Recent studies have shown a relationship betweenthe level of the sialic acid (Sia), N-glycolylneuraminic acid(Neu5Gc) in red meat and its risk in cancer, cardiovascularand inflammatory diseases. Unresolved is the Sia concentrationin different organs of piglets during development. Our aim wasto determine the level of free and conjugated forms of Neu5Gc,N-acetylneuraminic acid (Neu5Ac) and ketodeoxynonulsonicacid (Kdn) in fresh and cooked spleen, kidney, lung, heart, liver,and skeletal muscle from 3-days-old (n = 4'8), 38-days-old(n = 10) and adult piglets (n = 4) by LC-MS/MS. Our findingsshow: (1) Lung tissue from 3 days-old piglets contained thehighest level of total Sia (14.6 Âµmol/g protein) compared withother organs or age groups; (2) Unexpectedly, Neu5Gc was themajor Sia in spleen (67'79 %) and adult lung (36'49 %) whilefree Kdn was the major Sia in skeletal muscle. ConjugatedNeu5Ac was the highest Sia in other organs (61'84 %); (3)Skeletal muscle contained the lowest concentration ofNeu5Gc in fresh and cooked meat; (4) Kdn accounted for<5 % of the total Sia in most organs; (5) During development,the total Sia concentration showed a 44'79 % decrease in allorgans; (6) In adult piglets, the high to low rank order of totalSia was lung, heart, spleen, kidney, liver and skeletal muscle. Inconclusion, the high level of Neu5Gc in all organs compared toskeletal muscle is a potential risk factor suggesting that dietaryconsumption of organ meats should be discouraged in favor ofmuscle to protect against cancer, cardiovascular and other inflammatorydiseases.