Search

The effect of 10% dietary flaxseed fed for 3 and 6 weeks on serum hormone levels of fattening gilts, the fatty acid (FA) follicular fluid (FF) composition of small and large antral follicles, and the steroidogenesis and IGF-I secretion by isolated small antral follicles and their response to regulatory hormones (LH, FSH, IGF-I) was studied using immunoassay and gas chromatography analyses. Both supplemental periods increased levels of P4 and IGF-I in blood serum. A shorter period inhibited steroidogenesis (P4, T, E2) and IGF-I secretion by small antral follicles, which was associated with decreased levels of monounsaturated FAs (MUFA) and preferred n-6 polyunsaturated FA (PUFA) metabolism. A longer period stimulated hormone secretion at elevated levels of saturated FAs (SFA) at the expense of MUFAs and PUFAs preferring the n-3 PUFA metabolism. Out of ovarian regulators, only LH and IGF-I were able to alter the secretion of steroids and IGF-I by small follicles of fattening pigs fed a basal diet. The effect of flaxseed on the secretion of follicular hormones after both supplemental periods was altered by all regulatory hormones in a dose-dependent manner. The level of SFAs and PUFAs in FF of large follicles increased with the length of flaxseed feeding, suggesting the suppression of ovulation. [ABSTRACT FROM AUTHOR]

Flaxseed is an important supplement in animal feed. It contains high levels of polyunsaturated fatty acids and lignans acting as phytoestrogens, which can alter cell functions in various organs. The aim of this work was to analyse the effect of supplemental flaxseed in pigs on the morphophysiological properties of the uterus. The experiment included 12 Landras fattening pigs. The control group was fed with a standard feeding mixture for fattening pigs and the experimental group was fed a standard mixture with an addition of 10 % milled flaxseed. After six weeks of fattening, six animals of each group were slaughtered and samples of the uterine horns were taken for the routine histological (height of the endometrium and its compartments, number of endometrial glands, and myometrium height) and for immunohistochemical (expression of oestrogen and progesterone receptor markers) analyses. In the experimental group fed a flaxseed supplement, significant thickening of the superficial epithelium, endometrium, and lamina propria layer was found. The number of endometrial glands was higher than in the control uteri by about 1/3. Moreover, a flaxseed-enriched diet significantly increased the expression of oestrogen receptors a and p, as well as progesterone B receptors in all uterine compartments. The addition of flaxseed in the feed for six weeks had a stimulating effect on the monitored parameters of the uterus of fattening pigs. [ABSTRACT FROM AUTHOR]