Genome-based improvement of bovine meat fat composition

Bovine meat contains a number of important nutrients such as proteins, energy, vitamins, minerals and essential fatty acids. However, red meat also contains relatively high levels of saturated fatty acids as compared to polyunsaturated acids. The fatty acid composition may have consequences for both human health and food quality, and the industry need to adjust their products to meet the consumers? demands for more healthy and palatable food. Meat fatty acid composition is regulated by a combination of genes and environmental factors. If we could identify the underlying genetic variants, we could select animals with desired nutritional values and increase the value and consumer satisfaction of beef. Obtaining genetic improvement for a trait requires suitable methods for trait recording (phenotyping). Meat fat composition is usually measured with gas chromatography, which is very expensive and therefore not suitable for routine recordings. However, meat and milk composition are regulated by many of the same mechanisms, and milk composition can be easily and inexpensively found with Fourier Transform Infrared Spectroscopy (FTIR). The current proposal aims to investigate if the genetic variants found to affect milk fat composition are also associated with meat fat composition. With this approach we can select animals with desired genotypic variants for milk content, and restrict trait recording and association testing to these animals. This approach is expected to yield results fast and inexpensively, and at the same time reveal if phenotypes for meat fatty acid composition can later be estimated from FTIR profiles of milk rather than from GC analyses of muscle. If so, this will provide an efficient tool for phenotyping of all breeding candidates.

Meat is generally regarded to have high nutritive value as it offers important sources of protein, energy, vitamins, minerals and essential fatty acids. However, red meat contains relatively high levels of saturated fatty acids as compared to polyunsaturated acids, and the effect of this imbalance is generally regarded as negative for the human health. Food quality aspects such as tenderness, flavour and colour are also affected by the fatty acid composition, and the industry needs to adjust their products to meet the consumers' demands for more healthy and palatable food. Meat fatty acid composition is regulated by a combination of environmental and genetic factors. By identifying the underlying genetic variants, one could select for optimum nutritional values and ultimately increase the value and consumer satisfaction of beef. Obtaining genetic improvement for a trait requires suitable methods for trait recording. Meat fat composition is usually measured with gas chromatography, which is highly expensive and not suitable for routine recordings. However, meat and milk composition are regulated by many of the same mechanisms, and milk composition can be easily and inexpensively estimated by Fourier Transform Infrared Spectroscopy (FTIR). The current proposal aims to investigate if the genes and polymorphisms found to affect milk fat composition are also associated with meat fat composition. With this approach we can select animals with desired genotypes for milk content, and restrict phenotyping and association testing to these animals. The animals have genotypes for ~50K markers, and will be genotyped and imputed further to detect causal variations. This approach is expected to yield results fast and inexpensively, and also reveal if phenotypes for meat fatty acid composition can later be estimated from FTIR profiles of milk rather than from GC analyses of muscle. If so, this will provide an efficient tool for phenotyping of all breeding candidates.