doi: 10.15389/agrobiology.2023.4.638eng

UDC: 636.4:619:616-092.19

Supported financially by Russian Science Foundation, project No. 19-16-00068-P



R.V. Nekrasov ✉, N.V. Bogolyubova, K.S. Ostrenko, M.G. Chabaev,
I.V. Kutyin, P.D. Lakhonin, A.A. Semenova, V.A. Pchelkina,
V.V. Nasonova, S.I. Loskutov, R.A. Rykov, Yu.A. Prytkov

Ernst Federal Research Center for Animal Husbandry, 60, pos. Dubrovitsy, Podolsk District, Moscow Province, 142132 Russia, e-mail (✉ corresponding author),,,,,,,,,,,

Nekrasov R.V.
Semenova A.A.
Bogolyubova N.V.
Phelkina V.A.
Ostrenko K.S.
Nasonova V.V.
Chabaev M.G.
Kutyin I.V.
Rykov R.A.
Lahonin P.D.
Prytkov Yu.A.

Final revision received July 14, 2023
Accepted August 7, 2023

A peculiarity of living organisms is the internal constancy maintained by self-regulation mechanisms. In higher animals, the functions of control and regulation of biochemical reactions are performed by the neuro-endocrine system. With its help the organism perceives various influences of external and internal environment and reacts to them by means of hormones. In this regard, biomarkers of stress level are primarily the content of hormones, as well as blood concentrations of metabolites and their correlation. The use of dihydroquercetin, vitamins C and E in nutrition can help to reduce the negative effects of stress. In the present work we have established for the first time the positive influence of additional feeding of antioxidant complex on the adaptation of pigs under stress by hormonal regulation and strengthening of antioxidant status of the organism. The aim of the work was to evaluate the effect of feeding a complex of adaptogens DHQEC (dihydroquercetin and vitamins E, C) on the biochemical status and productive qualities of pigs under stress modelling. Fattening experiments were performed on 34 pigs (Sus scrofa domesticus) F2 [(Large White × Landrace) × Duroc] (Ernst Federal Research Center for Animal Husbandry, 2022-2023). Body weight (BW) of piglets aged 99 days at the beginning of the experiment was 40.7-41.0 kg. The duration of the fattening period was 90 days. During the preliminary period, piglets were distributed into four groups by the paired-analogues method: I control (С-, without dietary DHQEC) (9 animals), II control (C+, with dietary DHQEC) (9 animals), III experimental (Е-, without dietary DHQEC) (8 animals), IV experimental (E+, with dietary DHQEC) (8 animals). Each stall sized 2.4×2.25 m (5.4 m2) with 1.05 m feeding front. That is, with four pigs per stall (groups Е- and E+) instead of 3 pigs per stall (groups С- and C+), there was a decrease in the stall area per pig from 1.8 to 1.35 m2, and the feeding front from 0.35 to 0.26 m (according to GOST 28839-2017, the norm is at least 0.3 m per pig). DHQEC contained DHQ (Ecostimul-2, AO Ametis, Russia; DHQ 72-73 %, 32 mg/kg of feed), vitamin E (INNOVIT E60, MEGAMIX, Russia, 10 mg/kg of feed), and vitamin C (Tiger C 35, Anhui Tiger Biotech Co., Ltd., China, 35 mg/kg of feed). Animals from groups C+ and E+ received dietary DHQEC (0.025 % by weight of mixed fodder) throughout the whole period of the tests. Young animals were weighed individually every decade. To assess the clinical, physiological and metabolic status of the organism at the end of the growing period, as well as during transfer to final fattening and before slaughter, blood samples were taken from the jugular vein in the morning before feeding. Calcium, phosphorus, magnesium, aspartate aminotransferase, alanine aminotransferase activity, alkaline phosphatase, total bilirubin, creatinine, cholesterol, glucose, total protein, albumin, chloride and urea were determined in blood serum. To assess antioxidant status, the total amount of free water-soluble antioxidants was determined amperometrically in serum samples. The serum concentrations of total and free thyroxine (T4t and T4f) and triiodothyronine (T3t and T3f), as well as thyroid hormone, cortisol, adrenaline, insulin-like growth factor-1, and melatonin were also determined by solid-phase enzyme-linked immunosorbent assay. BW of pigs after starvation was evaluated immediately before slaughter. After slaughter, the carcass was weighed, the slaughter yield, thickness of the skin, muscle eye area, and pH were determined 45 min after slaughter and after 24 h of storage. It was found that with increased competition for feed table, DHQEC provides a significant decrease in cortisol (p = 0.014) and adrenaline (p = 0.09) in piglets during the final fattening. Due to competition for feed, the melatonin concentration decreased (p = 0.01), while DHQEC in E+ group normalized the melatonin level to the values for the 1st and 2nd blood draws. Stress had a negative effect on some metabolic processes indicators of which are biochemical blood parameters (blood concentration of triglycerides, cholesterol, bilirubin, AsAT). At final fattening, there were significant shifts in the animal hormonal status. In piglets in groups C compared to E, the concentration of T4t (p = 0.02), T3t (p = 0.05), T3f (p = 0.004) decreased together with an increase in the thyroid hormone (TTG) production (p = 0.05). Dietary DHQEC somewhat smoothed the negative influence of the modelled factor. The lowest values of T4t, T4f, T3t, T3f were rebealed in the E+ group. It should be noted that the TTG content and integral thyroid index (ITI) in the E+ group decreased to 0.46 mME/l and 69.7 units vs. 0.51 mME/l and 263.8 units in the Е- group, while the conversion of T4f to T3f decreased 1.73 times. With increasing BW of animals (70 kg and more), the effect of limitation of machine area and feeding front was stronger, which was manifested in the decrease of ADG in the Е- group in the last fattening period (p < 0.05). Under the influence of DHQEC during the final fattening, there was a tendency to increase the amount of insulin-like growth factor-1 (IGF-1) in groups C+ and E+ compared to groups С- and Е- (163.7 and 162.8 vs. 141.0 and 142.1 ng/ml, respectively, p = 0.14), which correlates with higher ADG. The obtained results indicate that DHQEC supplementation, having antioxidant activity, can improve growth parameters and, apparently, exhibit tissue-specific regulation of IGF-IR mRNA transcription. At the end of the experiment there was an increase in the blood melatonin (MT) concentration in animals from groups С- and C+ (p < 0.05), and dietary DHQEC did not affect the change of this index. A statistically significant decrease in MT content in Е- and E+ groups compared to the control groups (292.2 and 179.8 pg/ml vs. 457.6 and 458.7 pg/ml, p = 0.01) should be noted. Therefore, competition for feed led to a decrease in this index, and feeding of DHQEC in E+ group normalised its values to those at the 1st and 2nd blood draws. Stress had a significant effect on the quality of production. The adaptogen-antioxidant complex DHQEC significantly improves the adaptive abilities of pigs and reduces the influence of stress factors on production performance.

Keywords: adaptogen, dihydroquercetin, vitamin, stress, young pigs, hormones, blood biochemistry, slaughter performance.



  1. Afinogenova S.A., Bulatov A.A., Goncharova V.N. Biokhimiya gormonov i gormonal’noy regulyatsii [Biochemistry of hormones and hormonal regulation]. Moscow, 1976 (in Russ.).
  2. Terlouw E.M.C., Arnould C., Auperin B., Berri C., Bihan-Duval E. Le, Deiss V., Lefèvre F., Lensink B.J., Mounier L. Pre-slaughter conditions, animal stress and welfare: current status and possible future research. Animal, 2008, 2(10): 1501-1517 CrossRef
  3. Durosaro S.O., Iyasere O.S., Ilori B.M., Oyeniran V.J., Ozoje M.O. Molecular regulation, breed differences and genes involved in stress control in farm animals. Domestic Animal Endocrinology, 2023, 82: 106769 CrossRef
  4. Lindblom S.C., Gabler N.K., Dilger R.N., Olson Z.F., Loving C.L., Kerr B.J. Influence of feeding thermally peroxidized soybean oil on oxidative status in growing pigs. Journal of Animal Science, 2018, 96(2): 545-557 CrossRef
  5. de Oliveira M.J.K., Melo A.D.B., Marçal D.A., Valini G.A. da C., Silva C.A., Veira A.M., Fraga A.Z., Arnaut P.R., Campos P.H.R.F., dos Santos L.S., Htoo J.K.K., Brand H.G., Hauschild L. Effects of lowering dietary protein content without or with increased protein-bound and feed-grade amino acids supply on growth performance, body composition, metabolism, and acute-phase protein of finishing pigs under daily cyclic heat stress. Journal of Animal Science, 2023, 101: skac387 CrossRef
  6. Ijiri M., Odo K., Sato M., Kawaguchi M., Fujimoto Y., Miura N., Matsuo T., Hou D.X., Yamato O., Tanabe T., Kawaguchi H. Potential biomarkers for chronic seasonal heat stress in kagoshima berkshire pigs reared in the subtropical region. Journal of Veterinary Research,2022, 66(2): 209-214 CrossRef
  7. Rey A.I., Almudena de-Cara, Calvo L., Puig P., Hechavarría T. Changes in plasma fatty acids, free amino acids, antioxidant defense, and physiological stress by oleuropein supplementation in pigs prior to slaughter. Antioxidants, 2020, 9(1): 56 CrossRef
  8. Miller D.B., O'Callaghan J.P. Neuroendocrine aspects of the response to stress. Metabolism, 2002, 51(6): 5-10 CrossRef
  9. Petrosus E., Silva E.B., Lay D. Jr., Eicher S. D. Effects of orally administered cortisol and norepinephrine on weanling piglet gut microbial populations and Salmonella passage. Journal of Animal Science, 2018, 96(11): 4543-4551 CrossRef
  10. Yu C.-H., Chen C.-Y., Chang C.-C. The immediate effects of weaning stress on the hypothalamus-pituitary-adrenal alteration of newly weaned piglets. Animal Physiology and Animal Nutrition, 2019, 103(4): 1218-1223 CrossRef
  11. Cassar-Malek I., Picard B., Kahl S., Hocquette J.F. Relationships between thyroid status, tissue oxidative metabolism, and muscle differentiation in bovine fetuses. Domestic Animal Endocrinology, 2007, 33(1): 91-106 CrossRef
  12. Bi C., Yin J., Yang W., Shi B., Shan A. Effects of dietary gγ-aminobutyric acid supplementation on antioxidant status, blood hormones and meat quality in growing-finishing pigs undergoing transport stress. J. Anim. Physiol. Anim. Nutr., 2020, 104(2): 590-596 CrossRef
  13. Kota S.K., Gayatri K., Jammula S., Meher L.K., Kota S.K., Krishna S.V.S., Modi K.D. Fetal endocrinology. Indian Journal of Endocrinology and Metabolism, 2013, 17: 568-579 CrossRef
  14. Gritsenko S., Belookov A., Belookova O., Derkho M., Sereda T., Vereshchaga O., Koruhov D., Fedoseeva N. Assessment of blood parameters of pigs of different breeds and its interrelation with lifetime animal performance indicators. International Journal of Advanced Science and Technology, 2020, 29(5s): 1411-1417.
  15. Wan X., Wang D., Xiong Q., Xiang H., Li H., Wang H., Liu Z., Niu H., Peng J., Jiang S., Chai J. Elucidating a molecular mechanism that the deterioration of porcine meat quality responds to increased cortisol based on transcriptome sequencing. Sci. Rep., 2016, 6(36589): 14 CrossRef
  16. Puppel K., Kapusta A., Kuczyńska B. The etiology of oxidative stress in the various species of animals, a review. Journal of the Science of Food and Agriculture, 2014, 95(11): 2179-2184 CrossRef
  17. Khaydarov Sh.T., Tuychiboev Zh., Zhamoldinov A., Dzhabbarova G.M.-K., Zaripova M.R., Yusupova U.R. Universum: khimiya i biologiya, 2021, 4(82">CrossRef (in Russ.).
  18. Kalyanaraman B. Teaching the basics of redox biology to medical and graduate students: Oxidants, antioxidants and disease mechanisms. Redox Biology, 2013, 1(1): 244-257 CrossRef
  19. Prevatto J.P., Torres R.C., Diaz B.L., e Silva P M.R., Martins M.A., Carvalho V.F. Antioxidant treatment induces hyperactivation of the HPA axis by upregulating ACTH receptor in the adrenal and downregulating glucocorticoid receptors in the pituitary. Oxidative Medicine and Cellular Longevity, 2017, 2017: 4156361 CrossRef
  20. Montanelli L., Benvenga S., Hegedüs L., Vitti P., Latrofa F., Duntas L.H. Drugs and other substances interfering with thyroid function. In: Thyroid diseases. Endocrinology. P. Vitti, L. Hegedüs (eds.). Springer, Cham, Switzerland, 2018 CrossRef
  21. Semenova A.A., Nasonova V.V., Kuznetsova T.G., Tunieva E.K., Bogolyubova N.V., Nekrasov R.V. PSIII-17 program chair poster pick: a study on the effect of dihydroquercetin added into a diet of growing pigs on meat quality. Journal of Animal Science, 2020, 98(S4): 364 CrossRef
  22. Semenova A.A., Kuznetsova T.G., Nasonova V.V., Nekrasov R.V., Bogolyubova N.V., Tsis E.Yu. Use of antioxidants as adaptogens fed to pigs (Sus scrofa domesticus Erxleben, 1777) (meta-analysis). Sel'skokhozyaistvennaya biologiya [Agricultural Biology], 2020, 55(6): 1107-1125 CrossRef
  23. Direktiva 2010/63/EC Evropeyskogo parlamenta i Soveta evropeyskogo soyuza po okhrane zhivotnykh, ispol’zuemykh v nauchnykh tselyakh [Directive 2010/63/EC of the European Parliament and of the Council on the protection of animals used for scientific purposes]. Available: No date.
  24. European Convention for the Protection of Vertebrate Animals used for Experimental and other Scientific Purposes (ETS № 123) (Strasburg, 18.03.1986). Available: No date.
  25. Ovsyannikov A.I. Osnovy opytnogo dela v zhivotnovodstve. [Fundamentals of experiments in animal husbandry. Tutorial]. Moscow, 1976 (in Russ.).
  26. Antonova V.S., Topuriya G.M., Kosilov V.I. Metodologiya nauchnykh issledovaniy v zhivotnovodstve: uchebnoe posobie [Methodology of scientific research in animal husbandry: textbook]. Orenburg, 2011 (in Russ.).
  27. Nekrasov R.V., Golovin A.V., Makhaev E.A., Anikin A.S., Pervov N.G., Strekozov N.I., Mysik A.T., Duborezov V.M., Chabaev M.G., Fomichev Yu.P., Gusev I.V. Normy potrebnostey molochnogo skota i sviney v pitatel’nykh veshchestvakh /Pod redaktsiey R.V. Nekrasova, A.V. Golovina, E.A. Makhaeva [Nutrient requirements for dairy cattle and pigs. R.V. Nekrasov, A.V. Golovin, E.A. Makhaev (eds.)]. Moscow, 2018 (in Russ.).
  28. Pirgozliev V., Westbrook C., Woods S., Mansbridge S.C., Rose S.P., Whiting I.M., Yovchev D., Atanasov A.G., Kljak K., Staykova G.P., Ivanova S., Karagecili M.R., Karadas F., Stringhini J.H. Feeding dihydroquercetin and vitamin E to broiler chickens reared at standard and high ambient temperatures. Archives of Animal Nutrition,2020, 74(6): 496-511 CrossRef
  29. Fomichev Y., Bogolyubova N., Nekrasov R., Chabaev M., Semenova A. Physiological aspects of using dihydroquercetin in intensively growing young pigs diets. In: Fundamental and applied scientific research in the development of agriculture in the Far East (AFE-2021). AFE 2021. Lecture notes in networks and systems, vol. 354. A. Muratov, S. Ignateva (eds.). Springer, Cham, 2022, 354: 507-520 CrossRef
  30. Zhou Y., Chen L., Han H., Xiong B., Zhong R., Jiang Y., Liu L., Sun H., Tan J., Cheng X., Schroyen M., Gao Y., Zhao Y., Zhang H. Taxifolin increased semen quality of Duroc boars by improving gut microbes and blood metabolites. Front Microbiol., 2022, 13: 1020628 CrossRef
  31. Zou Y., Wei H., Xiang Q.-H., Wang J., Zhou Y-F., Peng J. Protective effect of quercetin on pig intestinal integrity after transport stress is associated with regulation oxidative status and inflammation. Journal of Veterinary Medical Science, 2016, 78(9): 1487-1494 CrossRef
  32. Bogolyubova N.V., Nasonova V.V., Nekrasov R.V., Rykov R.A., Semenova A.A., Chabaev M.G. Sposob kormleniya molodnyaka sviney v period otkorma. A.C. (RF) MKI A 23 K 20. A 23 K 50. Federal’noe gosudarstvennoe byudzhetnoe nauchnoe uchrezhdenie «Federal’nyy issledovatel’skiy tsentr zhivotnovodstva — VIZh im. L.K. Еrnsta», Federal’noe gosudarstvennoe byudzhetnoe nauchnoe uchrezhdenie «Federal’nyy nauchnyy tsentr pishchevykh sistem im. V.M. Gorbatova» (RF). Zayavka No. 2022129798/10(065177) ot 17.11.2022 [Method of feeding young pigs during the fattening period. A.C. (RF) MKI A 23 K 20. A 23 K 50. Ernst Federal Research Center for Animal Husbandry VIZh, Gorbatov Federal Scientific Center for Food Systems (RF). Appl. 2022129798/10(065177) dated 11/17/2022](in Russ.).
  33. Kovalenko V.A., Gil’man Z.D., OrlovaA.S. Metodicheskie rekomendatsii po otsenke myasnoy produktivnosti, kachestva myasa i podkozhnogo zhira sviney [Methodological recommendations for assessing meat productivity, meat quality and subcutaneous fat of pigs]. Moscow, 1987 (in Russ.).
  34. Mannapova R.T., Rapiev R.A. Fundamental’nye issledovaniya, 2013, 1: 304-307 (in Russ.).
  35. Peeters E. Neyt A., Beckers F., De Smet S., Aubert A.E., Geers R. Influence of supplemental magnesium, tryptophan, vitamin C, and vitamin E on stress responses of pigs to vibration. Journal of Animal Science, 2005, 83(7): 1568-1580 CrossRef
  36. Bai X., Yan X., Xie L., Hu X., Lin X., Wu C., Zhou N., Wang A., See M.T. Effects of pre-slaughter stressor and feeding preventative Chinese medicinal herbs on glycolysis and oxidative stability in pigs. Animal Science Journal,2015, 87(8): 1028-1033 CrossRef
  37. Singh A.K., Pandita S., Upadhyay R.C., Chandra G., Chaudhari B.K., Maurya P.K. Effect of pre-partum supplementation of vitamin e to murrah buffaloes on metabolic adaptation and growth performance of calves. Indian Journal of Animal Research, 2023, 47(3): 196-204.
  38. Clegg P.C., Clegg A.G. Hormones, cells and Organisms the role of hormones in mammals. Stanford University Press Stanford. California, 1969.
  39. Semenova A.A., Kuznetsova T.G., Nasonova V.V., Nekrasov R.V., Bogolyubova N.V. Myopathy as a destabilizing factor of meat quality formation. Theory and Practice of Meat Processing, 2019, 4(3): 24-31 CrossRef
  40. Mekin R.S., Derkho M.A. Uchenye zapiski Kazanskoy gosudarstvennoy akademii veterinarnoy meditsiny imeni N.Е. Baumana, 2021, 245(1): 101-107 CrossRef (in Russ.).
  41. Pathak P.K., Roychoudhury R., Saharia J., Borah M.C., Dutta D.J., Bhuyan R., Kalita D. Impact of seasonal thermal stress on physiological and blood biochemical parameters in pigs under different dietary energy levels. Trop. Anim. Health Prod., 2018, 50: 1025-1032 CrossRef
  42. Kim Y.-H., Kim K.-Y. Effect of air cleaner on stress hormones of pig and pork quality. J. Anim. Sci. Technol., 2021, 63(4): 892-903 CrossRef
  43. Dang X., Chung Y.H., Kim I.H. Effects of dietary supplementation of herbal active ingredients promoting insulin-like growth factor-1 secretion on production performance, egg quality, blood hematology, and excreta gas emission in laying hens. Animal Bioscience, 2021, 34(11): 1802-1810 CrossRef
  44. Mohana Devi S., Park J., Kim I.H. Effect of plant extracts on growth performance and insulin-like growth factor 1 secretion in growing pigs. Revista Brasileira de Zootecnia, 2015, 44(10): 355-360 CrossRef
  45. Liu G., Wei Y., Wang Z., Wu D., Zhou A., Liu G. Effects of herbal extract supplementation on growth performance and insulin-like growth factor (IGF)-I system in finishing pigs. Journal of Animal and Feed Sciences, 2008, 17(4): 538-547 CrossRef
  46. Gubin D.G. Mezhdunarodnyy zhurnal prikladnykh i fundamental’nykh issledovaniy, 2016, 11(6): 1048-1053 (in Russ.).
  47. Duan T., Wu Z., Zhang, H., Liu Y., Li  Y., Zhang W.  Effects of melatonin implantation on carcass characteristics, meat quality and tissue levels of melatonin and prolactin in Inner Mongolian cashmere goats. J. Animal Sci. Biotechnol., 2019, 10: 70 CrossRef
  48. Tang J., Faustman C., Mancini R.A., Seyfert M., Hunt M.C. The effects of freeze-thaw and sonication on mitochondrial oxygen consumption, electron transport chain-linked metmyoglobin reduction, lipid oxidation, and oxymyoglobin oxidation. Meat Science, 2006, 74(3): 510-515 CrossRef
  49. Todini L. Thyroid hormones in small ruminants: effects of endogenous, environmental and nutritional factors. Animal, 2007, 1(7): 997-1008 CrossRef
  50. Zhang S., Gao H., Yuan X., Wang J., Zang J. Integrative analysis of energy partition patterns and plasma metabolomics profiles of modern growing pigs raised at different ambient temperatures. Animals, 2020, 10(11): 1953 CrossRef
  51. Brent G.A. Tissue-specific actions of thyroid hormone: insights from animal models. Rev. Endocr. Metab. Disord.,2000, 1: 27-33 CrossRef
  52. Hansen P.S., Brix T.H., Sørensen T.I.A., Kyvik K.O., Hegedüs L. Major genetic influence on the regulation of the pituitary-thyroid axis: A study of healthy danish twins. The Journal of Clinical Endocrinology & Metabolism, 2004, 89(3): 1181-1187 CrossRef
  53. Panicker V., Wilson S.G., Spector T.D., Brown S.J., Falchi M., Richards J.B., Surdulescu G.L., Lim E.M., Fletcher S.J., Walsh J.P. Heritability of serum TSH, free T4 and free T3 concentrations: a study of a large UK twin cohort. Clinical Endocrinology,2008, 68(4): 652-659 CrossRef
  54. Chaker L., Korevaar T.I.M., Medici M., Uitterlinden A.G., Hofman A., Dehghan A., Franco O.H., Peeters R.P. Thyroid function characteristics and determinants: The Rotterdam study. Thyroid, 2016, 26(9): 1195-1204 CrossRef
  55. Song Q., Chen X., Su Y., Xie Z., Wang S., Cui B. Age and gender specific thyroid hormones and their relationships with body mass index in a large Chinese population. International Journal of Endocrinology and Metabolism, 2019, 17(1): e66450 CrossRef
  56. Knezevic J., Starchl C., Berisha A.T., Amrein K. Thyroid-gut-axis: How does the microbiota influence thyroid function? Nutrients, 2020, 12(6): 1769 CrossRef
  57. Helmreich D.L., Parfitt D.B., Lu X.-Y., Akil H., Watson S.J. Relation between the hypothalamic-pituitary-thyroid (HPT) axis and the hypothalamic-pituitary-adrenal (HPA) axis during repeated stress. Neuroendocrinology, 2005, 81(3): 183-192 CrossRef
  58. Gore A.C., Chappell V.A., Fenton S.E., Flaws J.A., Nadal A., Prins G.S., Toppari J., Zoeller R.T. EDC-2: The endocrine society’s second scientific statement on endocrine-disrupting chemicals. Endocrine Reviews, 2015, 36(6): E1-E150 CrossRef
  59. Otun J., Sahebkar A., Östlundh L., Atkin S.L., Sathyapalan T. Systematic review and meta-analysis on the effect of soy on thyroid function. Sci. Rep., 2019, 9: 3964 CrossRef
  60. Śmiecińska K., Denaburski J., Sobotka W. Slaughter value, meat quality, creatine kinase activity and cortisol levels in the blood serum of growing-finishing pigs slaughtered immediately after transport and after a rest period. Journal of Veterinary Sciences, 2011, 14(1): 47-54 CrossRef
  61. Terlouw E.M., Picard B., Deiss V., Berri C., Hocquette J.-F., Lebret B., Lefèvre F., Hamill R., Gagaoua M. Understanding the determination of meat quality using biochemical characteristics of the muscle: stress at slaughter and other missing keys. Foods, 2021, 10(1): 84 CrossRef
  62. Yoshioka G., Imaeda N., Ohtani T., Hayashia K. Effects of cortisol on muscle proteolysis and meat quality in piglets. Meat Science, 2005, 71(3): 590-593 CrossRef
  63. Ostrenko K.S., Lemeshevsky V.O., Ovcharova A.N., Galochkina V.P., Sofronova O.V. Effect of adaptogens on the quality of pig meat. Ukrainian Journal of Ecology, 2020, 10(1): 344-348 CrossRef
  64. Govindasamy K., Gonmei C., Singh N.S., Singh N.M. Thermal stress-related physiological, behavioral, and serum biochemical responses in indigenous pigs adapted to Eastern Himalayan region. Front. Vet. Sci., 2022, 9: 1034635 CrossRef
  65. Rosochacki S. J., Piekarzewska A.B., Poloszynowicz J., Sakowski T. The influence of restraint immobilization stress on the concentration of bioamines and cortisol in plasma of Pietrain and Duroc pigs. Journal of Veterinary Medicine Series A, 2007, 47(4): 231-242 CrossRef