Metabolomics in the Livestock and Poultry

The metabolome is the collection of all small molecule metabolites, usually less than 1000 Da in molecular weight, in an organism or cell that participate in the metabolism of the organism and maintain its normal growth and development.

Metabolomics is a discipline that studies the collection of all small molecule metabolites in cells, tissues and organs, and indicates the biochemical status of an organism by qualitative and quantitative analysis of small molecule substances, and also looks for the correlation between metabolites and the physiopathology of the organism, changes in the genetic environment, etc.

Applications of metabolomics in the livestock and poultry industry

Using mass spectrometry to detect metabolites in biological samples such as serum, urine and tissues of different breeds (lines) and sexes of livestock and poultry, some small molecules can be screened as biomarkers to distinguish the breed (line) and sex, providing a theoretical basis for the characterization of different breeds (lines) and sexes of livestock and poultry with different traits.

Metabolic small molecules can reflect the physiological state and phenotype of the organism, and the use of metabolite phenotypes can characterize complex phenotypes more accurately.

In addition, marker metabolite screening for heavy economic traits in agricultural animals, and the application of marker metabolites to marker-assisted selection can improve selection accuracy.

During the development of livestock and poultry farming, the occurrence of diseases often has a great impact on the growth and economic efficiency of livestock and poultry. However, the prevention and treatment of many diseases are very difficult. The organism often causes changes in the level of metabolites in the body before and after the occurrence of diseases, and the use of metabolomics allows for early diagnosis and the identification of disease-related biomarkers by testing biological samples such as blood and urine.

Serum metabolic fingerprinting of pre-lameness dairy cows (Dervishi et al., 2020).

Food quality is closely related to human health and food safety is of increasing concern. The good breeds produced by animal breeding mainly provide abundant food for humans. The volatile substances affecting food flavor are mainly small molecules with molecular weight less than 1000 Da. Previous macroscopic phenotyping methods were unable to characterize such specific phenotypes. With the increasing improvement of metabolomic detection platform and metabolite database, such substances can be accurately determined and studied in depth to provide metabolite phenotypes for flavor improvement of animal products. In addition, the metabolome can also provide rapid and accurate detection of chemical contaminants that are present in food at very low levels or difficult to isolate, as well as meat adulteration.

Metabolomics analysis strategies

The strategies chosen for metabolomic assays vary widely depending on the purpose of the assay. Commonly used metabolomics strategies include untargeted metabolomics, and targeted metabolomics.

• Untargeted metabolomics

Untargeted metabolomics, also known as discovery metabolomics, provides a comprehensive and systematic determination and analysis of endogenous substances in biological samples. The main features are unbiased analysis of metabolites in samples, the ability to characterize and screen the overall profile of small molecule substances in samples, and differential or pathway analysis by bioinformatic methods. Currently, untargeted metabolomics is widely used in various fields such as biomarker discovery, disease diagnosis, food flavor and safety.

• Targeted metabolomics

Targeted metabolomics analysis is a technique for the determination of a few, dozens, or classes of known target compounds of interest. Typically, untargeted metabolomics is used to discover differential metabolites, which are then further systematically validated using targeted metabolomics. Its main feature is the accurate identification and absolute quantification of metabolites of concern, which is more analytically relevant. Complementing the advantages of untargeted metabolomics, it is mainly applied in various research fields such as drug development, metabolic disease diagnosis and mechanism research.

Reference

1. Dervishi, E., Zhang, G., Zwierzchowski, G., et al. (2020). Serum metabolic fingerprinting of pre-lameness dairy cows by GC–MS reveals typical profiles that can identify susceptible cows. Journal of proteomics, 213, 103620.