Brunstbeteendets relation till gyltans intag av genistein

Abstract: Many scientists agree that phytoestrogens could have an effect on the reproduction of an animal. The question is now why and what mechanisms that play an important role. This paper has been focusing on the estrus behavior of gilts by use of a behavioral study. Some of the gilts were given additional feed with the phytoestrogen genistein which commonly occurs in the feed as a part of soybean products. Blood samples were collected and analyzed for progesterone and estradiol concentrations. Due to few samples, possible differences in hormonal levels between feeding groups could not be determined. The results from the behavioral study show a clear difference (P<0.001) in vocalization rate prior to estrus between the two feeding groups. The gilts given feed with no genistein had a higher vocalization rate than those with genistein in the feed. This has not previously been shown for pigs. The results of this study, and possible explanations, are discussed in relation to available literature on the subject.