Large scale phenotyping and genotyping of milk fine composition in the cow, goat and ewe

Abstract

PhénoFinlait gathers together the actors of dairy industries including cattle, sheep and goats; around a common goal: monitoring milk Fatty Acid (FA) and protein composition. Quantifying FA and proteins by a reliable and cheap large-scale method is necessary before identifying the ways to adapt this composition to consumers' and dairy processors' demand. The objectives of the project were i) to characterize precisely the milk composition, ii) to phenotype and genotype a large population of females all over France, and iii) to identify the genetic and feeding levers to control this composition. Mid infrared (MIR) spectrometry has been chosen to quantify milk FA and proteins. With this method, the four caseins, the two main whey proteins, and 15 to 27 FA can be quantified routinely and precisely. A large-scale data collection has been carried out in more than 1,500 commercial dairy cattle, goat and sheep farms. Dairy production, MIR spectra, female physiological stages, and composition of the diet were collected. More than 12,000 cows, goats and ewes were also genotyped. Finally, more than 800,000 representative data are stored in a database for the study of the genetic determinism of milk FA and protein composition, and the impact of husbandry.