[Hormonal disruptors and farm animals].

A number of man made environmental contaminants displays a weak hormonal, usually oestrogenic, activity. Currently such contaminants are termed hormone disruptors, a terminology that also includes natural compounds with hormonal activity, such as phyto and fungal oestrogens. Fertility and morphological defects in wildlife are related to high exposure to man made hormone disruptors. The potential threat of such exposure for human reproductive health is widely discussed. A possible decline in sperm counts in men is one of the subjects related to such environmental factors. There are no firm indications for this threat. Additional research is needed, however, for a more complete assessment. Farm animals so far played a minor role in the discussion. Therefore, in a study published elsewhere, long term trends in sperm counts of Dutch Dairy Bulls have been evaluated (27). No decline was found in 75,238 ejaculates collected between 1977 and 1996 from 2,314 bulls of the centre for artificial insemination (AI) NOORDWEST. Results of this study, published elsewhere, formed the reason to broader go into the relation between hormone disruptors and farm animals, observed effects of phyto-oestrogens in such animal and the role these animals could play in further research.