Hematologic, Serum Biochemical Parameters, Fatty Acid and Amino Acid of Longissimus dorsi Muscles in Meat Quality of Tibetan Sheep

Abstract

Background : Reference values are very important in clinical management of diseased animal. The mutton quality char­acteristics not only could reflect the breed of sheep, but also allow for a selection of improved meat quality in the breed analyzed with more attractive sensory attributes. The aim of this study was to establish reference values for commonly used hematologic and biochemical parameters and evaluating the amino acid and fatty acid composition of meat quality traits of Tibetan sheep. Materials, Methods & Results : A total of 80 Tibetan sheep were randomly selected. Blood samples were collected used for hematological and biochemical analysis. The contents of mineral elements in serum were also measured. The animals were slaughtered according to commercial procedures. The mutton samples were removed from the Longissimus dorsi (LD) muscles used for amino acid and fatty acid composition analyzed. We have established a locally relevant reference parameters for commonly used hematological and biochemical tests. Most hematological and serum biochemical values were similar to those of yaks and camels, but the Hemoglobin (HGB) concentration was a little higher. The concentrations of Cu, Zn and Se were remarkably lower than critical values in the present study. LD muscle in Tibetan sheep had a higher proportion of total PUFA. We found a large amount of Glu, Lys, Asp, Leu and Arg in the LD muscle of Tibetan sheep. Discussion : Hematological and biochemical parameters are useful tools in measuring the physiological status of animals because they may provide information for diagnosis and prognosis of diseases. Tibetan sheep has survived for millions of generations in this low oxygen condition on the plateau. Tibetan sheep must have evolved exceptional mechanisms to adapt to this extremely inhospitable habitat. The study about Tibetan sheep will undoubtedly facilitate the discovery of potential molecular mechanisms of high-altitude adaptation. In the present study of the Tibetan sheep, all the hematolo­gical parameters referring to the erythrocyte and leukocyte series and also to the blood platelet counting were within the reference intervals considered as normal for the ovine species. The hematological results for Tibetan sheep were basically within the reference ranges for other ruminants, including yaks, Przewalski’s, Tibetan gazelles and camels. Trace element deficiency and unbalanced distribution is a major problem in the QTP, which has caused enormous economic loss to the herdsmen. The concentrations of Cu, Zn and Se were remarkably lower than critical values in the present study. Fatty acid composition plays an important role in meat quality, not only in the flavor quality, but also in the nutritional value of meat. Meanwhile, fatty acid analysis can be also used to evaluate the quality of animal meat. LD muscle in Tibetan sheep had a higher proportion of total PUFA, which were considered as flavor precursors of meat. This provides an evidence for that Chinese indigenous sheep show better mutton flavor intensity. Amino acids are the fundamental units of protein, and amino acid content plays an important role in meat quality by providing nutritive value and flavour characteristics. We found a large amount of Glu, Lys, Asp, Leu and Arg in the LD muscle of Tibetan sheep. The fatty acid and amino acid of LD muscles not only could reflect the character of Tibetan sheep mutton, but also allow for a selection of improved meat quality in the breed analyzed with more attractive sensory attributes.