Hormonal regulation of prooxidant-antioxidant homeostasis in gilts

The results of research on the features of cyclic lability of homeostasis in gilts are highlighted. In the experiments it has been used gilts of the Red White belted breed of meat pigs at different phases of the reproductive cycle: luteal phase, estrus, on the 15th, 20th, 30th, 60th, 90th, 104th, 113th day of pregnancy and in 12 hours after farrowing. The dynamics of the content of thyroid and steroid hormones, as well as the peculiarities of the formation of prooxidant-antioxidant homeostasis were determined in blood serum. It was found out that the amount of steroid hormones in blood of gilts is labile and is determined by the physiological state, namely the onset of estrus, relative to the luteal phase, it is increased the level of thyroxine (30.0 %), triiodothyronine (26.3 %), estradiol-17 β (by 22.8 %, P < 0.01) testosterone (15.2 %), as well as a decrease in progesterone (by 37.2 %). Such changes are accompanied by the acceleration of peroxidation processes, xanthine oxidase activity increases, it is increased the content of diene conjugates (P < 0.05) and TBA-active compounds. This is accompanied by a probable increase in the level of antioxidant protection – the activity of superoxide dismutase (P < 0.05), vitamin A (P < 0.05) and vitamin E (P < 0.05). During two months of pregnancy, the concentration of thyroxine (P < 0.05), triiodothyronine, progesterone (P < 0.01), testosterone (P < 0.05) and estradiol-17β increases. Such metabolic shifts cause changes in the state of prooxidant-antioxidant homeostasis in the direction of reducing the intensity of peroxidation processes. In gilts before farrow there is a decrease in thyrocoxin, triiodothyronine and progesterone. The intensification of peroxidation was found: the increase in SOD activity (P < 0.05), the dehydroascorbic acid content (P < 0.05), diene conjugates and TBA-active complexes, as well as the decrease in the concentration of reduced glutathione and vitamin A (P < 0.05) and vitamin E (P < 0.05). In blood of sows after farrowing, the concentration of thyroxine increases on 1.3 times, triiodothyronine – on 2.7 times, and progesterone and estradiol-17β decreases on 1.8 and 8.7 times, respectively. It was revealed that the intensity of lipid peroxidation processes decreased: DC content by 16.3 % and TBA-active complexes by 13.3%. It was determined that the concentration of ascorbic acid decreased by 32.8 % and vitamin E – 18.9 %.