, as well as the meat breeds and sheep and goats, benefit from the assets of the genomic revolution. Genomic assessments will be extended to new criteria which could not be taken into account in standard breeding schemes: fine components of milk having beneficial or negative effects on human health (fatty acids, etc.), resistance to diseases, meat quality (tenderness, marbling, flavours, etc.).
Programmes therefore aim to establish predictions concerning specific characteristics. This is the case for Phénofinlait for the fine milk composition for 20,000 genotyped cows, goats and ewes, and for Qualvigène for quality analysis of meat from more than 3000 genotyped young cattle.
France was one of the first countries to have its genomic evaluation methods validated internationally by Interbull. This place at the top of genomics selection is the fruit of a long-standing collaboration between Allice, the selection companies it unites, the Institut de l’Elevage and Institut National de la Recherche Agronomique (INRA) for basic research.
In June 2009 access to this new generation of genetic information was opened to all farmers, with the potential to have their females genotyped for the Holstein, Montbéliarde and Normande breeds. All the characteristics assessed by progeny now benefit from genomic assessment: milk production (milk quality and quantity), morphology of animals and functionalities (aptitudes making it possible to reduce production costs: female fertility, mastitis resistance, etc.).
In the Holstein breed the range of bulls has significant genetic diversity after a long period dominated by the sons of a very small number of sires. This range includes breeding animals with a high global summary index (ISU) and also includes bulls with other sought-after criteria (red colour, polled, etc.).
The Montbéliarde and Normande breeds also benefit from a range enriched with recent new pedigrees with profiles highlighting the characteristics of the mix of these two breeds.