Effects of Copper Supplementation on Lipid Oxidation and Meat Quality of Merino X Texel Lambs

Garrine CMLP^{1, 2,} , Fernandes TH³, Yoshikawa CYC¹, Correa LB¹, Bell V⁴, Netto AS¹ and Zanetti MA¹

¹College of Animal Science and Food Engineering, University of São Paulo, Brazil

²Universidade Lusófona, Lisbon, Portugal; & Veterinary Faculty, Eduardo Mondlane University, Maputo, Mozambique

³CIISA, Faculty of Veterinary Medicine, University of Lisbon, Portugal

⁴Faculdade de Farmácia, Universidade de Coimbra, Portugal

Cite this paper:
Garrine CMLP, Fernandes TH, Yoshikawa CYC, Correa LB, Bell V, Netto AS and Zanetti MA. Effects of Copper Supplementation on Lipid Oxidation and Meat Quality of Merino X Texel Lambs. Journal of Food and Nutrition Research. 2021; 9(10):539-549. doi: 10.12691/jfnr-9-10-6

Abstract

Two levels of copper sulphate and copper-methionine were evaluated on lipid oxidative stability in liver and Longissimus thoracis (LT) muscle, measured by thiobarbituric acid reactive substances (TBARS) and activities of superoxide dismutase (SOD) and glutathione peroxidase (GPx) in liver. 40 Merino x Texel lambs were randomly distributed into 5 treatments with 8 animals each. Treatments were: control, without copper addition; 10 or 30 mg of Cu/Kg DM complete diet in the form of Cu-sulphate or Cu-methionine. After 120 days period, animals were slaughtered and samples collected, for analyses on activities of SOD, GPx and TBARS in livers. LT muscle was collected for TBARS analysis at carcass dressing, 3 and 6 days after chilling at 4°C and 12 months after vacuum freezing. SOD and GPx activities were higher in animals receiving copper. TBARS values in muscle were higher in the control group at the time of boning but did not differ after 12 months of vacuum freezing. TBARS values in muscle during shelf life, with a linear increase over the days, did not vary. It was found that copper supplementation, even at considered toxic levels of 30mg/kg DM, plus 9mg/kg basal diet, resulted in increased hepatic concentration of liver antioxidant enzymes and showed no detrimental effects on muscle oxidative stability.

Keywords:
copper supplementation fatty acids lipid oxidation lamb meat

This work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

References:

[1]	Benton, T., Bieg, C., Harwatt, H., Pudasaini, R.& Wellesley, L. (2021). Food system impacts on biodiversity loss. Three levers for food system transformation in support of nature. https://www.chathamhouse.org/sites/default/files/2021-02/2021-02-03-food-system-biodiversity-loss-benton-et-al_0.pdf.
[2]	Zeng, Z., Centner, C., Gollhofer, A., & König, D. (2021). Effects of Dietary Strategies on Exercise-Induced Oxidative Stress: A Narrative Review of Human Studies. Antioxidants 2021, Vol. 10, Page 542, 10(4), 542.
[3]	Arshad, M. S., Sohaib, M., Ahmad, R. S., Nadeem, M. T., Imran, A., Arshad, M. U., Kwon, J.-H., & Amjad, Z. (2018). Ruminant meat flavor influenced by different factors with special reference to fatty acids. Lipids in Health and Disease, 17(1), 1-13.
[4]	Guerra, M., Cabrera, M., Abella, D., Saadoun, A., & Burton, A. (2019). Se and I status in pregnant ewes from a pastoral system and the effect of supplementation with Se and I or only Se on wool quality of lambs. Heliyon, 5(9).
[5]	Rast, L., Hernández-Jover, M., Martin, S., & Abuelo, A. (2020). An investigation of micronutrient supplementation in weaner lambs to improve growth rates in southeast Australia. Australian Veterinary Journal, 98(10), 478-485.
[6]	Listrat, A., Lebret, B., Louveau, I., Astruc, T., Bonnet, M., Lefaucheur, L., Picard, B., & Bugeon, J. (2016). How Muscle Structure and Composition Influence Meat and Flesh Quality. The Scientific World Journal, 2016.
[7]	Melkonian, E. A., & Schury, M. P. (2021). Biochemistry, Anaerobic Glycolysis. StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing;
[8]	Petrescu, D. C., Vermeir, I., & Petrescu-Mag, R. M. (2020). Consumer Understanding of Food Quality, Healthiness, and Environmental Impact: A Cross-National Perspective. International Journal of Environmental Research and Public Health, 17(1).
[9]	Gizaw, Z. (2019). Public health risks related to food safety issues in the food market: a systematic literature review. Environmental Health and Preventive Medicine, 24(1).
[10]	Giroux, S., Blekking, J., Waldman, K., Resnick, D., & Fobi, D. (2021). Informal vendors and food systems planning in an emerging African city. Food Policy, 103.
[11]	Mariani, M., Casabianca, F., Cerdan, C., & Peri, I. (2021). Protecting Food Cultural Biodiversity: From Theory to Practice. Challenging the Geographical Indications and the Slow Food Models. Sustainability, 13(9), 5265.
[12]	Domínguez, R., Pateiro, M., Gagaoua, M., Barba, F., Zhang, W., & Lorenzo, J. (2019). A Comprehensive Review on Lipid Oxidation in Meat and Meat Products. Antioxidants (Basel, Switzerland), 8(10).
[13]	Yim, D.-G., Ali, M., & Nam, K.-C. (2020). Comparison of Meat Quality Traits in Salami Added by Nitrate-freeSalts or Nitrate Pickling Salt during Ripening. Food Science of Animal Resources, 40(1), 11.
[14]	Pereira, A. L. F., & Abreu, V. K. G. (2018). Lipid Peroxidation in Meat and Meat Products. In Lipid Peroxidation Research. Intech Open.
[15]	Bessa, R. J. B., Portugal, P. V., Mendes, I. A., & Santos-Silva, J. (2005). Effect of lipid supplementation on growth performance, carcass and meat quality and fatty acid composition of intramuscular lipids of lambs fed dehydrated lucerne or concentrate. Livestock Production Science, 96(2-3), 185-194.
[16]	Papuc, C., Goran, G. V., Predescu, C. N., & Nicorescu, V. (2017). Mechanisms of Oxidative Processes in Meat and Toxicity Induced by Postprandial Degradation Products: A Review. Comprehensive Reviews in Food Science and Food Safety, 16(1), 96-123.
[17]	Hui, H. X., & Feng, T. (2018). Adipose Tissue as an Endocrine Organ. In Adipose Tissue. Intech Open.
[18]	Martínez-Sánchez, N. (2020). There and Back Again: Leptin Actions in White Adipose Tissue. International Journal of Molecular Sciences, 21(17), 6039.
[19]	Cedikova, M., Kripnerová, M., Dvorakova, J., Pitule, P., Grundmanova, M., Babuska, V., Mullerova, D., & Kuncova, J. (2016). Mitochondria in White, Brown, and Beige Adipocytes. Stem Cells International, 2016.
[20]	Barden, L., & Decker, E. (2016). Lipid Oxidation in Low-moisture Food: A Review. Critical Reviews in Food Science and Nutrition, 56(15), 2467-2482.
[21]	Purdom, T., Kravitz, L., Dokladny, K., & Mermier, C. (2018). Understanding the factors that affect maximal fat oxidation. Journal of the International Society of Sports Nutrition, 15(1).
[22]	Mehri, A. (2020). Trace Elements in Human Nutrition (II) - An Update. International Journal of Preventive Medicine, 11(1).
[23]	Ma, Z., Li, Y., Han, Z., Liu, Z., Wang, H., Meng, F., Liu, S., Chen, D., & Liu, M. (2021). Excessive Copper in Feed not Merely Undermines Animal Health but Affects Food Safety. Journal of Veterinary Science, 22(3), 1-12.
[24]	Royer, A., & Sharman, T. (2021). Copper Toxicity. In StatPearls. Stat Pearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK557456/.
[25]	FAS-Farm Advisory Services. (2019). Trace Element Supplementation in Sheep Flocks. www.fas.scot.
[26]	Gaetke, L., Chow-Johnson, H., & Chow, C. (2014). Copper: toxicological relevance and mechanisms. Archives of Toxicology, 88(11), 1929-1938.
[27]	Linder, M. C. (2020). Copper Homeostasis in Mammals, with Emphasis on Secretion and Excretion. A Review. International Journal of Molecular Sciences, 21(14), 4932.
[28]	Pierson, H., Muchenditsi, A., Kim, B., Ralle, M., Zachos, N., Huster, D., & Lutsenko, S. (2018). The Function of ATPase Copper Transporter ATP7B in Intestine. Gastroenterology, 154(1), 168-180.e5.
[29]	McArdle, H. J. (2021). Principles of Nutritional Assessment. Copper. https://www.izincg.org/new-blog-1/2021/5/23/principles-of-nutritional-assessment.
[30]	Gromadzka, G., Tarnacka, B., Flaga, A., & Adamczyk, A. (2020). Copper Dyshomeostasis in Neurodegenerative Diseases—Therapeutic Implications. International Journal of Molecular Sciences 2020, Vol. 21, Page 9259, 21(23), 9259.
[31]	Husain, N., & Mahmood, R. (2019). Copper (II) generates ROS and RNS, impairs antioxidant system and damages membrane and DNA in human blood cells. Environmental Science and Pollution Research International, 26(20), 20654-20668.
[32]	Ruiz, L. M., Libedinsky, A., & Elorza, A. A. (2021). Role of Copper on Mitochondrial Function and Metabolism. Frontiers in Molecular Biosciences, 8, 711227.
[33]	Gutiérrez-del-Río, I., López-Ibáñez, S., Magadán-Corpas, P., Fernández-Calleja, L., Pérez-Valero, Á., Tuñón-Granda, M., Miguélez, E. M., Villar, C. J., & Lombó, F. (2021). Terpenoids and Polyphenols as Natural Antioxidant Agents in Food Preservation. Antioxidants, 10(8), 1264.
[34]	Estévez, M. (2021). Critical overview of the use of plant antioxidants in the meat industry: Opportunities, innovative applications and future perspectives. Meat Science, 181(November), 108610.
[35]	Kalogianni, A. I., Lazou, T., Bossis, I., & Gelasakis, A. I. (2020). Natural Phenolic Compounds for the Control of Oxidation, Bacterial Spoilage, and Foodborne Pathogens in Meat. Foods, 9(6).
[36]	Akinmoladun, O. F., Fon, F. N., Mpendulo, C. T., & Okoh, O. (2020). Performance, heat tolerance response, and blood metabolites of water-restricted Xhosa goats supplemented with vitamin C. Translational Animal Science, 4(2), 1113-1127.
[37]	Joy, A., Dunshea, F. R., Leury, B. J., Clarke, I. J., DiGiacomo, K., & Chauhan, S. S. (2020). Resilience of Small Ruminants to Climate Change and Increased Environmental Temperature: A Review. Animals, 10(5), 867.
[38]	Vázquez-Armijo, J. F., Rojo, R., López, D., Tinoco, J. L., González, A., Pescador, N., & Domínguez-Vara, I. A. (2011). Trace elements in sheep and goats reproduction: A review. Tropical and Subtropical Agroecosystems, 14(1).
[39]	Menzies, P., Boermans, H., Hoff, B., Durzi, T., & Langs, L. (2003). Survey of the status of copper, interacting minerals, and vitamin E levels in the livers of sheep in Ontario. The Canadian Veterinary Journal = La Revue Veterinaire Canadienne, 44(11), 898-906.
[40]	López-Alonso, M. (2012). Trace Minerals and Livestock: Not Too Much Not Too Little. ISRN Veterinary Science, 2012, 1-18.
[41]	Garrine, C., Yoshikawa, C., Conti, R., Correa, L., Pugine, S., Tchamo, C., Pondja, A., Balieiro, J. de C., & Zanetti, M. (2019). Effects of different sources and levels of copper on lipid metabolism in Merino × Texel lambs. Meat Science, 155, 85-90.
[42]	Chartier, C., Etter, E., Hoste, H., Pors, I., Koch, C., & Dellac, B. (2000). Efficacy of copper oxide needles for the control of nematode parasites in dairy goats. Veterinary Research Communications, 24(6), 389-399.
[43]	Biscarini, F., Palazzo, F., Castellani, F., Masetti, G., Grotta, L., Cichelli, A., & Martino, G. (2018). Rumen microbiome in dairy calves fed copper and grape-pomace dietary supplementations: Composition and predicted functional profile. PLOS ONE, 13(11), e0205670.
[44]	Miller, K., Vicentini, F., Hirota, S., Sharkey, K., & Wieser, M. (2019). Antibiotic treatment affects the expression levels of copper transporters and the isotopic composition of copper in the colon of mice. Proceedings of the National Academy of Sciences of the United States of America, 116(13), 5955-5960.
[45]	Goselink, R. M. A. (2015). Rumen By-Pass Copper “Koper voorbij de Pens.” www.wageningenUR.nl/livestockresearch.
[46]	McDowell, L. R. (1992). Minerals in animal and human nutrition. Academic Press.
[47]	National Research Council. (2001). Nutrient Requirements of Dairy Cattle (Seventh Re). National Academies Press.
[48]	Páleníková, I., Hauptmanová, K., Pitropovská, E., Páleník, T., Husáková, T., Pechová, A., & Pavlata, L. (2014). Copper metabolism in goat-kid relationship at supplementation of inorganic and organic forms of copper. Czech Journal of Animal Science, 59(5), 201-207.
[49]	de Souza, C., de Azevedo, P., & Seabra, L. (2018). Food safety in Brazilian popular public restaurants: Food handlers' knowledge and practices. Journal of food safety, 38(5), e12512.
[50]	Paglia, D., & Valentine, W. (1967). Studies on the quantitative and qualitative characterization of erythrocyte glutathione peroxidase. The Journal of Laboratory and Clinical Medicine, 70(1), 158-169.
[51]	Bradford, M. (1976). A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Analytical Biochemistry, 72(1-2), 248-254.
[52]	Lu, S. C. (2020). Dysregulation of glutathione synthesis in liver disease. Liver Research, 4(2), 64-73.
[53]	Saeed, O. A., Sazili, A. Q., Akit, H., Alimon, A. R., & Samsudin, A. A. (2019). Effects of Corn Supplementation into PKC-Urea Treated Rice Straw Basal Diet on Hematological, Biochemical Indices and Serum Mineral Level in Lambs. Animals: An Open Access Journal from MDPI, 9(10).
[54]	Cheng, J., Ma, H., Fan, C., Zhang, Z., Jia, Z., Zhu, X., & Wang, L. (2011). Effects of different copper sources and levels on plasma superoxide dismutase, lipid peroxidation, and copper status of lambs. Biological Trace Element Research, 144(1-3), 570-579.
[55]	Netto, A. S., Zanetti, M. A., Del Claro, G. R., Vilela, F. G., Melo, M. P. de, Correa, L. B., & Pugine, S. M. P. (2013). Copper and selenium supplementation in the diet of Brangus steers on the nutritional characteristics of meat. Revista Brasileira de Zootecnia, 42(1), 70-75.
[56]	Senthilkumar, P., Nagalakshmi, D., Reddy, Y. R., & Sudhakar, K. (2009). Effect of different level and source of copper supplementation on immune response and copper dependent enzyme activity in lambs. Tropical Animal Health and Production, 41(4), 645-653.
[57]	Gresakova, L., Venglovska, K., & Cobanova, K. (2016). Dietary manganese source does not affect Mn, Zn and Cu tissue deposition and the activity of manganese-containing enzymes in lambs. Journal of Trace Elements in Medicine and Biology : Organ of the Society for Minerals and Trace Elements (GMS), 38, 138-143.
[58]	Prashanth, Kattapagari, K. K., Chitturi, R. T., Baddam, V. R. R., & Prasad, L. K. (2015). A review on role of essential trace elements in health and disease. Journal of Dr. NTR University of Health Sciences, 4(2), 75.
[59]	Boriskin, P., Gulenko, O., Devyatkin, A., Karimova, R., Leonov, V., & Pavlova, O. (2020). Correlation of the distribution of antioxidant enzyme concentrations in blood serum and heart tissue in rats. BIO Web Conf., 17(1), 00234.
[60]	Uriu-Adams, J., & Keen, C. (2005). Copper, oxidative stress, and human health. Molecular Aspects of Medicine, 26(4-5), 268-298.
[61]	Micheloud, J. F., Martinez, G. M., Araoz, V., Suarez, V. H., Rosa, D. E., & Matioli, G. A. (2021). Niveles séricos de minerales en hembras bovinas en un establecimiento de la región del Chaco semiárido salteño. RIA, 47(1), 134-139.
[62]	DiNicolantonio, J., Mangan, D., & O’Keefe, J. (2018). Copper deficiency may be a leading cause of ischaemic heart disease. Open Heart, 5(2).
[63]	Espinosa, C. D., & Stein, H. H. (2021). Digestibility and metabolism of copper in diets for pigs and influence of dietary copper on growth performance, intestinal health, and overall immune status: a review. Journal of Animal Science and Biotechnology 2021 12:1, 12(1), 1-12.
[64]	Schwarz, M., Lossow, K., Schirl, K., Hackler, J., Renko, K., Kopp, J. F., Schwerdtle, T., Schomburg, L., & Kipp, A. P. (2020). Copper interferes with selenoprotein synthesis and activity. Redox Biology, 37, 101746.
[65]	Giustarini, D., Dalle-Donne, I., Tsikas, D., & Rossi, R. (2009). Oxidative stress and human diseases: Origin, link, measurement, mechanisms, and biomarkers. Critical Reviews in Clinical Laboratory Sciences, 46(5-6), 241-281.
[66]	Sanajou, S., & Şahin, G. (2021). Mechanistic Biomarkers in Toxicology. Turkish Journal of Pharmaceutical Sciences, 18(3), 376.
[67]	Dworzański, J., Strycharz-Dudziak, M., Kliszczewska, E., Kiełczykowska, M., Dworzańska, A., Drop, B., & Polz-Dacewicz, M. (2020). Glutathione peroxidase (GPx) and superoxide dismutase (SOD) activity in patients with diabetes mellitus type 2 infected with Epstein-Barr virus. PLOS ONE, 15(3), e0230374.
[68]	Papastergiadis, A., Mubiru, E., Langenhove, H. Van, & Meulenaer, B. De. (2012). Malondialdehyde measurement in oxidized foods: evaluation of the spectrophotometric thiobarbituric acid reactive substances (TBARS) test in various foods. Journal of Agricultural and Food Chemistry, 60(38), 9589-9594.
[69]	Leon, J. A. D. De, & Borges, C. (2020). Evaluation of Oxidative Stress in Biological Samples Using the Thiobarbituric Acid Reactive Substances Assay. Journal of Visualized Experiments : JoVE, 2020(159).
[70]	Khoshnoudi-Nia, S., & Moosavi-Nasab, M. (2019). Comparison of various chemometric analysis for rapid prediction of thiobarbituric acid reactive substances in rainbow trout fillets by hyperspectral imaging technique. Food Science & Nutrition, 7(5), 1875.
[71]	Amaral, A. B., Silva, M. V. da, & Lannes, S. C. da S. (2018). Lipid oxidation in meat: mechanisms and protective factors – a review. Food Science and Technology, 38, 1-15.
[72]	Luza, S., & Speisky, H. (1996). Liver copper storage and transport during development: implications for cytotoxicity. The American Journal of Clinical Nutrition, 63(5), 812-820.
[73]	Scheller, J., Irvine, G., & Stillman, M. (2018). Unravelling the mechanistic details of metal binding to mammalian metallothioneins from stoichiometric, kinetic, and binding affinity data. Dalton Transactions (Cambridge, England : 2003), 47(11), 3613-3637.
[74]	Jan, A. T., Azam, M., Siddiqui, K., Ali, A., Choi, I., & Haq, Q. M. R. (2015). Heavy Metals and Human Health: Mechanistic Insight into Toxicity and Counter Defense System of Antioxidants. International Journal of Molecular Sciences, 16(12), 29592.
[75]	Knockaert, L., Berson, A., Ribault, C., Prost, P., Fautrel, A., Pajaud, J., Lepage, S., Lucas-Clerc, C., Bégué, J., Fromenty, B., & Robin, M. (2012). Carbon tetrachloride-mediated lipid peroxidation induces early mitochondrial alterations in mouse liver. Laboratory Investigation; a Journal of Technical Methods and Pathology, 92(3), 396-410.
[76]	Correa, L., Zanetti, M., Claro, G. Del, Melo, M. de, Rosa, A., & Netto, A. S. (2012). Effect of supplementation of two sources and two levels of copper on lipid metabolism in Nellore beef cattle. Meat Science, 91(4), 466-471.
[77]	Sotler, R., Poljšak, B., Dahmane, R., Jukić, T., Jukić, D. P., Rotim, C., Trebše, P., & Starc, A. (2019). Prooxidant activities of antioxidants and their impact on health. Acta Clinica Croatica, 58(4), 726.
[78]	Gaschler, M., & Stockwell, B. (2017). Lipid peroxidation in cell death. Biochemical and Biophysical Research Communications, 482(3), 419-425.
[79]	Iuchi, K., Takai, T., & Hisatomi, H. (2021). Cell Death via Lipid Peroxidation and Protein Aggregation Diseases. Biology, 10(5), 399.
[80]	EFSA. (2018). Summary of Tolerable Upper Intake Levels-version 4 (Overview on Tolerable Upper Intake Levels as derived by the Scientific Committee on Food (SCF) and the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA). https://www.efsa.europa.eu/sites/default/files/assets/UL_Summary_tables.pdf.
[81]	Cummins, K., Solaiman, S., & Bergen, W. (2008). The effect of dietary copper supplementation on fatty acid profile and oxidative stability of adipose depots in Boer x Spanish goats. Journal of Animal Science, 86(2), 390-396.
[82]	Dønnem, I., Randby, Å. T., Hektoen, L., Avdem, F., Meling, S., Våge, Å. Ø., Ådnøy, T., Steinheim, G., & Waage, S. (2015). Effect of vitamin E supplementation to ewes in late pregnancy on the rate of stillborn lambs. Small Ruminant Research, 125, 154-162.
[83]	Leal, L. N., Beltrán, J. A., Bellés, M., Bello, J. M., Hartog, L. A. den, Hendriks, W. H., & Martín-Tereso, J. (2020). Supplementation of lamb diets with vitamin E and rosemary extracts on meat quality parameters. Journal of the Science of Food and Agriculture, 100(7), 2922.
[84]	Bellés, M., Campo, M. D. M., Roncalés, P., & Beltrán, J. (2019). Supranutritional doses of vitamin E to improve lamb meat quality. Meat Science, 149, 14-23.
[85]	Baldi, G., Chauhan, S., Linden, N., Dunshea, F., Hopkins, D., Rossi, C. S., Dell’Orto, V., & Ponnampalam, E. (2019). Comparison of a grain-based diet supplemented with synthetic vitamin E versus a lucerne (alfalfa) hay-based diet fed to lambs in terms of carcass traits, muscle vitamin E, fatty acid content, lipid oxidation, and retail colour of meat. Meat Science, 148, 105-112.
[86]	U.S. Department of Health & Human Services. (2021). Cold Food Storage Chart. FoodSafety.Gov. https://www.foodsafety.gov/food-safety-charts/cold-food-storage-charts.
[87]	Mitrus, O., Żuraw, M., Losada-Barreiro, S., Bravo-Díaz, C., & Paiva-Martins, F. (2019). Targeting Antioxidants to Interfaces: Control of the Oxidative Stability of Lipid-Based Emulsions. Journal of Agricultural and Food Chemistry, 67(11), 3266-3274.
[88]	Choi, M., Abduzukhurov, T., Park, D., Kim, E., & Hong, G. (2018). Effects of Deep Freezing Temperature for Long-term Storage on Quality Characteristics and Freshness of Lamb Meat. Korean Journal for Food Science of Animal Resources, 38(5), 959-969.
[89]	Huang, Y., Wang, Y., Spears, J., Lin, X., & Guo, C. (2013). Effect of copper on performance, carcass characteristics, and muscle fatty acid composition of meat goat kids. Journal of Animal Science, 91(10), 5004-5010.
[90]	Vyncke, W. (1975). Evaluation of the Direct Thiobarbituric Acid Extraction Method for Determining Oxidative Rancidity in Mackerel (Scomber scombrus L.). Fette, Seifen, Anstrichmittel, 77(6), 239-240.
[91]	Kasapidou, E., Wood, J., Richardson, R., Sinclair, L., Wilkinson, R., & Enser, M. (2012). Effect of vitamin E supplementation and diet on fatty acid composition and on meat colour and lipid oxidation of lamb leg steaks displayed in modified atmosphere packs. Meat Science, 90(4), 908-916.
[92]	Kershaw, J., & Mattes, R. (2018). Nutrition and taste and smell dysfunction. World Journal of Otorhinolaryngology - Head and Neck Surgery, 4(1), 3-10.
[93]	Zeece, M. (2020). Introduction to the chemistry of food. Academic Press.
[94]	Saylor, W., & Leach, R. (1980). Intracellular distribution of copper and zinc in sheep: effect of age and dietary levels of the metals. The Journal of Nutrition, 110(3), 448-459.
[95]	Eckert, G. E., Greene, L. W., Carstens, G. E., & Ramsey, W. S. (1999). Copper status of ewes fed increasing amounts of copper from copper sulphate or copper proteinate. Journal of Animal Science, 77(1), 244-249.
[96]	Vyncke, W. (1970). Direct Determination of the Thiobarbituric Acid Value in Trichloracetic Acid Extracts of Fish as a Measure of Oxidative Rancidity. Fette, Seifen, Anstrichmittel, 72(12), 1084-1087.
[97]	Vona, R., Pallotta, L., Cappelletti, M., Severi, C., & Matarrese, P. (2021). The Impact of Oxidative Stress in Human Pathology: Focus on Gastrointestinal Disorders. Antioxidants 2021, Vol. 10, Page 201, 10(2), 201.