title: Metabolomics evidences plasma and serum biomarkers differentiating two heavy pig breeds.
abstract: In pigs, many production traits are known to vary among breeds or lines. These traits can be considered end phenotypes or external traits as they are the final results of complex biological interactions and processes whose fine biological mechanisms are still largely unknown. This study was designed to compare plasma and serum metabolomic profiles between animals of two heavy pig breeds (12 Italian Large White and 12 Italian Duroc), testing indirectly the hypothesis that different genetic backgrounds might be the determining factors of differences observed on the level of metabolites in the analyzed biofluids between breeds. We used a targeted metabolomic approach based on mass spectrometric detection of about 180 metabolites and applied a statistical validation pipeline to identify differences in the metabolomic profiles of the two heavy pig breeds. Blood samples were collected after jugulation at the slaughterhouse and prepared for metabolomics analysis that was carried out using the Biocrates AbsoluteIDQ p180 Kit, covering five different biochemical classes: glycerophospholipids, amino acids, biogenic amines, hexoses and acylcarnitines. A statistical pipeline that included the selection of the most relevant metabolites differentiating the two breeds by sparse Partial Least Squares Discriminant Analysis (sPLS-DA) was coupled with a stability test and significance test determined with leave one out and permutation procedures. sPLS-DA plots clearly separated the pigs of the two investigated breeds. A few metabolites (a total of five metabolites considering the two biofluids) involved in key metabolic pathways largely contributed to these differences between breeds. In particular, a higher level of the sphingomyelins SM (OH) C14:1 (both in plasma and serum), SM (OH) C16:1 (in serum) and SM C16:0 (in serum) were observed in Italian Duroc than in Italian Large White pigs and the inverse was for the biogenic amine kynurenine (in plasma). The level of another biogenic amine (acetylornithine) was higher in Italian Large White than in Italian Duroc pigs in both analysed biofluids. These results provided biomarkers that could be important to understand the biological differences between these two heavy pig breeds. In particular, according to the functional role played by sphingomyelins in obesity-induced inflammatory responses, it could be possible to speculate that a higher level of sphingomyelins in Italian Duroc might be related to the higher interrmuscular fat deposition of this breed compared with the Italian Large White. Additional studies will be needed to evaluate the relevance of these biomarkers for practical applications in pig breeding and nutrition.
authors.affiliation: 1Department of Agricultural and Food Sciences,Division of Animal Sciences,University of Bologna,Viale G. Fanin 46,40127 Bologna,Italy.
authors.forename: S
authors.initials: S
authors.lastname: Bovo
authors.affiliation: 1Department of Agricultural and Food Sciences,Division of Animal Sciences,University of Bologna,Viale G. Fanin 46,40127 Bologna,Italy.
authors.forename: G
authors.initials: G
authors.lastname: Mazzoni
authors.affiliation: 2Department of Statistical Sciences 'Paolo Fortunati',University of Bologna,Via delle Belle Arti,40126 Bologna,Italy.
authors.forename: G
authors.initials: G
authors.lastname: Galimberti
authors.affiliation: 2Department of Statistical Sciences 'Paolo Fortunati',University of Bologna,Via delle Belle Arti,40126 Bologna,Italy.
authors.forename: D G
authors.initials: DG
authors.lastname: Calò
authors.affiliation: 3Department of Surgical and Medical Sciences,Endocrinology Unit,University of Bologna,Massarenti 9,40138 Bologna,Italy.
authors.forename: F
authors.initials: F
authors.lastname: Fanelli
authors.affiliation: 3Department of Surgical and Medical Sciences,Endocrinology Unit,University of Bologna,Massarenti 9,40138 Bologna,Italy.
authors.forename: M
authors.initials: M
authors.lastname: Mezzullo
authors.affiliation: 1Department of Agricultural and Food Sciences,Division of Animal Sciences,University of Bologna,Viale G. Fanin 46,40127 Bologna,Italy.
authors.forename: G
authors.initials: G
authors.lastname: Schiavo
authors.affiliation: 2Department of Statistical Sciences 'Paolo Fortunati',University of Bologna,Via delle Belle Arti,40126 Bologna,Italy.
authors.forename: A
authors.initials: A
authors.lastname: Manisi
authors.affiliation: 1Department of Agricultural and Food Sciences,Division of Animal Sciences,University of Bologna,Viale G. Fanin 46,40127 Bologna,Italy.
authors.forename: P
authors.initials: P
authors.lastname: Trevisi
authors.affiliation: 1Department of Agricultural and Food Sciences,Division of Animal Sciences,University of Bologna,Viale G. Fanin 46,40127 Bologna,Italy.
authors.forename: P
authors.initials: P
authors.lastname: Bosi
authors.affiliation: 1Department of Agricultural and Food Sciences,Division of Animal Sciences,University of Bologna,Viale G. Fanin 46,40127 Bologna,Italy.
authors.forename: S
authors.initials: S
authors.lastname: Dall'Olio
authors.affiliation: 3Department of Surgical and Medical Sciences,Endocrinology Unit,University of Bologna,Massarenti 9,40138 Bologna,Italy.
authors.forename: U
authors.initials: U
authors.lastname: Pagotto
authors.affiliation: 1Department of Agricultural and Food Sciences,Division of Animal Sciences,University of Bologna,Viale G. Fanin 46,40127 Bologna,Italy.
authors.forename: L
authors.initials: L
authors.lastname: Fontanesi
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D015415:Biomarkers / Q000097:blood / Q000652:urine; D001947:Breeding; D016002:Discriminant Analysis; D005260:Female; D007558:Italy; D008297:Male; D013058:Mass Spectrometry / Q000662:veterinary; D055432:Metabolomics; D010641:Phenotype; D013552:Swine / Q000502:physiology*
chemical_list: D000596:Amino Acids; D015415:Biomarkers
keywords: metabolic pathway; metabolites; molecular phenotypes; pig breeding; production traits